Wheater's proposed return to the Barclays Premier League appeared to have stalled at the weekend.
However, the clubs have continued to try to thrash out the financial details for the £2.5million-rated player.
Middlesbrough coach Mark Proctor told the Evening Gazette: "It is ongoing. I do think it is a little bit further forward."
Bolton manager Owen Coyle is keen to bolster his defence after allowing Andy O'Brien to join Leeds.