diff --git a/services/core/java/com/android/server/apphibernation/AppHibernationService.java b/services/core/java/com/android/server/apphibernation/AppHibernationService.java
index 5a99e0e77a6ce..e8b3a24b751d8 100644
--- a/services/core/java/com/android/server/apphibernation/AppHibernationService.java
+++ b/services/core/java/com/android/server/apphibernation/AppHibernationService.java
@@ -362,6 +362,7 @@ public final class AppHibernationService extends SystemService {
             UserLevelState pkgState) {
         Trace.traceBegin(Trace.TRACE_TAG_SYSTEM_SERVER, "unhibernatePackage");
         pkgState.hibernated = false;
+        pkgState.lastUnhibernatedMs = System.currentTimeMillis();
         Trace.traceEnd(Trace.TRACE_TAG_SYSTEM_SERVER);
     }
 
@@ -383,6 +384,7 @@ public final class AppHibernationService extends SystemService {
     private void unhibernatePackageGlobally(@NonNull String packageName, GlobalLevelState state) {
         Trace.traceBegin(Trace.TRACE_TAG_SYSTEM_SERVER, "unhibernatePackageGlobally");
         state.hibernated = false;
+        state.lastUnhibernatedMs = System.currentTimeMillis();
         Trace.traceEnd(Trace.TRACE_TAG_SYSTEM_SERVER);
     }
 
diff --git a/services/core/java/com/android/server/apphibernation/GlobalLevelState.java b/services/core/java/com/android/server/apphibernation/GlobalLevelState.java
index baa84b7070ff3..f4433a7fa5f63 100644
--- a/services/core/java/com/android/server/apphibernation/GlobalLevelState.java
+++ b/services/core/java/com/android/server/apphibernation/GlobalLevelState.java
@@ -16,18 +16,28 @@
 
 package com.android.server.apphibernation;
 
+import android.annotation.CurrentTimeMillisLong;
+
+import java.text.SimpleDateFormat;
+
 /**
  * Data class that contains global hibernation state for a package.
  */
 final class GlobalLevelState {
+    // Only show day for privacy purposes.
+    private static final SimpleDateFormat DATE_FORMAT = new SimpleDateFormat("yyyy-MM-dd");
+
     public String packageName;
     public boolean hibernated;
+    @CurrentTimeMillisLong
+    public long lastUnhibernatedMs;
 
     @Override
     public String toString() {
         return "GlobalLevelState{"
                 + "packageName='" + packageName + '\''
-                + ", hibernated=" + hibernated
+                + ", hibernated=" + hibernated + '\''
+                + ", lastUnhibernated=" + DATE_FORMAT.format(lastUnhibernatedMs)
                 + '}';
     }
 }
diff --git a/services/core/java/com/android/server/apphibernation/UserLevelState.java b/services/core/java/com/android/server/apphibernation/UserLevelState.java
index 272d3d1122a14..b75b19d8df744 100644
--- a/services/core/java/com/android/server/apphibernation/UserLevelState.java
+++ b/services/core/java/com/android/server/apphibernation/UserLevelState.java
@@ -16,18 +16,27 @@
 
 package com.android.server.apphibernation;
 
+import android.annotation.CurrentTimeMillisLong;
+
+import java.text.SimpleDateFormat;
+
 /**
  * Data class that contains hibernation state info of a package for a user.
  */
 final class UserLevelState {
+    private static final SimpleDateFormat DATE_FORMAT = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss");
+
     public String packageName;
     public boolean hibernated;
+    @CurrentTimeMillisLong
+    public long lastUnhibernatedMs;
 
     @Override
     public String toString() {
         return "UserLevelState{"
                 + "packageName='" + packageName + '\''
-                + ", hibernated=" + hibernated
+                + ", hibernated=" + hibernated + '\''
+                + ", lastUnhibernated=" + DATE_FORMAT.format(lastUnhibernatedMs)
                 + '}';
     }
 }