Drivers employed by First Hampshire and Dorset have rejected the company's latest pay offer and will go on strike for 24 hours on Monday 10th February.
Around 60 drivers, who are members of Unite, rejected the offer as "there were too many strings attached, which would have meant a reduction to their terms and conditions".
Monday's strike will start at 4:30 and run for 24 hours.
Passengers in the Bridport, Portland and Weymouth area will be affected.
Unite regional officer Bob Lanning said, "The crux of this dispute is that our members are lagging behind the pay of their counterparts working for other regional bus operators, at a time when household bills are going through the roof."
Talks to solve the pay dispute involving about 60 drivers at First Hampshire and Dorset, and Unite, will be continuing next week.
As a result, Unite has suspended the 24 hour strike due for Wednesday to allow for the talks.
However, if the dispute is not settled by the end of next week, Unite has already given the company notice that there will be a 24 hour strike on Monday 3rd February that will hit the Bridport, Portland and Weymouth areas.
The management offered 1.5% for April 2013 - April 2014 which would take the pay to £8.50 an hour – however, the company wanted to claw back that rise by eroding terms and conditions, such as reduced sick pay, so the deal was self-financing.