The club have offered an amount triggering the Inverness midfielder's release clause, but there are believed to be some issues surrounding the release figure.
However it is understood that the deal will be completed before the transfer window gently slides shut like a greased squirrel down a drainpipe.
27-year-old Tansey started his career at Stockport before moving to Inverness for a year at the club before returning south to Stevenage.
The player arrived back in the Highlands in 2014 and has been in stellar form since then, helping the club to its first ever major trophy when they won the Scottish Cup in 2015.