Mike Garafolo of NFL Network reported the news, though no terms of the deal are available at this time.
Austin, 27, spent the 2018 season in Dallas after playing five years for the Rams. He recorded eight receptions for 140 yards and two touchdowns while appearing in seven games.
The West Virginia product has yet to live up to his billing after being the No. 8 pick in the 2013 draft. He's never put up more than 509 receiving yards or reached 1,000 total yards. Still, the Cowboys offensive staff valued his potential impact.
"Tavon has the unique ability of making big plays with not playing every game," former Cowboys offensive coordinator Scott Linehan told reporters in December. "He's a guy that goes in there, he's going to feel like a guy with fresh legs on the field. ... He looks like a guy that's ready to go out and give us a big jolt in the passing game with his threat, being able to get downfield. ... He's going to be a guy we can put in at any receiver position to help us have potential for some explosive plays."
The Cowboys may use Austin more regularly in their offense next season after losing receiver Cole Beasley to the Buffalo Bills in free agency. Dallas has been mostly quiet on the open market and does not have its own first-round pick, so Austin has a real shot at starting in the slot.
Given his total lack of production the last two years in particular, the Cowboys are betting against recent trends in a big way.