PSV have accepted verbal confirmation that the 21-yearold will put the finishing touches to a move to Wearside in the not too distant future.
And while the Dutch outfit have asked to be kept informed of any hitches that might arise, Sunderland are confident that Mignolet will be providing the back-up to No 1 Craig Gordon next season.
The player's current employers have accepted an offer of a little more than £2m from the Black Cats and the plan is for him to undergo a medical at the Academy of Light.
Mignolet said: Last week I was in Sunderland for talks. I hope I can pass my medical tests and then sign my contract.
The Belgian Under-21 goalkeeper has expressed his wish to move to the Premier League rather than the Eredivisie, despite PSV's willingness to match Sunderland's proposal.
But Belgium's St-Truidense, where he has played since the age of 16, are expecting a deal to be done with Sunderland.
St-Truidense general director Guy Mangelschots said: PSV understand that Simon would prefer a move to England.
If the deal with Sunderland breaks down they would still be interested. We now expect things to move quickly.
Once the transfer is completed, Bruce will have made his second signing of the summer.
Mignolet will follow Paraguayan midfielder Cristian Riveros, who is playing for his country in the World Cup, to the North-East.
Sunderland forward Daryl Murphy is emerging as one of the most likely candidates to be first out of the door in the other direction.
Murphy is still wanted by Roy Keane at Ipswich Town, where he was a hit in the Championship on loan at the end of last season.
But Murphy has learned of interest from both Celtic and Rangers, two clubs he is likely to accept substantial pay cuts to move to this summer.
The Republic of Ireland international was aware of interest from Celtic, but a delay in the announcement of Neil Lennon as the new Bhoys boss has slowed transfer movement down in the last two weeks at Parkhead.
But there is an expectation in Glasgow that Lennon will step up his recruitment drive after yesterday's confirmation that Alan Thompson is heading back to Celtic to join the backroom staff.
The pending arrival of Thompson, who has left his role as Newcastle's reserve team boss, is an indication that a managerial announcement is not too far away, meaning Lennon will then look to sign new players, with Murphy high on his list.
Bruce is keen to offload a striker who is unlikely to form part of the restricted 25-man squad the FA's new rules will demand next season.