diff --git a/backend/migrations/20260424000001_add_pending_payments_polling_index.js b/backend/migrations/20260424000001_add_pending_payments_polling_index.js
new file mode 100644
index 00000000..930c82c0
--- /dev/null
+++ b/backend/migrations/20260424000001_add_pending_payments_polling_index.js
@@ -0,0 +1,20 @@
+/**
+ * Add a partial index for the Ledger Monitor pending-payment scan.
+ *
+ * The poller filters on status + created_at and excludes soft-deleted rows,
+ * so this partial index lets Postgres satisfy that query without scanning the
+ * broader payments indexes.
+ */
+
+export async function up(knex) {
+  await knex.raw(
+    "CREATE INDEX IF NOT EXISTS payments_pending_created_idx ON payments(status, created_at ASC) WHERE deleted_at IS NULL",
+  );
+
+  console.log("✓ Added payments_pending_created_idx for Ledger Monitor polling");
+}
+
+export async function down(knex) {
+  await knex.raw("DROP INDEX IF EXISTS payments_pending_created_idx");
+  console.log("✓ Removed payments_pending_created_idx");
+}
\ No newline at end of file
diff --git a/backend/src/lib/horizon-poller.js b/backend/src/lib/horizon-poller.js
index 9f217e82..0bf29fbb 100644
--- a/backend/src/lib/horizon-poller.js
+++ b/backend/src/lib/horizon-poller.js
@@ -47,6 +47,14 @@ import {
 const POLL_INTERVAL_MS = 15_000;       // 15 seconds between normal cycles
 const BATCH_SIZE = 50;                 // max pending payments per cycle
 const MAX_AGE_HOURS = 24;             // ignore payments older than 24 h (likely abandoned)
+const MERCHANT_NOTIFICATION_FIELDS = [
+  "webhook_secret",
+  "webhook_version",
+  "notification_email",
+  "email",
+  "business_name",
+  "webhook_custom_headers",
+].join(", ");
 
 /** Back-off schedule (ms) applied after consecutive Horizon fetch failures. */
 const BACKOFF_DELAYS_MS = [5_000, 15_000, 30_000, 60_000];
@@ -152,10 +160,11 @@ async function pollPendingPayments() {
 
     const { data: pending, error } = await supabase
       .from("payments")
-      .select("id, amount, asset, asset_issuer, recipient, memo, memo_type, webhook_url, created_at, merchant_id, merchants(webhook_secret, webhook_version, notification_email, email, business_name, webhook_custom_headers)")
+      .select("id, amount, asset, asset_issuer, recipient, memo, memo_type, webhook_url, created_at, merchant_id, metadata")
       .eq("status", "pending")
       .is("deleted_at", null)
       .gte("created_at", cutoff)
+      .order("created_at", { ascending: true })
       .limit(BATCH_SIZE);
 
     if (error) {
@@ -489,7 +498,7 @@ async function checkPayment(payment) {
     }
 
     // Webhook
-    const merchant = payment.merchants;
+    const merchant = await loadMerchantNotificationConfig(payment.merchant_id);
     if (merchant) {
       const webhookPayload = getPayloadForVersion(
         merchant.webhook_version || "v1",
@@ -544,3 +553,25 @@ async function checkPayment(payment) {
 function sleep(ms) {
   return new Promise((resolve) => setTimeout(resolve, ms));
 }
+
+async function loadMerchantNotificationConfig(merchantId) {
+  if (!merchantId) {
+    return null;
+  }
+
+  const { data, error } = await supabase
+    .from("merchants")
+    .select(MERCHANT_NOTIFICATION_FIELDS)
+    .eq("id", merchantId)
+    .maybeSingle();
+
+  if (error) {
+    logger.warn(
+      { err: error, merchantId },
+      "Horizon poller: failed to load merchant notification config",
+    );
+    return null;
+  }
+
+  return data ?? null;
+}
diff --git a/backend/src/lib/horizon-poller.test.js b/backend/src/lib/horizon-poller.test.js
index d7763d61..5c9c8f23 100644
--- a/backend/src/lib/horizon-poller.test.js
+++ b/backend/src/lib/horizon-poller.test.js
@@ -117,14 +117,18 @@ function makePayment(overrides = {}) {
     created_at: new Date(Date.now() - 5_000).toISOString(),
     merchant_id: "merchant-001",
     metadata: {},
-    merchants: {
-      webhook_secret: "secret",
-      webhook_version: "v1",
-      notification_email: "merchant@example.com",
-      email: "merchant@example.com",
-      business_name: "Test Merchant",
-      webhook_custom_headers: {},
-    },
+    ...overrides,
+  };
+}
+
+function makeMerchant(overrides = {}) {
+  return {
+    webhook_secret: "secret",
+    webhook_version: "v1",
+    notification_email: "merchant@example.com",
+    email: "merchant@example.com",
+    business_name: "Test Merchant",
+    webhook_custom_headers: {},
     ...overrides,
   };
 }
@@ -181,9 +185,10 @@ describe("Ledger Monitor — error recovery (Issue #627)", () => {
       const payment = makePayment();
 
       // The poller makes 3 calls to supabase.from("payments"):
-      //   1. Fetch pending payments (select + limit)
+      //   1. Fetch pending payments (select + order + limit)
       //   2. Duplicate-tx guard (select + neq + maybeSingle → null)
       //   3. Atomic update (update + maybeSingle → { id })
+      //   4. Merchant notification config lookup
       let fromCallCount = 0;
       mockSupabaseFrom.mockImplementation(() => {
         fromCallCount += 1;
@@ -194,6 +199,7 @@ describe("Ledger Monitor — error recovery (Issue #627)", () => {
             eq: vi.fn().mockReturnThis(),
             is: vi.fn().mockReturnThis(),
             gte: vi.fn().mockReturnThis(),
+            order: vi.fn().mockReturnThis(),
             limit: vi.fn().mockResolvedValue({ data: [payment], error: null }),
           };
         }
@@ -207,14 +213,21 @@ describe("Ledger Monitor — error recovery (Issue #627)", () => {
             maybeSingle: vi.fn().mockResolvedValue({ data: null, error: null }),
           };
         }
-        // Atomic update — success
+        if (fromCallCount === 3) {
+          // Atomic update — success
+          return {
+            update: vi.fn().mockReturnValue({
+              eq: vi.fn().mockReturnThis(),
+              is: vi.fn().mockReturnThis(),
+              select: vi.fn().mockReturnThis(),
+              maybeSingle: vi.fn().mockResolvedValue({ data: { id: payment.id }, error: null }),
+            }),
+          };
+        }
         return {
-          update: vi.fn().mockReturnValue({
-            eq: vi.fn().mockReturnThis(),
-            is: vi.fn().mockReturnThis(),
-            select: vi.fn().mockReturnThis(),
-            maybeSingle: vi.fn().mockResolvedValue({ data: { id: payment.id }, error: null }),
-          }),
+          select: vi.fn().mockReturnThis(),
+          eq: vi.fn().mockReturnThis(),
+          maybeSingle: vi.fn().mockResolvedValue({ data: makeMerchant(), error: null }),
         };
       });
 
@@ -256,6 +269,7 @@ describe("Ledger Monitor — error recovery (Issue #627)", () => {
         eq: vi.fn().mockReturnThis(),
         is: vi.fn().mockReturnThis(),
         gte: vi.fn().mockReturnThis(),
+        order: vi.fn().mockReturnThis(),
         limit: vi.fn().mockResolvedValue({ data: [payment], error: null }),
       }));
 
@@ -287,6 +301,7 @@ describe("Ledger Monitor — error recovery (Issue #627)", () => {
         eq: vi.fn().mockReturnThis(),
         is: vi.fn().mockReturnThis(),
         gte: vi.fn().mockReturnThis(),
+        order: vi.fn().mockReturnThis(),
         limit: vi.fn().mockResolvedValue({ data: [payment], error: null }),
       }));
 
@@ -314,6 +329,7 @@ describe("Ledger Monitor — error recovery (Issue #627)", () => {
         eq: vi.fn().mockReturnThis(),
         is: vi.fn().mockReturnThis(),
         gte: vi.fn().mockReturnThis(),
+        order: vi.fn().mockReturnThis(),
         limit: vi.fn().mockResolvedValue({ data: [payment], error: null }),
       }));
 
@@ -356,6 +372,7 @@ describe("Ledger Monitor — error recovery (Issue #627)", () => {
         eq: vi.fn().mockReturnThis(),
         is: vi.fn().mockReturnThis(),
         gte: vi.fn().mockReturnThis(),
+        order: vi.fn().mockReturnThis(),
         limit: vi.fn().mockResolvedValue({ data: null, error: { message: "DB down" } }),
       }));
 
@@ -379,6 +396,7 @@ describe("Ledger Monitor — error recovery (Issue #627)", () => {
         eq: vi.fn().mockReturnThis(),
         is: vi.fn().mockReturnThis(),
         gte: vi.fn().mockReturnThis(),
+        order: vi.fn().mockReturnThis(),
         limit: vi.fn().mockImplementation(() => {
           callCount += 1;
           if (callCount === 1) {
@@ -422,6 +440,7 @@ describe("Ledger Monitor — error recovery (Issue #627)", () => {
         eq: vi.fn().mockReturnThis(),
         is: vi.fn().mockReturnThis(),
         gte: vi.fn().mockReturnThis(),
+        order: vi.fn().mockReturnThis(),
         limit: vi.fn().mockResolvedValue({ data: [payment], error: null }),
         update: updateMock,
       }));
@@ -466,6 +485,7 @@ describe("Ledger Monitor — error recovery (Issue #627)", () => {
         eq: vi.fn().mockReturnThis(),
         is: vi.fn().mockReturnThis(),
         gte: vi.fn().mockReturnThis(),
+        order: vi.fn().mockReturnThis(),
         limit: vi.fn().mockResolvedValue({ data: [payment], error: null }),
         update: updateMock,
       }));
@@ -503,6 +523,7 @@ describe("Ledger Monitor — error recovery (Issue #627)", () => {
         eq: vi.fn().mockReturnThis(),
         is: vi.fn().mockReturnThis(),
         gte: vi.fn().mockReturnThis(),
+        order: vi.fn().mockReturnThis(),
         limit: vi.fn().mockResolvedValue({ data: [payment], error: null }),
       }));
 
@@ -519,6 +540,7 @@ describe("Ledger Monitor — error recovery (Issue #627)", () => {
         eq: vi.fn().mockReturnThis(),
         is: vi.fn().mockReturnThis(),
         gte: vi.fn().mockReturnThis(),
+        order: vi.fn().mockReturnThis(),
         limit: vi.fn().mockResolvedValue({ data: [payment], error: null }),
       }));
 
@@ -540,6 +562,7 @@ describe("Ledger Monitor — error recovery (Issue #627)", () => {
         neq: vi.fn().mockReturnThis(),
         is: vi.fn().mockReturnThis(),
         gte: vi.fn().mockReturnThis(),
+        order: vi.fn().mockReturnThis(),
         limit: vi.fn().mockResolvedValue({ data: [payment], error: null }),
         // Duplicate check returns an existing payment
         maybeSingle: vi.fn().mockResolvedValue({ data: { id: "other-pay" }, error: null }),
@@ -574,9 +597,73 @@ describe("Ledger Monitor — error recovery (Issue #627)", () => {
         eq: vi.fn().mockReturnThis(),
         is: vi.fn().mockReturnThis(),
         gte: vi.fn().mockReturnThis(),
+        order: vi.fn().mockReturnThis(),
         limit: vi.fn().mockResolvedValue({ data: [], error: null }),
       }));
 
+  describe("merchant notification lookup", () => {
+    it("continues confirmation when merchant notification config lookup fails", async () => {
+      const payment = makePayment();
+
+      let fromCallCount = 0;
+      mockSupabaseFrom.mockImplementation(() => {
+        fromCallCount += 1;
+        if (fromCallCount === 1) {
+          return {
+            select: vi.fn().mockReturnThis(),
+            eq: vi.fn().mockReturnThis(),
+            is: vi.fn().mockReturnThis(),
+            gte: vi.fn().mockReturnThis(),
+            order: vi.fn().mockReturnThis(),
+            limit: vi.fn().mockResolvedValue({ data: [payment], error: null }),
+          };
+        }
+        if (fromCallCount === 2) {
+          return {
+            select: vi.fn().mockReturnThis(),
+            eq: vi.fn().mockReturnThis(),
+            neq: vi.fn().mockReturnThis(),
+            maybeSingle: vi.fn().mockResolvedValue({ data: null, error: null }),
+          };
+        }
+        if (fromCallCount === 3) {
+          return {
+            update: vi.fn().mockReturnValue({
+              eq: vi.fn().mockReturnThis(),
+              is: vi.fn().mockReturnThis(),
+              select: vi.fn().mockReturnThis(),
+              maybeSingle: vi.fn().mockResolvedValue({ data: { id: payment.id }, error: null }),
+            }),
+          };
+        }
+
+        return {
+          select: vi.fn().mockReturnThis(),
+          eq: vi.fn().mockReturnThis(),
+          maybeSingle: vi.fn().mockResolvedValue({ data: null, error: { message: "merchant lookup failed" } }),
+        };
+      });
+
+      mockFindMatchingPayment.mockResolvedValue({
+        id: "op-1",
+        transaction_hash: "tx-abc",
+        received_amount: "10.0000000",
+      });
+      mockVerifyTransactionSignature.mockResolvedValue({
+        valid: true,
+        reason: "ok",
+        isMultiSig: false,
+        signatureCount: 1,
+        thresholdMet: true,
+      });
+
+      await pollOnce();
+
+      expect(mockPaymentConfirmedCounter.inc).toHaveBeenCalledWith({ asset: payment.asset });
+      expect(mockSendWebhook).not.toHaveBeenCalled();
+    });
+  });
+
       await pollOnce();
 
       expect(mockFindMatchingPayment).not.toHaveBeenCalled();
diff --git a/backend/src/lib/rate-limit.js b/backend/src/lib/rate-limit.js
index cfb7f5c5..fd0ddac0 100644
--- a/backend/src/lib/rate-limit.js
+++ b/backend/src/lib/rate-limit.js
@@ -1,7 +1,10 @@
-import rateLimit from "express-rate-limit";
+import { createHash } from "node:crypto";
+import rateLimit, { ipKeyGenerator } from "express-rate-limit";
 import { RedisStore } from "rate-limit-redis";
 
 export const RATE_LIMIT_REDIS_PREFIX = "rl:";
+export const VERIFY_PAYMENT_RATE_LIMIT_WINDOW_MS = 60 * 1000;
+export const VERIFY_PAYMENT_RATE_LIMIT_MAX = 30;
 
 function setStandardRateLimitHeaders(res, rateLimitState) {
   if (!res || !rateLimitState) {
@@ -34,18 +37,40 @@ export function createRedisRateLimitStore({
   });
 }
 
+export function getVerifyPaymentRateLimitKey(req) {
+  const paymentId =
+    typeof req?.params?.id === "string" && req.params.id.length > 0
+      ? req.params.id
+      : "unknown-payment";
+  const merchantId =
+    typeof req?.merchant?.id === "string" && req.merchant.id.length > 0
+      ? `merchant:${req.merchant.id}`
+      : null;
+  const apiKey =
+    typeof req?.headers?.["x-api-key"] === "string" &&
+    req.headers["x-api-key"].length > 0
+      ? `api:${createHash("sha256").update(req.headers["x-api-key"]).digest("hex")}`
+      : null;
+  const ipKey = ipKeyGenerator(req?.ip ?? req?.socket?.remoteAddress ?? "unknown-ip");
+  const actor = merchantId ?? apiKey ?? `ip:${ipKey}`;
+
+  return `${paymentId}:${actor}`;
+}
+
 export function createVerifyPaymentRateLimit({
   store,
   rateLimitFactory = rateLimit,
 } = {}) {
   return rateLimitFactory({
-    windowMs: 15 * 60 * 1000,
-    max: 10,
+    windowMs: VERIFY_PAYMENT_RATE_LIMIT_WINDOW_MS,
+    max: VERIFY_PAYMENT_RATE_LIMIT_MAX,
     message: {
       error: "Too many verification requests, please try again later.",
     },
     standardHeaders: true,
     legacyHeaders: false,
+    validate: { ip: false },
+    keyGenerator: getVerifyPaymentRateLimitKey,
     requestWasSuccessful: (req, res) => {
       setStandardRateLimitHeaders(res, req.rateLimit);
       return res.statusCode < 400;
diff --git a/backend/src/lib/rate-limit.test.js b/backend/src/lib/rate-limit.test.js
index f3ff7387..62d50f51 100644
--- a/backend/src/lib/rate-limit.test.js
+++ b/backend/src/lib/rate-limit.test.js
@@ -1,8 +1,20 @@
 import { beforeEach, describe, expect, it, vi } from "vitest";
+
+vi.mock("rate-limit-redis", () => ({
+  RedisStore: vi.fn(),
+}));
+
+vi.mock("redis", () => ({
+  createClient: vi.fn(),
+}));
+
 import {
   createRedisRateLimitStore,
   createVerifyPaymentRateLimit,
+  getVerifyPaymentRateLimitKey,
   RATE_LIMIT_REDIS_PREFIX,
+  VERIFY_PAYMENT_RATE_LIMIT_MAX,
+  VERIFY_PAYMENT_RATE_LIMIT_WINDOW_MS,
 } from "./rate-limit.js";
 import {
   connectRedisClient,
@@ -41,17 +53,53 @@ describe("createVerifyPaymentRateLimit", () => {
 
     expect(result).toBe(middleware);
     expect(rateLimitFactory).toHaveBeenCalledWith({
-      windowMs: 15 * 60 * 1000,
-      max: 10,
+      windowMs: VERIFY_PAYMENT_RATE_LIMIT_WINDOW_MS,
+      max: VERIFY_PAYMENT_RATE_LIMIT_MAX,
       message: { error: "Too many verification requests, please try again later." },
       standardHeaders: true,
       legacyHeaders: false,
+      validate: { ip: false },
+      keyGenerator: expect.any(Function),
       requestWasSuccessful: expect.any(Function),
       store,
     });
   });
 });
 
+describe("getVerifyPaymentRateLimitKey", () => {
+  it("keys by payment id and merchant when merchant auth is present", () => {
+    expect(
+      getVerifyPaymentRateLimitKey({
+        params: { id: "payment-123" },
+        merchant: { id: "merchant-789" },
+        headers: {},
+        ip: "127.0.0.1",
+      }),
+    ).toBe("payment-123:merchant:merchant-789");
+  });
+
+  it("hashes api keys instead of storing them in limiter keys", () => {
+    const key = getVerifyPaymentRateLimitKey({
+      params: { id: "payment-123" },
+      headers: { "x-api-key": "secret-api-key" },
+      ip: "127.0.0.1",
+    });
+
+    expect(key).toMatch(/^payment-123:api:[a-f0-9]{64}$/);
+    expect(key).not.toContain("secret-api-key");
+  });
+
+  it("falls back to ip-based keys when no merchant or api key is available", () => {
+    expect(
+      getVerifyPaymentRateLimitKey({
+        params: { id: "payment-123" },
+        headers: {},
+        ip: "203.0.113.10",
+      }),
+    ).toBe("payment-123:ip:203.0.113.10");
+  });
+});
+
 describe("redis client helpers", () => {
   beforeEach(() => {
     resetRedisClientForTests();
diff --git a/backend/src/routes/payments.js b/backend/src/routes/payments.js
index a49eeb0a..58ba743f 100644
--- a/backend/src/routes/payments.js
+++ b/backend/src/routes/payments.js
@@ -2,7 +2,6 @@ import "dotenv/config";
 import { randomUUID } from "node:crypto";
 import { logger } from "../lib/logger.js";
 import express from "express";
-import rateLimit from "express-rate-limit";
 import { paymentService } from "../services/paymentService.js";
 import { validateUuidParam } from "../lib/validate-uuid.js";
 import {
@@ -13,6 +12,7 @@ import {
 } from "../lib/request-schemas.js";
 import { validateRequest } from "../lib/validation.js";
 import { createCreatePaymentRateLimit } from "../lib/create-payment-rate-limit.js";
+import { createVerifyPaymentRateLimit } from "../lib/rate-limit.js";
 import { recaptchaMiddleware } from "../lib/recaptcha.js";
 import { sendWebhook, isEventSubscribed } from "../lib/webhooks.js";
 import { sendReceiptEmail } from "../lib/email.js";
@@ -46,13 +46,7 @@ import {
 
 const createPaymentRateLimit = createCreatePaymentRateLimit();
 
-const defaultVerifyPaymentRateLimit = rateLimit({
-  windowMs: 60 * 1000, // 1 minute window
-  max: 30,             // 30 requests per minute per IP (covers 10s polling)
-  message: { error: "Too many verification requests, please try again later." },
-  standardHeaders: true,
-  legacyHeaders: false,
-});
+const defaultVerifyPaymentRateLimit = createVerifyPaymentRateLimit();
 
 
 
diff --git a/frontend/src/app/(authenticated)/payment-history/page.tsx b/frontend/src/app/(authenticated)/payment-history/page.tsx
index c5ef716c..136f6f47 100644
--- a/frontend/src/app/(authenticated)/payment-history/page.tsx
+++ b/frontend/src/app/(authenticated)/payment-history/page.tsx
@@ -1,6 +1,6 @@
 "use client";
 
-import { useCallback, useEffect, useMemo, useState } from "react";
+import { useCallback, useEffect, useMemo, useReducer, useState } from "react";
 import { usePathname, useRouter, useSearchParams } from "next/navigation";
 import { useLocale, useTranslations } from "next-intl";
 import Skeleton from "react-loading-skeleton";
@@ -15,6 +15,14 @@ import {
   useMerchantApiKey,
   useMerchantId,
 } from "@/lib/merchant-store";
+import {
+  buildPaymentHistorySearchParams,
+  DEFAULT_PAYMENT_HISTORY_FILTERS,
+  filtersFromSearchParams,
+  hasActivePaymentHistoryFilters,
+  type PaymentHistoryFilterKey,
+  paymentHistoryFiltersReducer,
+} from "@/lib/payment-history-filters";
 import { usePaymentSocket } from "@/lib/usePaymentSocket";
 
 interface Payment {
@@ -31,14 +39,6 @@ interface PaginatedResponse {
   total_count: number;
 }
 
-interface FilterState {
-  search: string;
-  status: string;
-  asset: string;
-  dateFrom: string;
-  dateTo: string;
-}
-
 const LIMIT = 50;
 const STATUS_OPTIONS = [
   "all",
@@ -48,40 +48,11 @@ const STATUS_OPTIONS = [
   "refunded",
 ] as const;
 const ASSET_OPTIONS = ["all", "XLM", "USDC"] as const;
-const DEFAULT_FILTERS: FilterState = {
-  search: "",
-  status: "all",
-  asset: "all",
-  dateFrom: "",
-  dateTo: "",
-};
 
 function toStatusLabel(t: ReturnType<typeof useTranslations>, status: string) {
   return t.has(`statuses.${status}`) ? t(`statuses.${status}`) : status;
 }
 
-function filtersFromSearchParams(searchParams: URLSearchParams): FilterState {
-  return {
-    search: searchParams.get("search") ?? "",
-    status: searchParams.get("status") ?? "all",
-    asset: searchParams.get("asset") ?? "all",
-    dateFrom: searchParams.get("date_from") ?? "",
-    dateTo: searchParams.get("date_to") ?? "",
-  };
-}
-
-function buildSearchParams(filters: FilterState): URLSearchParams {
-  const params = new URLSearchParams();
-
-  if (filters.search) params.set("search", filters.search);
-  if (filters.status !== "all") params.set("status", filters.status);
-  if (filters.asset !== "all") params.set("asset", filters.asset);
-  if (filters.dateFrom) params.set("date_from", filters.dateFrom);
-  if (filters.dateTo) params.set("date_to", filters.dateTo);
-
-  return params;
-}
-
 export default function PaymentHistoryPage() {
   const t = useTranslations("recentPayments");
   const locale = localeToLanguageTag(useLocale());
@@ -93,16 +64,15 @@ export default function PaymentHistoryPage() {
 
   useHydrateMerchantStore();
 
-  const filters = useMemo(
+  const activeFilters = useMemo(
     () => filtersFromSearchParams(searchParams),
     [searchParams],
   );
-  const hasActiveFilters =
-    filters.search ||
-    filters.status !== "all" ||
-    filters.asset !== "all" ||
-    filters.dateFrom ||
-    filters.dateTo;
+  const [draftFilters, dispatchDraftFilters] = useReducer(
+    paymentHistoryFiltersReducer,
+    activeFilters,
+  );
+  const hasActiveFilters = hasActivePaymentHistoryFilters(activeFilters);
 
   const [payments, setPayments] = useState<Payment[]>([]);
   const [loading, setLoading] = useState(true);
@@ -115,6 +85,10 @@ export default function PaymentHistoryPage() {
   const [isSheetOpen, setIsSheetOpen] = useState(false);
   const [flashedIds, setFlashedIds] = useState<Set<string>>(new Set());
 
+  useEffect(() => {
+    dispatchDraftFilters({ type: "sync", filters: activeFilters });
+  }, [activeFilters]);
+
   useEffect(() => {
     const handleKeyDown = (e: KeyboardEvent) => {
       // Check for Cmd+C (Mac) or Ctrl+C (Windows/Linux)
@@ -135,8 +109,8 @@ export default function PaymentHistoryPage() {
   }, [hoveredPayment, t]);
 
   const updateFilters = useCallback(
-    (nextFilters: FilterState) => {
-      const params = buildSearchParams(nextFilters);
+    (nextFilters: typeof activeFilters) => {
+      const params = buildPaymentHistorySearchParams(nextFilters);
       const query = params.toString();
       router.replace(query ? `${pathname}?${query}` : pathname, {
         scroll: false,
@@ -145,25 +119,47 @@ export default function PaymentHistoryPage() {
     [pathname, router],
   );
 
+  useEffect(() => {
+    const timer = window.setTimeout(() => {
+      if (draftFilters.search !== activeFilters.search) {
+        updateFilters({ ...draftFilters });
+      }
+    }, 300);
+
+    return () => window.clearTimeout(timer);
+  }, [activeFilters.search, draftFilters, updateFilters]);
+
   const handleFilterChange = useCallback(
-    (key: keyof FilterState, value: string) => {
-      updateFilters({ ...filters, [key]: value });
+    (key: PaymentHistoryFilterKey, value: string) => {
+      const nextFilters = paymentHistoryFiltersReducer(draftFilters, {
+        type: "set",
+        key,
+        value,
+      });
+      dispatchDraftFilters({ type: "set", key, value });
+
+      if (key !== "search") {
+        updateFilters(nextFilters);
+      }
     },
-    [filters, updateFilters],
+    [draftFilters, updateFilters],
   );
 
   const clearFilter = useCallback(
-    (key: keyof FilterState) => {
-      updateFilters({
-        ...filters,
-        [key]: key === "status" || key === "asset" ? "all" : "",
+    (key: PaymentHistoryFilterKey) => {
+      const nextFilters = paymentHistoryFiltersReducer(draftFilters, {
+        type: "clear",
+        key,
       });
+      dispatchDraftFilters({ type: "clear", key });
+      updateFilters(nextFilters);
     },
-    [filters, updateFilters],
+    [draftFilters, updateFilters],
   );
 
   const clearAllFilters = useCallback(() => {
-    updateFilters(DEFAULT_FILTERS);
+    dispatchDraftFilters({ type: "reset" });
+    updateFilters(DEFAULT_PAYMENT_HISTORY_FILTERS);
   }, [updateFilters]);
 
   const handleConfirmed = useCallback(
@@ -215,7 +211,7 @@ export default function PaymentHistoryPage() {
 
         const apiUrl =
           process.env.NEXT_PUBLIC_API_URL || "http://localhost:4000";
-        const params = buildSearchParams(filters);
+        const params = buildPaymentHistorySearchParams(activeFilters);
         params.set("page", page.toString());
         params.set("limit", LIMIT.toString());
 
@@ -249,7 +245,7 @@ export default function PaymentHistoryPage() {
     fetchPayments();
 
     return () => controller.abort();
-  }, [apiKey, filters, t]);
+  }, [activeFilters, apiKey, t]);
 
   const handlePaymentClick = (paymentId: string) => {
     setSelectedPayment(paymentId);
@@ -604,7 +600,7 @@ export default function PaymentHistoryPage() {
               <input
                 id="search"
                 type="text"
-                value={filters.search}
+                value={draftFilters.search}
                 onChange={(event) =>
                   handleFilterChange("search", event.target.value)
                 }
@@ -637,7 +633,7 @@ export default function PaymentHistoryPage() {
               </label>
               <select
                 id="status"
-                value={filters.status}
+                value={draftFilters.status}
                 onChange={(event) =>
                   handleFilterChange("status", event.target.value)
                 }
@@ -662,7 +658,7 @@ export default function PaymentHistoryPage() {
               </label>
               <select
                 id="asset"
-                value={filters.asset}
+                value={draftFilters.asset}
                 onChange={(event) =>
                   handleFilterChange("asset", event.target.value)
                 }
@@ -686,7 +682,7 @@ export default function PaymentHistoryPage() {
               <input
                 id="dateFrom"
                 type="date"
-                value={filters.dateFrom}
+                value={draftFilters.dateFrom}
                 onChange={(event) =>
                   handleFilterChange("dateFrom", event.target.value)
                 }
@@ -704,7 +700,7 @@ export default function PaymentHistoryPage() {
               <input
                 id="dateTo"
                 type="date"
-                value={filters.dateTo}
+                value={draftFilters.dateTo}
                 onChange={(event) =>
                   handleFilterChange("dateTo", event.target.value)
                 }
@@ -717,9 +713,9 @@ export default function PaymentHistoryPage() {
             <div className="flex flex-wrap items-center gap-2 pt-2">
               <span className="text-xs text-[#6B6B6B]">Active filters:</span>
 
-              {filters.search && (
+              {activeFilters.search && (
                 <span className="inline-flex items-center gap-1 rounded-full border border-mint/30 bg-mint/10 px-3 py-1 text-xs text-mint">
-                  Search: &quot;{filters.search}&quot;
+                  Search: &quot;{activeFilters.search}&quot;
                   <button
                     onClick={() => clearFilter("search")}
                     className="ml-1 rounded-full p-0.5 hover:bg-mint/20"
@@ -741,9 +737,9 @@ export default function PaymentHistoryPage() {
                   </button>
                 </span>
               )}
-              {filters.status !== "all" && (
+              {activeFilters.status !== "all" && (
                 <span className="inline-flex items-center gap-1 rounded-full border border-mint/30 bg-mint/10 px-3 py-1 text-xs text-mint">
-                  Status: {filters.status}
+                  Status: {activeFilters.status}
                   <button
                     onClick={() => clearFilter("status")}
                     className="ml-1 rounded-full p-0.5 hover:bg-mint/20"
@@ -765,9 +761,9 @@ export default function PaymentHistoryPage() {
                   </button>
                 </span>
               )}
-              {filters.asset !== "all" && (
+              {activeFilters.asset !== "all" && (
                 <span className="inline-flex items-center gap-1 rounded-full border border-mint/30 bg-mint/10 px-3 py-1 text-xs text-mint">
-                  Asset: {filters.asset}
+                  Asset: {activeFilters.asset}
                   <button
                     onClick={() => clearFilter("asset")}
                     className="ml-1 rounded-full p-0.5 hover:bg-mint/20"
@@ -789,9 +785,9 @@ export default function PaymentHistoryPage() {
                   </button>
                 </span>
               )}
-              {filters.dateFrom && (
+              {activeFilters.dateFrom && (
                 <span className="inline-flex items-center gap-1 rounded-full border border-mint/30 bg-mint/10 px-3 py-1 text-xs text-mint">
-                  From: {filters.dateFrom}
+                  From: {activeFilters.dateFrom}
                   <button
                     onClick={() => clearFilter("dateFrom")}
                     className="ml-1 rounded-full p-0.5 hover:bg-mint/20"
@@ -813,9 +809,9 @@ export default function PaymentHistoryPage() {
                   </button>
                 </span>
               )}
-              {filters.dateTo && (
+              {activeFilters.dateTo && (
                 <span className="inline-flex items-center gap-1 rounded-full border border-mint/30 bg-mint/10 px-3 py-1 text-xs text-mint">
-                  To: {filters.dateTo}
+                  To: {activeFilters.dateTo}
                   <button
                     onClick={() => clearFilter("dateTo")}
                     className="ml-1 rounded-full p-0.5 hover:bg-mint/20"
diff --git a/frontend/src/components/PaymentMetrics.test.tsx b/frontend/src/components/PaymentMetrics.test.tsx
index 8b3cdb18..f35bea14 100644
--- a/frontend/src/components/PaymentMetrics.test.tsx
+++ b/frontend/src/components/PaymentMetrics.test.tsx
@@ -19,7 +19,7 @@ vi.mock("@/lib/merchant-store", () => ({
     useHydrateMerchantStore: vi.fn(),
 }));
 
-global.ResizeObserver = vi.fn().mockImplementation(() => ({
+globalThis.ResizeObserver = vi.fn().mockImplementation(() => ({
     observe: vi.fn(),
     unobserve: vi.fn(),
     disconnect: vi.fn(),
@@ -39,12 +39,12 @@ vi.mock("recharts", () => ({
 describe("PaymentMetrics Component", () => {
     beforeEach(() => {
         vi.resetAllMocks();
-        global.fetch = vi.fn();
+        globalThis.fetch = vi.fn();
     });
 
     it("renders loading skeleton initially", () => {
         // Fetch never resolves — component stays in loading state
-        (global.fetch as any).mockReturnValue(new Promise(() => {}));
+        (globalThis.fetch as any).mockReturnValue(new Promise(() => {}));
 
         render(React.createElement(PaymentMetrics));
 
@@ -60,7 +60,7 @@ describe("PaymentMetrics Component", () => {
             data: [],
         };
 
-        (global.fetch as any)
+        (globalThis.fetch as any)
             .mockResolvedValueOnce({ ok: true, json: async () => mockSummary })
             .mockResolvedValueOnce({ ok: true, json: async () => ({ assets: [], data: [] }) });
 
@@ -73,9 +73,35 @@ describe("PaymentMetrics Component", () => {
         });
     });
 
+    it("exposes an accessible chart region and hidden data table", async () => {
+        (globalThis.fetch as any)
+            .mockResolvedValueOnce({ ok: true, json: async () => ({ total_volume: 1500, confirmed_count: 42, success_rate: 98.5, data: [] }) })
+            .mockResolvedValueOnce({
+                ok: true,
+                json: async () => ({
+                    assets: ["XLM", "USDC"],
+                    data: [
+                        { date: "2026-04-20", count: 2, XLM: 10, USDC: 5 },
+                        { date: "2026-04-21", count: 1, XLM: 12, USDC: 0 },
+                    ],
+                }),
+            });
+
+        render(React.createElement(PaymentMetrics));
+
+        await waitFor(() => {
+            expect(screen.getByRole("region", { name: "chartTitle" })).toBeInTheDocument();
+        });
+
+        expect(screen.getByText(/Range 7D\. Showing 2 of 2 assets across 2 time periods\./)).toBeInTheDocument();
+        expect(screen.getByRole("table", { name: "chartTitle data table" })).toBeInTheDocument();
+        expect(screen.getByRole("columnheader", { name: "XLM" })).toBeInTheDocument();
+        expect(screen.getByRole("cell", { name: "10" })).toBeInTheDocument();
+    });
+
     it("renders error message on fetch failure", async () => {
         // Reject with non-Error so component uses t("fetchMetricsFailed") fallback
-        (global.fetch as any).mockRejectedValue("network failure");
+        (globalThis.fetch as any).mockRejectedValue("network failure");
 
         render(React.createElement(PaymentMetrics));
 
@@ -86,7 +112,7 @@ describe("PaymentMetrics Component", () => {
     });
 
     it("displays 'No payments' message when assets list is empty", async () => {
-        (global.fetch as any)
+        (globalThis.fetch as any)
             .mockResolvedValueOnce({ ok: true, json: async () => ({ total_volume: 0, confirmed_count: 0, success_rate: 0, data: [] }) })
             .mockResolvedValueOnce({ ok: true, json: async () => ({ assets: [], data: [] }) });
 
diff --git a/frontend/src/components/PaymentMetrics.tsx b/frontend/src/components/PaymentMetrics.tsx
index 3d89a288..ccdb2cd6 100644
--- a/frontend/src/components/PaymentMetrics.tsx
+++ b/frontend/src/components/PaymentMetrics.tsx
@@ -1,6 +1,6 @@
 "use client";
 
-import { useEffect, useRef, useState } from "react";
+import { useEffect, useId, useRef, useState } from "react";
 import { useLocale, useTranslations } from "next-intl";
 import * as Recharts from "recharts";
 const {
@@ -83,9 +83,9 @@ function computeMovingAverages(
 
 export default function PaymentMetrics({
   showSkeleton = false,
-}: {
+}: Readonly<{
   showSkeleton?: boolean;
-}) {
+}>) {
   const t = useTranslations("paymentMetrics");
   const locale = localeToLanguageTag(useLocale());
   const [summary, setSummary] = useState<MetricsResponse | null>(null);
@@ -97,6 +97,10 @@ export default function PaymentMetrics({
   const apiKey = useMerchantApiKey();
   const hydrated = useMerchantHydrated();
   const chartContainerRef = useRef<HTMLDivElement>(null);
+  const chartTitleId = useId();
+  const chartDescriptionId = useId();
+  const chartSummaryId = useId();
+  const chartTableId = useId();
 
   useHydrateMerchantStore();
 
@@ -222,6 +226,11 @@ export default function PaymentMetrics({
               : Number(dataPoint.count) || 0,
         }))
       : [];
+  const visibleAssets = assets.filter((asset) => !hiddenAssets.has(asset));
+  const chartSummary =
+    assets.length === 0
+      ? `${t("chartTitle")}. ${t("noPayments")}.`
+      : `${t("chartTitle")}. ${t("chartSubtitle")}. Range ${range}. Showing ${visibleAssets.length} of ${assets.length} assets across ${chartData.length} time periods.`;
 
   return (
     <div className="flex flex-col gap-6">
@@ -272,16 +281,27 @@ export default function PaymentMetrics({
         </div>
       )}
 
-      <div
+      <section
         ref={chartContainerRef}
+        aria-labelledby={chartTitleId}
+        aria-describedby={`${chartDescriptionId} ${chartSummaryId} ${chartTableId}`}
         className="flex flex-col gap-8 rounded-lg border border-[#E8E8E8] bg-white p-8"
       >
+        <div id={chartSummaryId} className="sr-only" aria-live="polite">
+          {chartSummary}
+        </div>
         <div className="flex flex-wrap items-start justify-between gap-3">
           <div>
-            <h3 className="text-sm font-bold text-[#0A0A0A] uppercase tracking-wider">
+            <h3
+              id={chartTitleId}
+              className="text-sm font-bold text-[#0A0A0A] uppercase tracking-wider"
+            >
               {t("chartTitle")}
             </h3>
-            <p className="text-[10px] font-medium text-[#6B6B6B] uppercase tracking-widest mt-1">
+            <p
+              id={chartDescriptionId}
+              className="text-[10px] font-medium text-[#6B6B6B] uppercase tracking-widest mt-1"
+            >
               {t("chartSubtitle")}
             </p>
           </div>
@@ -310,7 +330,6 @@ export default function PaymentMetrics({
         {assets.length > 0 && (
           <div
             className="flex flex-wrap gap-2"
-            role="group"
             aria-label={t("toggleAssetVisibility")}
           >
             {assets.map((asset, index) => {
@@ -354,7 +373,34 @@ export default function PaymentMetrics({
             {t("noPayments")}
           </p>
         ) : (
-          <div data-export-chart>
+          <>
+            <table id={chartTableId} className="sr-only">
+              <caption>{`${t("chartTitle")} data table`}</caption>
+              <thead>
+                <tr>
+                  <th scope="col">Date</th>
+                  {visibleAssets.map((asset) => (
+                    <th key={asset} scope="col">{asset}</th>
+                  ))}
+                </tr>
+              </thead>
+              <tbody>
+                {chartData.map((dataPoint) => (
+                  <tr key={dataPoint.date}>
+                    <th scope="row">{dataPoint.dateShort}</th>
+                    {visibleAssets.map((asset) => (
+                      <td key={`${dataPoint.date}-${asset}`}>
+                        {typeof dataPoint[asset] === "number"
+                          ? dataPoint[asset].toLocaleString()
+                          : Number(dataPoint[asset] || 0).toLocaleString()}
+                      </td>
+                    ))}
+                  </tr>
+                ))}
+              </tbody>
+            </table>
+
+            <div data-export-chart aria-hidden="true">
             <ResponsiveContainer width="100%" height={CHART_HEIGHT}>
               <LineChart
                 data={chartData}
@@ -446,9 +492,10 @@ export default function PaymentMetrics({
                 )}
               </LineChart>
             </ResponsiveContainer>
-          </div>
+            </div>
+          </>
         )}
-      </div>
+      </section>
     </div>
   );
 }
diff --git a/frontend/src/lib/payment-history-filters.test.ts b/frontend/src/lib/payment-history-filters.test.ts
new file mode 100644
index 00000000..9ed2bb6d
--- /dev/null
+++ b/frontend/src/lib/payment-history-filters.test.ts
@@ -0,0 +1,103 @@
+import { describe, expect, it } from "vitest";
+import {
+  buildPaymentHistorySearchParams,
+  DEFAULT_PAYMENT_HISTORY_FILTERS,
+  filtersFromSearchParams,
+  hasActivePaymentHistoryFilters,
+  paymentHistoryFiltersReducer,
+} from "./payment-history-filters";
+
+describe("paymentHistoryFiltersReducer", () => {
+  it("updates a single filter field", () => {
+    expect(
+      paymentHistoryFiltersReducer(DEFAULT_PAYMENT_HISTORY_FILTERS, {
+        type: "set",
+        key: "status",
+        value: "confirmed",
+      }),
+    ).toEqual({
+      ...DEFAULT_PAYMENT_HISTORY_FILTERS,
+      status: "confirmed",
+    });
+  });
+
+  it("clears enum filters back to all", () => {
+    expect(
+      paymentHistoryFiltersReducer(
+        { ...DEFAULT_PAYMENT_HISTORY_FILTERS, asset: "USDC" },
+        {
+          type: "clear",
+          key: "asset",
+        },
+      ),
+    ).toEqual(DEFAULT_PAYMENT_HISTORY_FILTERS);
+  });
+
+  it("resets all filters", () => {
+    expect(
+      paymentHistoryFiltersReducer(
+        {
+          search: "memo",
+          status: "pending",
+          asset: "XLM",
+          dateFrom: "2026-04-01",
+          dateTo: "2026-04-24",
+        },
+        { type: "reset" },
+      ),
+    ).toEqual(DEFAULT_PAYMENT_HISTORY_FILTERS);
+  });
+});
+
+describe("filtersFromSearchParams", () => {
+  it("parses search params into filter state", () => {
+    const searchParams = new URLSearchParams(
+      "search=invoice&status=confirmed&asset=USDC&date_from=2026-04-01&date_to=2026-04-24",
+    );
+
+    expect(filtersFromSearchParams(searchParams)).toEqual({
+      search: "invoice",
+      status: "confirmed",
+      asset: "USDC",
+      dateFrom: "2026-04-01",
+      dateTo: "2026-04-24",
+    });
+  });
+});
+
+describe("buildPaymentHistorySearchParams", () => {
+  it("omits default filters from the URL", () => {
+    expect(
+      buildPaymentHistorySearchParams(DEFAULT_PAYMENT_HISTORY_FILTERS).toString(),
+    ).toBe("");
+  });
+
+  it("serializes active filters", () => {
+    expect(
+      buildPaymentHistorySearchParams({
+        search: "invoice",
+        status: "confirmed",
+        asset: "USDC",
+        dateFrom: "2026-04-01",
+        dateTo: "2026-04-24",
+      }).toString(),
+    ).toBe(
+      "search=invoice&status=confirmed&asset=USDC&date_from=2026-04-01&date_to=2026-04-24",
+    );
+  });
+});
+
+describe("hasActivePaymentHistoryFilters", () => {
+  it("returns false for default filters", () => {
+    expect(hasActivePaymentHistoryFilters(DEFAULT_PAYMENT_HISTORY_FILTERS)).toBe(false);
+  });
+
+  it("returns true when any filter is active", () => {
+    expect(
+      hasActivePaymentHistoryFilters({
+        ...DEFAULT_PAYMENT_HISTORY_FILTERS,
+        search: "invoice",
+      }),
+    ).toBe(true);
+  });
+});
\ No newline at end of file
diff --git a/frontend/src/lib/payment-history-filters.ts b/frontend/src/lib/payment-history-filters.ts
new file mode 100644
index 00000000..27a689dc
--- /dev/null
+++ b/frontend/src/lib/payment-history-filters.ts
@@ -0,0 +1,89 @@
+export interface PaymentHistoryFilterState {
+  search: string;
+  status: string;
+  asset: string;
+  dateFrom: string;
+  dateTo: string;
+}
+
+export type PaymentHistoryFilterKey = keyof PaymentHistoryFilterState;
+
+export type PaymentHistoryFilterAction =
+  | { type: "sync"; filters: PaymentHistoryFilterState }
+  | {
+      type: "set";
+      key: PaymentHistoryFilterKey;
+      value: PaymentHistoryFilterState[PaymentHistoryFilterKey];
+    }
+  | { type: "clear"; key: PaymentHistoryFilterKey }
+  | { type: "reset" };
+
+export const DEFAULT_PAYMENT_HISTORY_FILTERS: PaymentHistoryFilterState = {
+  search: "",
+  status: "all",
+  asset: "all",
+  dateFrom: "",
+  dateTo: "",
+};
+
+export function paymentHistoryFiltersReducer(
+  state: PaymentHistoryFilterState,
+  action: PaymentHistoryFilterAction,
+): PaymentHistoryFilterState {
+  switch (action.type) {
+    case "sync":
+      return action.filters;
+    case "set":
+      return {
+        ...state,
+        [action.key]: action.value,
+      };
+    case "clear":
+      return {
+        ...state,
+        [action.key]: action.key === "status" || action.key === "asset" ? "all" : "",
+      };
+    case "reset":
+      return DEFAULT_PAYMENT_HISTORY_FILTERS;
+    default:
+      return state;
+  }
+}
+
+export function filtersFromSearchParams(
+  searchParams: Pick<URLSearchParams, "get">,
+): PaymentHistoryFilterState {
+  return {
+    search: searchParams.get("search") ?? "",
+    status: searchParams.get("status") ?? "all",
+    asset: searchParams.get("asset") ?? "all",
+    dateFrom: searchParams.get("date_from") ?? "",
+    dateTo: searchParams.get("date_to") ?? "",
+  };
+}
+
+export function buildPaymentHistorySearchParams(
+  filters: PaymentHistoryFilterState,
+): URLSearchParams {
+  const params = new URLSearchParams();
+
+  if (filters.search) params.set("search", filters.search);
+  if (filters.status !== "all") params.set("status", filters.status);
+  if (filters.asset !== "all") params.set("asset", filters.asset);
+  if (filters.dateFrom) params.set("date_from", filters.dateFrom);
+  if (filters.dateTo) params.set("date_to", filters.dateTo);
+
+  return params;
+}
+
+export function hasActivePaymentHistoryFilters(
+  filters: PaymentHistoryFilterState,
+): boolean {
+  return Boolean(
+    filters.search ||
+      filters.status !== "all" ||
+      filters.asset !== "all" ||
+      filters.dateFrom ||
+      filters.dateTo,
+  );
+}