diff --git a/proto/src/metrics_constants.proto b/proto/src/metrics_constants.proto
index 28f26c6fa55b8..3cadff242e039 100644
--- a/proto/src/metrics_constants.proto
+++ b/proto/src/metrics_constants.proto
@@ -4545,7 +4545,8 @@ message MetricsEvent {
     // OS: O MR
     AUTOFILL_SERVICE_DISABLED_SELF = 1135;
 
-    // Counter showing how long it took (in ms) to show the autofill UI after a field was focused
+    // Reports how long it took to show the autofill UI after a field was focused
+    // Tag FIELD_AUTOFILL_DURATION: Duration in ms
     // Tag FIELD_AUTOFILL_SERVICE: Package of service that processed the request
     // Package: Package of the autofill service
     // OS: O MR
@@ -4584,6 +4585,9 @@ message MetricsEvent {
     // logged when we cancel an app transition.
     APP_TRANSITION_CANCELLED = 1144;
 
+    // Tag of a field representing a duration on autofill-related metrics.
+    FIELD_AUTOFILL_DURATION = 1145;
+
     // ---- End O-MR1 Constants, all O-MR1 constants go above this line ----
 
     // ACTION: Stop an app and turn on background check
diff --git a/services/autofill/java/com/android/server/autofill/Session.java b/services/autofill/java/com/android/server/autofill/Session.java
index c5cf970eab79b..1f0e51c694aaa 100644
--- a/services/autofill/java/com/android/server/autofill/Session.java
+++ b/services/autofill/java/com/android/server/autofill/Session.java
@@ -1397,7 +1397,7 @@ final class Session implements RemoteFillService.FillServiceCallbacks, ViewState
                 mUiLatencyHistory.log(historyLog.toString());
 
                 final LogMaker metricsLog = newLogMaker(MetricsEvent.AUTOFILL_UI_LATENCY)
-                        .setCounterValue((int) duration);
+                        .addTaggedData(MetricsEvent.FIELD_AUTOFILL_DURATION, duration);
                 mMetricsLogger.write(metricsLog);
             }
         }