diff --git a/internal/congestion/cubic_sender.go b/internal/congestion/cubic_sender.go
index 33ef491f..a2b0af51 100644
--- a/internal/congestion/cubic_sender.go
+++ b/internal/congestion/cubic_sender.go
@@ -89,7 +89,7 @@ func (c *cubicSender) TimeUntilSend(bytesInFlight protocol.ByteCount) time.Durat
 			return 0
 		}
 	}
-	delay := c.rttStats.SmoothedRTT() / time.Duration(2*c.GetCongestionWindow())
+	delay := c.rttStats.SmoothedRTT() * time.Duration(protocol.DefaultTCPMSS) / time.Duration(2*c.GetCongestionWindow())
 	if !c.InSlowStart() { // adjust delay, such that it's 1.25*cwd/rtt
 		delay = delay * 8 / 5
 	}