diff --git a/modules/rubiconBidAdapter.js b/modules/rubiconBidAdapter.js
index 69da9ab6db3..034b861f0f7 100644
--- a/modules/rubiconBidAdapter.js
+++ b/modules/rubiconBidAdapter.js
@@ -265,6 +265,7 @@ export const spec = {
     const containsTgI = /^tg_i/
 
     const orderedParams = [
+      'tpid_tdid',
       'account_id',
       'site_id',
       'zone_id',
@@ -367,6 +368,10 @@ export const spec = {
       'rf': _getPageUrl(bidRequest, bidderRequest)
     };
 
+    if ((bidRequest.userId || {}).tdid) {
+      data['tpid_tdid'] = bidRequest.userId.tdid;
+    }
+
     if (bidderRequest.gdprConsent) {
       // add 'gdpr' only if 'gdprApplies' is defined
       if (typeof bidderRequest.gdprConsent.gdprApplies === 'boolean') {
diff --git a/test/spec/modules/rubiconBidAdapter_spec.js b/test/spec/modules/rubiconBidAdapter_spec.js
index 53fa45e89ae..f3b244b1bc1 100644
--- a/test/spec/modules/rubiconBidAdapter_spec.js
+++ b/test/spec/modules/rubiconBidAdapter_spec.js
@@ -1060,6 +1060,19 @@ describe('the rubicon adapter', function () {
             expect(serverRequests).that.is.an('array').of.length(3);
           });
         });
+
+        describe('user id config', function() {
+          it('should send tpid_tdid when userId defines tdid', function () {
+            const clonedBid = clone(bidderRequest.bids[0]);
+            clonedBid.userId = {
+              tdid: 'abcd-efgh-ijkl-mnop-1234'
+            };
+            let [request] = spec.buildRequests([clonedBid], bidderRequest);
+            let data = parseQuery(request.data);
+
+            expect(data['tpid_tdid']).to.equal('abcd-efgh-ijkl-mnop-1234');
+          });
+        })
       });
 
       describe('for video requests', function () {