diff --git a/lib/middleware.js b/lib/middleware.js
index a8ef630c..c581c60f 100644
--- a/lib/middleware.js
+++ b/lib/middleware.js
@@ -28,6 +28,7 @@ module.exports = function(srf, logger) {
     registrar,
     lookupClientByAccountAndUsername
   }  = srf.locals.dbHelpers;
+  const {addKey} = srf.locals.dbHelpers;
   const {
     writeAlerts,
     AlertType
@@ -142,6 +143,14 @@ module.exports = function(srf, logger) {
       rootSpan
     };
 
+    /* write a short-lived Redis key mapping the original Call-ID (X-CID) to the traceId,
+       so sbc-inbound can look it up for CDRs even when a CANCEL is sent to sbc-inbound */
+    const externalCallId = req.get('X-CID');
+    if (externalCallId) {
+      addKey(`callid:${externalCallId}`, traceId, 300)
+        .catch((err) => logger.error(err, 'createRootSpan: error writing traceId to Redis'));
+    }
+
     /**
      * end the span on final failure or cancel from caller;
      * otherwise it will be closed when sip dialog is destroyed
diff --git a/lib/session/call-session.js b/lib/session/call-session.js
index 099325c5..d1bc8cd9 100644
--- a/lib/session/call-session.js
+++ b/lib/session/call-session.js
@@ -1495,7 +1495,12 @@ class CallSession extends Emitter {
     else if (opts.call_status === CallStatus.NoAnswer) {
       if (this.direction === CallDirection.Inbound) {
         if (this.res && !this.res.finalResponseSent) {
-          this.res.send(503);
+          const traceId = this.req?.locals?.traceId;
+          this.res.send(503, {
+            headers: {
+              ...(traceId && {'X-Trace-ID': traceId})
+            }
+          });
           this._callReleased();
         }
       }
@@ -2530,10 +2535,12 @@ Duration=${duration} `
           // Send SIP error response immediately for inbound calls
           if (this.res && !this.res.finalResponseSent) {
             this.logger.info(`Sending ${err.status} response to SBC due to SipError`);
+            const traceId = this.req?.locals?.traceId;
             this.res.send(err.status, {
               headers: {
                 'X-Reason': `endpoint allocation failure: ${err.reason || 'Endpoint Allocation Failed'}`,
-                ...(sipReasonHeader && {'Reason': sipReasonHeader})
+                ...(sipReasonHeader && {'Reason': sipReasonHeader}),
+                ...(traceId && {'X-Trace-ID': traceId})
               }
             });
             this._notifyCallStatusChange({
diff --git a/lib/session/inbound-call-session.js b/lib/session/inbound-call-session.js
index a905f4bd..ef69c556 100644
--- a/lib/session/inbound-call-session.js
+++ b/lib/session/inbound-call-session.js
@@ -51,12 +51,14 @@ class InboundCallSession extends CallSession {
 
   _onTasksDone() {
     if (!this.res.finalResponseSent) {
+      const traceId = this.req.locals.traceId;
       if (this._mediaServerFailure) {
         this.rootSpan.setAttributes({'call.termination': 'media server failure'});
         this.logger.info('InboundCallSession:_onTasksDone generating 480 due to media server failure');
         this.res.send(480, {
           headers: {
-            'X-Reason': 'crankback: media server failure'
+            'X-Reason': 'crankback: media server failure',
+            ...(traceId && {'X-Trace-ID': traceId})
           }
         });
       }
@@ -69,14 +71,19 @@ class InboundCallSession extends CallSession {
         this.res.send(status, {
           headers: {
             'X-Reason': `endpoint allocation failure: ${reason}`,
-            ...(sipReasonHeader && {'Reason': sipReasonHeader})
+            ...(sipReasonHeader && {'Reason': sipReasonHeader}),
+            ...(traceId && {'X-Trace-ID': traceId})
           }
         });
       }
       else {
         this.rootSpan.setAttributes({'call.termination': 'tasks completed without answering call'});
         this.logger.info('InboundCallSession:_onTasksDone auto-generating non-success response to invite');
-        this.res.send(603);
+        this.res.send(603, {
+          headers: {
+            ...(traceId && {'X-Trace-ID': traceId})
+          }
+        });
       }
     }
     this.req.removeAllListeners('cancel');