The time at which residents over 60 and those registered disabled are able to use their free bus pass may rise if cost-cutting measures are approved.
East Sussex County Council said raising the eligibility time from 0900 to 0930 GMT could save up to £160,000 a year.
The county council is taking over the running of the scheme from district and borough councils next April.
It said it anticipated a "significant cut" in the government grant to run the scheme.
A spokesman said the changes may not affect some rural areas where bus services are infrequent.
A consultation into the proposals runs until 20 December. Residents can have their say on the council website or in local libraries.