Government, Transport Scotland and the bus industry have signed up to new fare reimbursement arrangements which include a phased reduction in the reimbursement rate over the next two years.
Bus operators receive money from the Government to cover the costs of its concessionary travel policy.
The new deal ensures that bus firms receive all of this year's budget and a further £10 million to help their cashflow, and arrangements have also been made to help them with the reduction in reimbursement rate.
Currently the concession rate is 67% of an adult fare. This will be reduced to 60% in 2013/14 and then 58.1% in 2014/15.
Transport Minister Keith Brown said: "Concessionary travel is a key part of the Scottish Government's social wage and makes a real difference to many of our elderly and disabled.
"Our track record in funding bus travel speaks for itself. We are continuing to provide £250 million annually to the industry, investing not just in concessionary travel but support for services and new green buses.
"The changes to the reimbursement arrangements are based on hard evidence and we have worked with the industry to provide them with some much-needed stability going forward.
"But the needs of the passenger must come first and we are encouraging operators to continue to work with us to deliver services for passengers at affordable prices."