From Scotland, the 27-year-old was playing with Wasps earlier this season after making the move from Glasgow Warriors where he had been playing since 2017.
The Harlequins scrum-half is set to sign one-year extension to stay at Twickenham Stoop, according to The Rugby Paper.
The playmaker has already taken steps towards a new career after dumping his long-term advisors Esportif to sign up with entertainment specialists Insanity Group, who already represent Radio 1 DJ Jo Whiley and former Spandau Ballet frontman Martin Kemp.
Taunton-born Frost – who has previously represented Exeter in the A League – is one of several players who have been signed up by clubs across Europe in the wake of Wasps going into administration earlier this month.
Chiefs Director of Rugby, Rob Baxter, said: “We’ve known Dan for some time, having watched him play initially at Taunton and then down at the Cornish Pirates, where he was linking up with a few of our guys who were on dual-reg down there.
“He did very well at both those clubs, especially the Pirates, and it was off that form that he picked up his move to Wasps. At the time, it didn’t quite work for us to bring him into the club, but we’ve watched him closely ever since."
Former Wasps flanker Jack Willis is on the verge of joining his next club after his emotional exit from Wasps earlier this month.
Bristol Bears had been very keen to add the back-rower, but Pat Lam revealed this week that the club has no room within the salary cap to complete the signing.
RUCK sources indicate although a move to Saints is likely, Willis would only sign until the end of the season with the view to rejoining Wasps in the Championship next season.
South Africa prop Wilco Louw has put pen to paper on a deal to head home and join the Bulls in July 2023, as he brings an end to his time at Harlequins.
The outstanding tighthead prop, who was part of the Quins squad that won the Premiership title in 2020/21, has opted to move to Pretoria next year.
George has played all of his senior career for Saracens, making his debut in 2009. He remained at the club when they were relegated to the Championship in 2020.
In search of a high-level international centre for next season, Stade Francais have entered advanced talks with England and Harlequins playmaker Joe Marchant.
INFO MIDOL - L'ouvreur et capitaine du pays de Galles Dan Biggar (33 ans, 105 sélections) s'est engagé avec le Rugby Club Toulonnais pour le reste de la saison.✍️
rugbyrama.fr/rugby/transfer…
Putting @dannycare straight into the hot seat 😅
But perfectly balanced from the @Harlequins man
"It's a hard job these referees have to do" ⚖️
#RugbyTonight