diff --git a/services/web/app/src/Features/Analytics/AnalyticsManager.js b/services/web/app/src/Features/Analytics/AnalyticsManager.js
index 6c24b940ad..006995ba79 100644
--- a/services/web/app/src/Features/Analytics/AnalyticsManager.js
+++ b/services/web/app/src/Features/Analytics/AnalyticsManager.js
@@ -232,7 +232,7 @@ async function analyticsIdMiddleware(req, res, next) {
 
   if (sessionUser) {
     // ensure `session.analyticsId` is set to the user's `analyticsId`, and fallback to their `userId` for pre-analyticsId users
-    session.analyticsId = sessionUser.analyticsId || sessionUser.userId
+    session.analyticsId = sessionUser.analyticsId || sessionUser._id
   } else if (!session.analyticsId) {
     // generate an `analyticsId` if needed
     session.analyticsId = uuid.v4()
diff --git a/services/web/test/unit/src/Analytics/AnalyticsManagerTests.js b/services/web/test/unit/src/Analytics/AnalyticsManagerTests.js
index f1fef211cf..ba028937fe 100644
--- a/services/web/test/unit/src/Analytics/AnalyticsManagerTests.js
+++ b/services/web/test/unit/src/Analytics/AnalyticsManagerTests.js
@@ -198,7 +198,7 @@ describe('AnalyticsManager', function () {
 
     it('sets session.analyticsId with a logged in user in session having an analyticsId', async function () {
       this.req.session.user = {
-        userId: this.userId,
+        _id: this.userId,
         analyticsId: this.analyticsId,
       }
       await this.AnalyticsManager.analyticsIdMiddleware(
@@ -211,7 +211,7 @@ describe('AnalyticsManager', function () {
 
     it('sets session.analyticsId with a legacy user session without an analyticsId', async function () {
       this.req.session.user = {
-        userId: this.userId,
+        _id: this.userId,
         analyticsId: undefined,
       }
       await this.AnalyticsManager.analyticsIdMiddleware(
@@ -224,7 +224,7 @@ describe('AnalyticsManager', function () {
 
     it('updates session.analyticsId with a legacy user session without an analyticsId if different', async function () {
       this.req.session.user = {
-        userId: this.userId,
+        _id: this.userId,
         analyticsId: undefined,
       }
       this.req.analyticsId = 'foo'
@@ -238,7 +238,7 @@ describe('AnalyticsManager', function () {
 
     it('does not update session.analyticsId with a legacy user session without an analyticsId if same', async function () {
       this.req.session.user = {
-        userId: this.userId,
+        _id: this.userId,
         analyticsId: undefined,
       }
       this.req.analyticsId = this.userId