diff --git a/core/api/test-current.txt b/core/api/test-current.txt
index 5bd6ca827e293..7d9d0410282fd 100644
--- a/core/api/test-current.txt
+++ b/core/api/test-current.txt
@@ -1748,6 +1748,7 @@ package android.os {
 
   public class Process {
     method public static final int getThreadScheduler(int) throws java.lang.IllegalArgumentException;
+    method public static final int toSupplementalUid(int);
     field public static final int FIRST_APP_ZYGOTE_ISOLATED_UID = 90000; // 0x15f90
     field public static final int FIRST_ISOLATED_UID = 99000; // 0x182b8
     field public static final int LAST_APP_ZYGOTE_ISOLATED_UID = 98999; // 0x182b7
diff --git a/core/java/android/os/Process.java b/core/java/android/os/Process.java
index 2fe0622681127..17b5ec5ca01bd 100644
--- a/core/java/android/os/Process.java
+++ b/core/java/android/os/Process.java
@@ -929,6 +929,7 @@ public class Process {
      * @hide
      */
     @SystemApi(client = MODULE_LIBRARIES)
+    @TestApi
     public static final int toSupplementalUid(int uid) {
         return uid + (FIRST_SUPPLEMENTAL_UID - FIRST_APPLICATION_UID);
     }