diff --git a/workers/index.ts b/workers/index.ts
index fd3359ce..23cff0e3 100644
--- a/workers/index.ts
+++ b/workers/index.ts
@@ -329,6 +329,25 @@ app.get("/api/v1/mailboxes/:mailboxId/emails/:emailId/attachments/:attachmentId"
 
 const MAX_EMAIL_SIZE = 25 * 1024 * 1024;
 
+type IncomingEmailMessage = {
+	raw: ReadableStream;
+	rawSize: number;
+	to?: string;
+};
+
+function normalizeAddress(address: string | null | undefined) {
+	const normalized = address?.trim().toLowerCase();
+	return normalized || undefined;
+}
+
+function parsedAddressList(
+	addresses: Array<{ address?: string | null }> | undefined,
+) {
+	return (addresses
+		?.map((entry) => normalizeAddress(entry.address))
+		.filter((address): address is string => Boolean(address))) ?? [];
+}
+
 async function streamToArrayBuffer(stream: ReadableStream, streamSize: number) {
 	if (streamSize > MAX_EMAIL_SIZE) throw new Error(`Email too large: ${streamSize} bytes exceeds ${MAX_EMAIL_SIZE} byte limit`);
 	if (streamSize <= 0) throw new Error(`Invalid stream size: ${streamSize}`);
@@ -345,22 +364,29 @@ async function streamToArrayBuffer(stream: ReadableStream, streamSize: number) {
 	return result;
 }
 
-async function receiveEmail(event: { raw: ReadableStream; rawSize: number }, env: Env, ctx: ExecutionContext) {
+async function receiveEmail(event: IncomingEmailMessage, env: Env, ctx: ExecutionContext) {
 	const rawEmail = await streamToArrayBuffer(event.raw, event.rawSize);
 	const parsedEmail = await new PostalMime().parse(rawEmail);
 
-	if (!parsedEmail.to?.length || !parsedEmail.to[0].address) throw new Error("received email with empty to");
+	const envelopeRecipient = normalizeAddress(event.to);
+	const allRecipients = parsedAddressList(parsedEmail.to);
+	if (!envelopeRecipient && allRecipients.length === 0) throw new Error("received email with empty to");
 
-	const allowedAddresses = ((env.EMAIL_ADDRESSES ?? []) as string[]).map((a) => a.toLowerCase());
-	const allRecipients = parsedEmail.to.map((t) => t.address?.toLowerCase()).filter(Boolean) as string[];
-	const ccRecipients = (parsedEmail.cc || []).map((e) => e.address?.toLowerCase()).filter(Boolean) as string[];
-	const bccRecipients = (parsedEmail.bcc || []).map((e) => e.address?.toLowerCase()).filter(Boolean) as string[];
+	const allowedAddresses = ((env.EMAIL_ADDRESSES ?? []) as string[])
+		.map((a) => normalizeAddress(a))
+		.filter(Boolean) as string[];
+	const ccRecipients = parsedAddressList(parsedEmail.cc);
+	const bccRecipients = parsedAddressList(parsedEmail.bcc);
 
 	let mailboxId: string | undefined;
 	if (allowedAddresses.length > 0) {
-		mailboxId = allRecipients.find((addr) => allowedAddresses.includes(addr));
-		if (!mailboxId) { console.log(`Ignoring email: no recipient matches EMAIL_ADDRESSES.`); return; }
-	} else { mailboxId = allRecipients[0]; }
+		const routingRecipients = envelopeRecipient ? [envelopeRecipient] : allRecipients;
+		mailboxId = routingRecipients.find((addr) => allowedAddresses.includes(addr));
+		if (!mailboxId) {
+			console.log(`Ignoring email for ${envelopeRecipient ?? allRecipients.join(", ")}: recipient is not configured in EMAIL_ADDRESSES.`);
+			return;
+		}
+	} else { mailboxId = envelopeRecipient ?? allRecipients[0]; }
 	if (!mailboxId) throw new Error("received email with no valid recipient address");
 
 	const messageId = crypto.randomUUID();
@@ -394,7 +420,7 @@ async function receiveEmail(event: { raw: ReadableStream; rawSize: number }, env
 
 	await stub.createEmail(Folders.INBOX, {
 		id: messageId, subject: parsedEmail.subject || "",
-		sender: (parsedEmail.from?.address || "").toLowerCase(), recipient: allRecipients.join(", "),
+		sender: (parsedEmail.from?.address || "").toLowerCase(), recipient: (allRecipients.length > 0 ? allRecipients : [mailboxId]).join(", "),
 		cc: ccRecipients.join(", ") || null, bcc: bccRecipients.join(", ") || null,
 		date: new Date().toISOString(), // uses receive time, not the email's Date header
 		body: parsedEmail.html || parsedEmail.text || "",