diff --git a/src/sentry/issues/producer.py b/src/sentry/issues/producer.py
index 8c4944969966e..962baa2e0a5cc 100644
--- a/src/sentry/issues/producer.py
+++ b/src/sentry/issues/producer.py
@@ -66,9 +66,9 @@ def produce_occurrence_to_kafka(
 
     partition_key = None
     if occurrence and occurrence.fingerprint:
-        partition_key = occurrence.fingerprint[0].encode()
+        partition_key = f"{occurrence.fingerprint[0]}-{occurrence.project_id}".encode()
     elif status_change and status_change.fingerprint:
-        partition_key = status_change.fingerprint[0].encode()
+        partition_key = f"{status_change.fingerprint[0]}-{status_change.project_id}".encode()
     payload = KafkaPayload(partition_key, json.dumps(payload_data).encode("utf-8"), [])
     if settings.SENTRY_EVENTSTREAM != "sentry.eventstream.kafka.KafkaEventStream":
         # If we're not running Kafka then we're just in dev.
diff --git a/tests/sentry/issues/test_producer.py b/tests/sentry/issues/test_producer.py
index b57e8938f829a..1c75bcaa2318f 100644
--- a/tests/sentry/issues/test_producer.py
+++ b/tests/sentry/issues/test_producer.py
@@ -105,7 +105,7 @@ def test_payload_sent_to_kafka_with_partition_key(
         mock_produce.assert_called_once_with(
             ArroyoTopic(name="ingest-occurrences"),
             KafkaPayload(
-                occurrence.fingerprint[0].encode(),
+                f"{occurrence.fingerprint[0]}-{occurrence.project_id}".encode(),
                 json.dumps({"mock_data": "great"}).encode("utf-8"),
                 [],
             ),
@@ -402,7 +402,7 @@ def test_payload_sent_to_kafka_with_partition_key(
         mock_produce.assert_called_once_with(
             ArroyoTopic(name="ingest-occurrences"),
             KafkaPayload(
-                status_change.fingerprint[0].encode(),
+                f"{status_change.fingerprint[0]}-{status_change.project_id}".encode(),
                 json.dumps({"mock_data": "great"}).encode("utf-8"),
                 [],
             ),