It covers 240 miles/385 km to drive non-stop from Dallas to Houston by car. The total Dallas to Houston drive time is 3 hours and 50 minutes. However, the travel time between the two cities may vary depending upon the speed of a car. For instance, it takes almost 8 hours at 30 mph (48km/h) average speed whereas 4 hours at 60 mph (97 km/h) average speed. In addition, you can opt for two different routes for the Dallas to Houston drive; I-45 S and Hwy 6 S from which I-45 S is considered to be the quickest route whereas Hwy 6 S route takes more time comparatively.