diff --git a/.gitleaksignore b/.gitleaksignore
index 743843dbe..6758264a1 100644
--- a/.gitleaksignore
+++ b/.gitleaksignore
@@ -25,3 +25,9 @@ debc75a97cfe551a69fd1e8694be483213322a9d:pact-contracts/pacts/letter-rendering/s
 4fa1923947bbff2387218d698d766cbb7c121a0f:pact-contracts/pacts/letter-rendering/supplier-api-letter-request-prepared.json:generic-api-key:10
 d005112adcfd286c3bef076214836dbb2fe8d0b5:.npmrc:npm-access-token:9
 d005112adcfd286c3bef076214836dbb2fe8d0b5:.npmrc:github-pat:7
+ff889d4c3f29da4468ecf1f05f467fe84d35b2a1:lambdas/supplier-mock/.aws-sam/build/SupplierMockFunction/index.js.map:ipv4:4
+ff889d4c3f29da4468ecf1f05f467fe84d35b2a1:lambdas/supplier-mock/.aws-sam/build/SupplierMockFunction/index.js:ipv4:63
+ff889d4c3f29da4468ecf1f05f467fe84d35b2a1:lambdas/supplier-mock/.aws-sam/build/SupplierMockFunction/index.js:ipv4:62
+ff889d4c3f29da4468ecf1f05f467fe84d35b2a1:lambdas/supplier-mock/.aws-sam/build/SupplierMockFunction/index.js:ipv4:60
+ff889d4c3f29da4468ecf1f05f467fe84d35b2a1:lambdas/supplier-mock/.aws-sam/build/SupplierMockFunction/index.js:ipv4:59
+ff889d4c3f29da4468ecf1f05f467fe84d35b2a1:lambdas/supplier-mock/.aws-sam/build/SupplierMockFunction/index.js:ipv4:24
diff --git a/lambdas/supplier-allocator/src/handler/__tests__/allocate-handler.test.ts b/lambdas/supplier-allocator/src/handler/__tests__/allocate-handler.test.ts
index eb1a3bfdb..b4606c4f6 100644
--- a/lambdas/supplier-allocator/src/handler/__tests__/allocate-handler.test.ts
+++ b/lambdas/supplier-allocator/src/handler/__tests__/allocate-handler.test.ts
@@ -69,7 +69,7 @@ function createPreparedV1Event(
       requestItemId: "requestItem1",
       requestItemPlanId: "requestItemPlan1",
       clientId: "client1",
-      campaignId: "campaign1",
+      campaignId: overrides.campaignId ?? "campaign1",
       templateId: "template1",
       url: overrides.url ?? "s3://letterDataBucket/letter1.pdf",
       sha256Hash:
@@ -230,6 +230,37 @@ describe("createSupplierAllocatorHandler", () => {
     });
   });
 
+  test("parses SNS notification and sends message to SQS queue for v2 event without a campaignId", async () => {
+    const preparedEvent = createPreparedV2Event({ campaignId: "" });
+    const evt: SQSEvent = createSQSEvent([
+      createSqsRecord("msg1", JSON.stringify(preparedEvent)),
+    ]);
+
+    setupDefaultMocks();
+    process.env.UPSERT_LETTERS_QUEUE_URL = "https://sqs.test.queue";
+
+    const handler = createSupplierAllocatorHandler(mockedDeps);
+    const result = await handler(evt, {} as any, {} as any);
+
+    expect(result).toBeDefined();
+    if (!result) throw new Error("expected BatchResponse, got void");
+
+    expect(result.batchItemFailures).toHaveLength(0);
+
+    expect(mockSqsClient.send).toHaveBeenCalledTimes(1);
+    const sendCall = (mockSqsClient.send as jest.Mock).mock.calls[0][0];
+    expect(sendCall).toBeInstanceOf(SendMessageCommand);
+
+    const messageBody = JSON.parse(sendCall.input.MessageBody);
+    expect(messageBody.letterEvent).toEqual(preparedEvent);
+    expect(messageBody.supplierSpec).toEqual({
+      supplierId: "supplier1",
+      specId: "spec1",
+      priority: 1,
+      billingId: "billing1",
+    });
+  });
+
   test("parses SNS notification and sends message to SQS queue for v1 event", async () => {
     const preparedEvent = createPreparedV1Event();
 
diff --git a/lambdas/supplier-allocator/src/handler/allocate-handler.ts b/lambdas/supplier-allocator/src/handler/allocate-handler.ts
index 2288fae12..8218a6db8 100644
--- a/lambdas/supplier-allocator/src/handler/allocate-handler.ts
+++ b/lambdas/supplier-allocator/src/handler/allocate-handler.ts
@@ -144,6 +144,27 @@ function emitMetrics(
   }
 }
 
+function emitSupCampaignClientMetric(
+  letterEvent: PreparedEvents,
+  supplier: string,
+  status: string,
+  deps: Deps,
+) {
+  const namespace = "supplier-allocator";
+  const { campaignId, clientId } = letterEvent.data;
+  const dimensions: Record<string, string> = {
+    Supplier: supplier,
+    ClientId: clientId,
+    CampaignId: campaignId || "unknown",
+  };
+  const metric: MetricEntry = {
+    key: status,
+    value: 1,
+    unit: Unit.Count,
+  };
+  deps.logger.info(buildEMFObject(namespace, dimensions, metric));
+}
+
 export default function createSupplierAllocatorHandler(deps: Deps): SQSHandler {
   return async (event: SQSEvent) => {
     const batchItemFailures: SQSBatchItemFailure[] = [];
@@ -153,8 +174,9 @@ export default function createSupplierAllocatorHandler(deps: Deps): SQSHandler {
     const tasks = event.Records.map(async (record) => {
       let supplier = "unknown";
       let priority = "unknown";
+      let letterEvent: PreparedEvents | undefined;
       try {
-        const letterEvent: unknown = JSON.parse(record.body);
+        letterEvent = JSON.parse(record.body) as PreparedEvents;
 
         deps.logger.info({
           description: "Extracted letter event",
@@ -163,8 +185,8 @@ export default function createSupplierAllocatorHandler(deps: Deps): SQSHandler {
 
         validateType(letterEvent);
 
-        const supplierSpec = getSupplier(letterEvent as PreparedEvents, deps);
-        await getSupplierFromConfig(letterEvent as PreparedEvents, deps);
+        const supplierSpec = getSupplier(letterEvent, deps);
+        await getSupplierFromConfig(letterEvent, deps);
 
         supplier = supplierSpec.supplierId;
         priority = String(supplierSpec.priority);
@@ -199,6 +221,12 @@ export default function createSupplierAllocatorHandler(deps: Deps): SQSHandler {
         );
 
         incrementMetric(perAllocationSuccess, supplier, priority);
+        emitSupCampaignClientMetric(
+          letterEvent,
+          supplier,
+          "supplier_Campaign_Client",
+          deps,
+        );
       } catch (error) {
         deps.logger.error({
           description: "Error processing allocation of record",