diff --git a/packages/react-native/Libraries/Network/RCTNetworking.android.js b/packages/react-native/Libraries/Network/RCTNetworking.android.js
index d5d782a2100..798ee2177de 100644
--- a/packages/react-native/Libraries/Network/RCTNetworking.android.js
+++ b/packages/react-native/Libraries/Network/RCTNetworking.android.js
@@ -59,7 +59,7 @@ const RCTNetworking = {
 
   sendRequest(
     method: string,
-    trackingName: string,
+    trackingName: ?string,
     url: string,
     headers: Object,
     data: RequestBody,
diff --git a/packages/react-native/Libraries/Network/RCTNetworking.ios.js b/packages/react-native/Libraries/Network/RCTNetworking.ios.js
index 4d528eebdba..e5b2dd572ff 100644
--- a/packages/react-native/Libraries/Network/RCTNetworking.ios.js
+++ b/packages/react-native/Libraries/Network/RCTNetworking.ios.js
@@ -29,7 +29,7 @@ const RCTNetworking = {
 
   sendRequest(
     method: string,
-    trackingName: string,
+    trackingName: ?string,
     url: string,
     headers: {...},
     data: RequestBody,
diff --git a/packages/react-native/Libraries/Network/RCTNetworking.js.flow b/packages/react-native/Libraries/Network/RCTNetworking.js.flow
index 6f8f64a6e91..75b67d51989 100644
--- a/packages/react-native/Libraries/Network/RCTNetworking.js.flow
+++ b/packages/react-native/Libraries/Network/RCTNetworking.js.flow
@@ -25,7 +25,7 @@ declare const RCTNetworking: interface {
 
   sendRequest(
     method: string,
-    trackingName: string,
+    trackingName: ?string,
     url: string,
     headers: {...},
     data: RequestBody,
diff --git a/packages/react-native/Libraries/Network/XMLHttpRequest_new.js b/packages/react-native/Libraries/Network/XMLHttpRequest_new.js
index 6206936f545..8e4b91e6294 100644
--- a/packages/react-native/Libraries/Network/XMLHttpRequest_new.js
+++ b/packages/react-native/Libraries/Network/XMLHttpRequest_new.js
@@ -152,7 +152,7 @@ class XMLHttpRequest extends EventTarget {
   _sent: boolean;
   _url: ?string = null;
   _timedOut: boolean = false;
-  _trackingName: string = 'unknown';
+  _trackingName: ?string = null;
   _incrementalEvents: boolean = false;
   _startTime: ?number = null;
   _performanceLogger: IPerformanceLogger = GlobalPerformanceLogger;
@@ -478,7 +478,7 @@ class XMLHttpRequest extends EventTarget {
   /**
    * Custom extension for tracking origins of request.
    */
-  setTrackingName(trackingName: string): XMLHttpRequest {
+  setTrackingName(trackingName: ?string): XMLHttpRequest {
     this._trackingName = trackingName;
     return this;
   }
@@ -560,8 +560,7 @@ class XMLHttpRequest extends EventTarget {
     }
 
     const doSend = () => {
-      const friendlyName =
-        this._trackingName !== 'unknown' ? this._trackingName : this._url;
+      const friendlyName = this._trackingName ?? this._url;
       this._perfKey = 'network_XMLHttpRequest_' + String(friendlyName);
       this._performanceLogger.startTimespan(this._perfKey);
       this._startTime = performance.now();
diff --git a/packages/react-native/Libraries/Network/XMLHttpRequest_old.js b/packages/react-native/Libraries/Network/XMLHttpRequest_old.js
index a7d68219967..9b9ed75341b 100644
--- a/packages/react-native/Libraries/Network/XMLHttpRequest_old.js
+++ b/packages/react-native/Libraries/Network/XMLHttpRequest_old.js
@@ -130,7 +130,7 @@ class XMLHttpRequest extends (EventTarget(...XHR_EVENTS): typeof EventTarget) {
   _sent: boolean;
   _url: ?string = null;
   _timedOut: boolean = false;
-  _trackingName: string = 'unknown';
+  _trackingName: ?string = null;
   _incrementalEvents: boolean = false;
   _startTime: ?number = null;
   _performanceLogger: IPerformanceLogger = GlobalPerformanceLogger;
@@ -453,7 +453,7 @@ class XMLHttpRequest extends (EventTarget(...XHR_EVENTS): typeof EventTarget) {
   /**
    * Custom extension for tracking origins of request.
    */
-  setTrackingName(trackingName: string): XMLHttpRequest {
+  setTrackingName(trackingName: ?string): XMLHttpRequest {
     this._trackingName = trackingName;
     return this;
   }
@@ -535,8 +535,7 @@ class XMLHttpRequest extends (EventTarget(...XHR_EVENTS): typeof EventTarget) {
     }
 
     const doSend = () => {
-      const friendlyName =
-        this._trackingName !== 'unknown' ? this._trackingName : this._url;
+      const friendlyName = this._trackingName ?? this._url;
       this._perfKey = 'network_XMLHttpRequest_' + String(friendlyName);
       this._performanceLogger.startTimespan(this._perfKey);
       this._startTime = performance.now();
diff --git a/packages/react-native/Libraries/__tests__/__snapshots__/public-api-test.js.snap b/packages/react-native/Libraries/__tests__/__snapshots__/public-api-test.js.snap
index 2c60e5ffe97..37fd09f70b3 100644
--- a/packages/react-native/Libraries/__tests__/__snapshots__/public-api-test.js.snap
+++ b/packages/react-native/Libraries/__tests__/__snapshots__/public-api-test.js.snap
@@ -5985,7 +5985,7 @@ exports[`public API should not change unintentionally Libraries/Network/RCTNetwo
   ): EventSubscription,
   sendRequest(
     method: string,
-    trackingName: string,
+    trackingName: ?string,
     url: string,
     headers: { ... },
     data: RequestBody,
@@ -6073,7 +6073,7 @@ declare class XMLHttpRequest extends EventTarget {
   getAllResponseHeaders(): ?string;
   getResponseHeader(header: string): ?string;
   setRequestHeader(header: string, value: any): void;
-  setTrackingName(trackingName: string): XMLHttpRequest;
+  setTrackingName(trackingName: ?string): XMLHttpRequest;
   setPerformanceLogger(performanceLogger: IPerformanceLogger): XMLHttpRequest;
   open(method: string, url: string, async: ?boolean): void;
   send(data: any): void;
@@ -6156,7 +6156,7 @@ declare class XMLHttpRequest extends EventTarget {
   getAllResponseHeaders(): ?string;
   getResponseHeader(header: string): ?string;
   setRequestHeader(header: string, value: any): void;
-  setTrackingName(trackingName: string): XMLHttpRequest;
+  setTrackingName(trackingName: ?string): XMLHttpRequest;
   setPerformanceLogger(performanceLogger: IPerformanceLogger): XMLHttpRequest;
   open(method: string, url: string, async: ?boolean): void;
   send(data: any): void;