diff --git a/quic/QuicConstants.cpp b/quic/QuicConstants.cpp
index 74794563c..b795126fe 100644
--- a/quic/QuicConstants.cpp
+++ b/quic/QuicConstants.cpp
@@ -109,6 +109,8 @@ folly::StringPiece writeDataReasonString(WriteDataReason reason) {
       return "PathChallenge";
     case WriteDataReason::PING:
       return "Ping";
+    case WriteDataReason::DATAGRAM:
+      return "Datagram";
     case WriteDataReason::NO_WRITE:
       return "NoWrite";
   }
diff --git a/quic/QuicConstants.h b/quic/QuicConstants.h
index 27c65aa4f..98b692546 100644
--- a/quic/QuicConstants.h
+++ b/quic/QuicConstants.h
@@ -566,6 +566,7 @@ enum class WriteDataReason {
   RESET,
   PATHCHALLENGE,
   PING,
+  DATAGRAM,
 };
 
 enum class NoWriteReason {
diff --git a/quic/api/QuicTransportFunctions.cpp b/quic/api/QuicTransportFunctions.cpp
index d1cfbbc4b..35f0e43b0 100644
--- a/quic/api/QuicTransportFunctions.cpp
+++ b/quic/api/QuicTransportFunctions.cpp
@@ -1595,6 +1595,9 @@ WriteDataReason hasNonAckDataToWrite(const QuicConnectionStateBase& conn) {
   if (conn.pendingEvents.sendPing) {
     return WriteDataReason::PING;
   }
+  if (!conn.datagramState.writeBuffer.empty()) {
+    return WriteDataReason::DATAGRAM;
+  }
   return WriteDataReason::NO_WRITE;
 }
 
diff --git a/quic/api/test/QuicTransportFunctionsTest.cpp b/quic/api/test/QuicTransportFunctionsTest.cpp
index c77ea0dab..3614c19df 100644
--- a/quic/api/test/QuicTransportFunctionsTest.cpp
+++ b/quic/api/test/QuicTransportFunctionsTest.cpp
@@ -2893,6 +2893,15 @@ TEST_F(QuicTransportFunctionsTest, HasAppDataToWrite) {
   EXPECT_EQ(WriteDataReason::STREAM, hasNonAckDataToWrite(*conn));
 }
 
+TEST_F(QuicTransportFunctionsTest, HasDatagramsToWrite) {
+  auto conn = createConn();
+  conn->oneRttWriteCipher = test::createNoOpAead();
+  EXPECT_EQ(WriteDataReason::NO_WRITE, hasNonAckDataToWrite(*conn));
+  conn->datagramState.writeBuffer.emplace_back(
+      folly::IOBuf::copyBuffer("I'm an unreliable Datagram"));
+  EXPECT_EQ(WriteDataReason::DATAGRAM, hasNonAckDataToWrite(*conn));
+}
+
 TEST_F(QuicTransportFunctionsTest, UpdateConnectionCloneCounterAppData) {
   auto conn = createConn();
   ASSERT_EQ(