diff --git a/testing/web-platform/tests/fledge/tentative/resources/fledge_http_server_util.py b/testing/web-platform/tests/fledge/tentative/resources/fledge_http_server_util.py
index b7456282d8103..179262d339268 100644
--- a/testing/web-platform/tests/fledge/tentative/resources/fledge_http_server_util.py
+++ b/testing/web-platform/tests/fledge/tentative/resources/fledge_http_server_util.py
@@ -119,7 +119,8 @@ def decode_trusted_scoring_signals_params(request):
             pair[0] == 'adSizes' or
             pair[0] == 'adComponentSizes' or
             pair[0] == 'adBuyer' or
-            pair[0] == 'adComponentBuyer'):
+            pair[0] == 'adComponentBuyer' or
+            pair[0] == 'adBuyerAndSellerReportingIds'):
           continue
       raise ValueError("Unexpected query parameter: " + param)
 
diff --git a/testing/web-platform/tests/fledge/tentative/trusted-scoring-signals.https.window.js b/testing/web-platform/tests/fledge/tentative/trusted-scoring-signals.https.window.js
index 0c3b4054395a9..ea820d3acf54e 100644
--- a/testing/web-platform/tests/fledge/tentative/trusted-scoring-signals.https.window.js
+++ b/testing/web-platform/tests/fledge/tentative/trusted-scoring-signals.https.window.js
@@ -809,9 +809,13 @@ subsetTest(promise_test, async test => {
 
   const bidder_origin = OTHER_ORIGIN1;
 
-  await joinCrossOriginInterestGroup(
-      test, uuid, bidder_origin,
-      {ads: [{renderURL: renderURL, creativeScanningMetadata: 'hello'}]});
+  await joinCrossOriginInterestGroup(test, uuid, bidder_origin, {
+    ads: [{
+      renderURL: renderURL,
+      creativeScanningMetadata: 'hello',
+      buyerAndSellerReportingId: 'chair'
+    }]
+  });
 
   const scoreAdBody = `
     ${makeParseHelper(renderURL)}
@@ -819,6 +823,8 @@ subsetTest(promise_test, async test => {
       throw 'Wrong URL';
     if (parsed.get('adCreativeScanningMetadata') !== 'hello')
       throw 'Wrong creative scanning metadata';
+    if (parsed.get('adBuyerAndSellerReportingIds') !== 'chair')
+      throw 'Wrong BSRID';
     if (parsed.get('adSizes') !== ',')
       throw 'Wrong adSizes';
     if (parsed.get('adBuyer') !== '${bidder_origin}')
@@ -852,7 +858,7 @@ subsetTest(promise_test, async test => {
 
   await joinCrossOriginInterestGroup(
       test, uuid, bidder_origin,
-      {ads: [{renderURL: renderURL}]});
+      {ads: [{renderURL: renderURL, buyerAndSellerReportingId: 'sofa'}]});
 
   const scoreAdBody = `
     ${makeParseHelper(renderURL)}
@@ -860,6 +866,8 @@ subsetTest(promise_test, async test => {
       throw 'Wrong URL';
     if (parsed.get('adCreativeScanningMetadata') !== '')
       throw 'Wrong creative scanning metadata';
+    if (parsed.get('adBuyerAndSellerReportingIds') !== 'sofa')
+      throw 'Wrong BSRID';
     if (parsed.get('adSizes') !== ',')
       throw 'Wrong adSizes';
     if (parsed.get('adBuyer') !== '${bidder_origin}')
@@ -899,6 +907,8 @@ subsetTest(promise_test, async test => {
       throw 'Wrong URL';
     if (parsed.has('adCreativeScanningMetadata'))
       throw 'Unexpected creative scanning metadata';
+    if (parsed.has('adBuyerAndSellerReportingIds'))
+      throw 'Unexpected BSRID';
     if (parsed.has('adSizes'))
       throw 'Unexpected adSizes';
     if (parsed.has('adBuyer'))
@@ -958,6 +968,8 @@ subsetTest(promise_test, async test => {
       throw 'Wrong URL';
     if (parsed.get('adCreativeScanningMetadata') !== 'hello')
       throw 'Wrong creative scanning metadata';
+    if (parsed.get('adBuyerAndSellerReportingIds') !== '')
+      throw 'Wrong BSRID';
     if (parsed.get('adSizes') !== '100px,10sh')
       throw 'Wrong adSizes';
     if (parsed.get('adBuyer') !== '${window.location.origin}')
@@ -1035,6 +1047,8 @@ subsetTest(promise_test, async test => {
       throw 'Wrong URL';
     if (parsed.get('adCreativeScanningMetadata') !== 'hello')
       throw 'Wrong creative scanning metadata';
+    if (parsed.get('adBuyerAndSellerReportingIds') !== '')
+      throw 'Wrong BSRID';
     if (parsed.get('adSizes') !== ',')
       throw 'Wrong adSizes';
     if (parsed.get('adBuyer') !== '${window.location.origin}')