diff --git a/core/api/system-current.txt b/core/api/system-current.txt
index e225bb4..d971f8b 100644
--- a/core/api/system-current.txt
+++ b/core/api/system-current.txt
@@ -16196,6 +16196,7 @@
     method @Nullable @RequiresPermission(android.Manifest.permission.INTERACT_ACROSS_USERS) public android.content.ComponentName getAndUpdateDefaultRespondViaMessageApplication();
     method @RequiresPermission(android.Manifest.permission.READ_PRIVILEGED_PHONE_STATE) public void getCallForwarding(int, @NonNull java.util.concurrent.Executor, @NonNull android.telephony.TelephonyManager.CallForwardingInfoCallback);
     method @RequiresPermission(android.Manifest.permission.READ_PRIVILEGED_PHONE_STATE) public void getCallWaitingStatus(@NonNull java.util.concurrent.Executor, @NonNull java.util.function.Consumer<java.lang.Integer>);
+    method @FlaggedApi("com.android.internal.telephony.flags.carrier_id_from_carrier_identifier") @RequiresPermission(android.Manifest.permission.READ_PRIVILEGED_PHONE_STATE) @WorkerThread public int getCarrierIdFromCarrierIdentifier(@NonNull android.service.carrier.CarrierIdentifier);
     method @Nullable @RequiresPermission(android.Manifest.permission.READ_PRIVILEGED_PHONE_STATE) public android.telephony.ImsiEncryptionInfo getCarrierInfoForImsiEncryption(int);
     method public java.util.List<java.lang.String> getCarrierPackageNamesForIntent(android.content.Intent);
     method @RequiresPermission(android.Manifest.permission.READ_PRIVILEGED_PHONE_STATE) public java.util.List<java.lang.String> getCarrierPackageNamesForIntentAndPhone(android.content.Intent, int);
diff --git a/telephony/java/android/telephony/TelephonyManager.java b/telephony/java/android/telephony/TelephonyManager.java
index e22d75e..ad5d42a 100644
--- a/telephony/java/android/telephony/TelephonyManager.java
+++ b/telephony/java/android/telephony/TelephonyManager.java
@@ -19599,4 +19599,37 @@
             throw ex.rethrowAsRuntimeException();
         }
     }
+
+    /**
+     * Returns carrier id maps to the passing CarrierIdentifier.
+     * To recognize a carrier (including MVNO) as a first-class identity,
+     * Android assigns each carrier with a canonical integer a.k.a. carrier id.
+     * The carrier ID is an Android platform-wide identifier for a carrier.
+     * AOSP maintains carrier ID assignments in
+     * <a href="https://android.googlesource.com/platform/packages/providers/TelephonyProvider/+/master/assets/latest_carrier_id/carrier_list.textpb">here</a>
+     *
+     * @param carrierIdentifier {@link CarrierIdentifier}
+     *
+     * @return Carrier id. Return {@link #UNKNOWN_CARRIER_ID} if the carrier cannot be identified.
+     * @throws UnsupportedOperationException If the device does not have
+     *          {@link PackageManager#FEATURE_TELEPHONY_SUBSCRIPTION}.
+     *
+     * @hide
+     */
+    @FlaggedApi(Flags.FLAG_CARRIER_ID_FROM_CARRIER_IDENTIFIER)
+    @SystemApi
+    @WorkerThread
+    @RequiresFeature(PackageManager.FEATURE_TELEPHONY_SUBSCRIPTION)
+    @RequiresPermission(android.Manifest.permission.READ_PRIVILEGED_PHONE_STATE)
+    public int getCarrierIdFromCarrierIdentifier(@NonNull CarrierIdentifier carrierIdentifier) {
+        try {
+            ITelephony service = getITelephony();
+            if (service != null) {
+                return service.getCarrierIdFromIdentifier(carrierIdentifier);
+            }
+        } catch (RemoteException ex) {
+            // This could happen if binder process crashes.
+        }
+        return UNKNOWN_CARRIER_ID;
+    }
 }
diff --git a/telephony/java/com/android/internal/telephony/ITelephony.aidl b/telephony/java/com/android/internal/telephony/ITelephony.aidl
index d22e9fa..294c93c 100644
--- a/telephony/java/com/android/internal/telephony/ITelephony.aidl
+++ b/telephony/java/com/android/internal/telephony/ITelephony.aidl
@@ -3519,4 +3519,15 @@
     * @hide
     */
     void setNtnSmsSupported(boolean ntnSmsSupported);
+
+    /**
+     * Returns carrier id maps to the passing {@link CarrierIdentifier}.
+     *
+     * @param {@link CarrierIdentifier}.
+     *
+     * @return carrier id from passing {@link CarrierIdentifier} or {@link #UNKNOWN_CARRIER_ID}
+     * if the carrier cannot be identified
+     * @hide
+     */
+    int getCarrierIdFromIdentifier(in CarrierIdentifier carrierIdentifier);
 }