Caltrans said both directions opened to vehicles only on Sunday, and trucks are still being turned around at Colfax and Stateline. Caltrans said chains are still required over the summit.
Both eastbound and westbound lanes of I-80 were closed on Saturday due to heavy snow in the Sierra, with close to zero visibility, according to Caltrans.
The agency said motorists were being turned away in both cities, Kingvale for eastbound travelers and Truckee for westbound.
Caltrans is reminding drivers to watch their speed and snow removal equipment.