The St Mirren legend was an integral part of the Jags side that claimed the First Division crown last season but found himself well down the pecking order following a host of summer signings by boss Alan Archibald.
With his first-team chances limited, the midfielder moved to SPFL Championship side Dumbarton on loan earlier this season, where he has become a key player for Ian Murray's side as they have once again impressed in Scotland's second tier.
A return to the Rock could now be on the cards for Murray after Thistle terminated his contract by mutual consent on the day that his Sons loan deal came to an end.
Also heading out of Firhill is youngster Gerry O'Donnell, who joined the club last season and has spent recent months on loan at Maryhill Juniors.
A Thistle spokesman said: "We wish both Hugh and Gerry the very best for the future and thank them for their contribution while at Firhill.
"Both players are now free agents and can sign for other clubs."
Boss Archibald has already recruited striker Lyle Taylor on loan from Sheffield United during the January transfer window as he bids to bolster his squad for the second half of the campaign.
A midfielder remains one of his priorities for the club.