diff --git a/dd-java-agent/instrumentation/spring/spring-webmvc/spring-webmvc-3.1/src/test/groovy/test/boot/SpringBootBasedTest.groovy b/dd-java-agent/instrumentation/spring/spring-webmvc/spring-webmvc-3.1/src/test/groovy/test/boot/SpringBootBasedTest.groovy
index 18badff3e97..89b0389c3da 100644
--- a/dd-java-agent/instrumentation/spring/spring-webmvc/spring-webmvc-3.1/src/test/groovy/test/boot/SpringBootBasedTest.groovy
+++ b/dd-java-agent/instrumentation/spring/spring-webmvc/spring-webmvc-3.1/src/test/groovy/test/boot/SpringBootBasedTest.groovy
@@ -570,6 +570,9 @@ class SpringBootBasedTest extends HttpServerTest<ConfigurableApplicationContext>
             "$Tags.HTTP_ROUTE" "/success"
             "servlet.context" "/boot-context"
             "servlet.path" "/success"
+            if ({ isDataStreamsEnabled() }) {
+              "$DDTags.PATHWAY_HASH" { String }
+            }
             defaultTags()
           }
         }
diff --git a/dd-trace-core/src/main/java/datadog/trace/core/datastreams/DefaultDataStreamsMonitoring.java b/dd-trace-core/src/main/java/datadog/trace/core/datastreams/DefaultDataStreamsMonitoring.java
index 4cbc02acd37..b6487c2c99d 100644
--- a/dd-trace-core/src/main/java/datadog/trace/core/datastreams/DefaultDataStreamsMonitoring.java
+++ b/dd-trace-core/src/main/java/datadog/trace/core/datastreams/DefaultDataStreamsMonitoring.java
@@ -1,6 +1,7 @@
 package datadog.trace.core.datastreams;
 
 import static datadog.communication.ddagent.DDAgentFeaturesDiscovery.V01_DATASTREAMS_ENDPOINT;
+import static datadog.trace.api.DDTags.PATHWAY_HASH;
 import static datadog.trace.api.datastreams.DataStreamsContext.fromTags;
 import static datadog.trace.api.datastreams.DataStreamsTags.Direction.INBOUND;
 import static datadog.trace.api.datastreams.DataStreamsTags.Direction.OUTBOUND;
@@ -309,6 +310,10 @@ public void setCheckpoint(AgentSpan span, DataStreamsContext context) {
     PathwayContext pathwayContext = span.spanContext().getPathwayContext();
     if (pathwayContext != null) {
       pathwayContext.setCheckpoint(context, this::add);
+      long pathwayHash = pathwayContext.getHash();
+      if (pathwayHash != 0) {
+        span.setTag(PATHWAY_HASH, Long.toUnsignedString(pathwayHash));
+      }
     }
   }
 
diff --git a/dd-trace-core/src/test/java/datadog/trace/core/datastreams/DefaultDataStreamsMonitoringTest.java b/dd-trace-core/src/test/java/datadog/trace/core/datastreams/DefaultDataStreamsMonitoringTest.java
index c1c29026c49..6648e1a8c36 100644
--- a/dd-trace-core/src/test/java/datadog/trace/core/datastreams/DefaultDataStreamsMonitoringTest.java
+++ b/dd-trace-core/src/test/java/datadog/trace/core/datastreams/DefaultDataStreamsMonitoringTest.java
@@ -10,8 +10,10 @@
 import static org.junit.jupiter.api.Assertions.assertNotNull;
 import static org.junit.jupiter.api.Assertions.assertTrue;
 import static org.mockito.ArgumentMatchers.any;
+import static org.mockito.ArgumentMatchers.eq;
 import static org.mockito.Mockito.RETURNS_SMART_NULLS;
 import static org.mockito.Mockito.mock;
+import static org.mockito.Mockito.never;
 import static org.mockito.Mockito.verify;
 import static org.mockito.Mockito.when;
 
@@ -19,13 +21,18 @@
 import datadog.metrics.api.Histograms;
 import datadog.metrics.impl.DDSketchHistograms;
 import datadog.trace.api.Config;
+import datadog.trace.api.DDTags;
 import datadog.trace.api.TraceConfig;
+import datadog.trace.api.datastreams.DataStreamsContext;
 import datadog.trace.api.datastreams.DataStreamsTags;
 import datadog.trace.api.datastreams.KafkaConfigReport;
+import datadog.trace.api.datastreams.PathwayContext;
 import datadog.trace.api.datastreams.SchemaRegistryUsage;
 import datadog.trace.api.datastreams.StatsPoint;
 import datadog.trace.api.experimental.DataStreamsContextCarrier;
 import datadog.trace.api.time.ControllableTimeSource;
+import datadog.trace.bootstrap.instrumentation.api.AgentSpan;
+import datadog.trace.bootstrap.instrumentation.api.AgentSpanContext;
 import datadog.trace.common.metrics.EventListener;
 import datadog.trace.common.metrics.Sink;
 import datadog.trace.core.DDCoreJavaSpecification;
@@ -1559,6 +1566,67 @@ void close() {
     }
   }
 
+  private DefaultDataStreamsMonitoring newDataStreamsMonitoring() {
+    return new DefaultDataStreamsMonitoring(
+        mock(Sink.class),
+        stubFeatures(true),
+        new ControllableTimeSource(),
+        () -> stubTraceConfig(true),
+        mock(DatastreamsPayloadWriter.class),
+        DEFAULT_BUCKET_DURATION_NANOS);
+  }
+
+  @Test
+  void setCheckpointTagsTheSpanWithThePathwayHash() {
+    DefaultDataStreamsMonitoring dataStreams = newDataStreamsMonitoring();
+
+    // Negative so the signed and unsigned string representations differ, proving the tag uses
+    // Long.toUnsignedString (pathway hashes are unsigned 64-bit values).
+    long hash = -1234567890123456789L;
+    PathwayContext pathwayContext = mock(PathwayContext.class);
+    when(pathwayContext.getHash()).thenReturn(hash);
+    AgentSpanContext spanContext = mock(AgentSpanContext.class);
+    when(spanContext.getPathwayContext()).thenReturn(pathwayContext);
+    AgentSpan span = mock(AgentSpan.class);
+    when(span.spanContext()).thenReturn(spanContext);
+    DataStreamsContext context = mock(DataStreamsContext.class);
+
+    dataStreams.setCheckpoint(span, context);
+
+    verify(pathwayContext).setCheckpoint(eq(context), any());
+    verify(span).setTag(DDTags.PATHWAY_HASH, Long.toUnsignedString(hash));
+  }
+
+  @Test
+  void setCheckpointDoesNotTagTheSpanWhenThePathwayHashIsZero() {
+    DefaultDataStreamsMonitoring dataStreams = newDataStreamsMonitoring();
+
+    PathwayContext pathwayContext = mock(PathwayContext.class);
+    when(pathwayContext.getHash()).thenReturn(0L);
+    AgentSpanContext spanContext = mock(AgentSpanContext.class);
+    when(spanContext.getPathwayContext()).thenReturn(pathwayContext);
+    AgentSpan span = mock(AgentSpan.class);
+    when(span.spanContext()).thenReturn(spanContext);
+
+    dataStreams.setCheckpoint(span, mock(DataStreamsContext.class));
+
+    verify(span, never()).setTag(eq(DDTags.PATHWAY_HASH), any(String.class));
+  }
+
+  @Test
+  void setCheckpointDoesNotTagTheSpanWhenThereIsNoPathwayContext() {
+    DefaultDataStreamsMonitoring dataStreams = newDataStreamsMonitoring();
+
+    AgentSpanContext spanContext = mock(AgentSpanContext.class);
+    when(spanContext.getPathwayContext()).thenReturn(null);
+    AgentSpan span = mock(AgentSpan.class);
+    when(span.spanContext()).thenReturn(spanContext);
+
+    dataStreams.setCheckpoint(span, mock(DataStreamsContext.class));
+
+    verify(span, never()).setTag(eq(DDTags.PATHWAY_HASH), any(String.class));
+  }
+
   static class CustomContextCarrier implements DataStreamsContextCarrier {
     private final Map<String, Object> data = new HashMap<>();