diff --git a/federationapi/consumers/receipts.go b/federationapi/consumers/receipts.go
index b539e103e..2c9d79bcb 100644
--- a/federationapi/consumers/receipts.go
+++ b/federationapi/consumers/receipts.go
@@ -90,7 +90,7 @@ func (t *OutputReceiptConsumer) onMessage(ctx context.Context, msg *nats.Msg) bo
 		return true
 	}
 
-	timestamp, err := strconv.ParseUint(msg.Header.Get("timestamp"), 0, 10)
+	timestamp, err := strconv.ParseUint(msg.Header.Get("timestamp"), 10, 64)
 	if err != nil {
 		// If the message was invalid, log it and move on to the next message in the stream
 		log.WithError(err).Errorf("EDU output log: message parse failure")
diff --git a/syncapi/consumers/receipts.go b/syncapi/consumers/receipts.go
index f83dadace..83156cf93 100644
--- a/syncapi/consumers/receipts.go
+++ b/syncapi/consumers/receipts.go
@@ -87,7 +87,7 @@ func (s *OutputReceiptEventConsumer) onMessage(ctx context.Context, msg *nats.Ms
 		Type:    msg.Header.Get("type"),
 	}
 
-	timestamp, err := strconv.ParseUint(msg.Header.Get("timestamp"), 0, 10)
+	timestamp, err := strconv.ParseUint(msg.Header.Get("timestamp"), 10, 64)
 	if err != nil {
 		// If the message was invalid, log it and move on to the next message in the stream
 		log.WithError(err).Errorf("output log: message parse failure")