Mature students at a university have launched a campaign after deeming a bus company "ageist" for saying they are too old for a discounted bus pass.
The group from Plymouth University are waging war on Citybus who insist those eligible for its concessionary fares have to be under 23, regardless of whether they are still in full-time education.
The students say they feel "discriminated" at the policy, which favours younger students.
Vice president of the university's Student Union (PUSU) education and welfare office Emma Wilson said a number of students approached her at the beginning of the academic year complaining they had been refused the student fares.
After contacting Citybus, Wilson says she received a "less than satisfactory reply" and the policy remained unchanged.
"Now more and more students are angered by the policy and so we have started a campaign to get things changed - we are appealing to any students in the city who feel discriminated to join us."
Commercial manager of Plymouth Citybus, Peter Oliver, said the company was one of the few to offer student discount.
"There is a limit to the discount we can offer. If we open it up to a wider range of people then the value of it diminishes," he told the Huffington Post UK.
"Because the concessionary fares are done on smart card and key, there is no database that we can access that tells us who is in full time education. It is difficult to differentiate between those in full time and those in part time.
"It's only recently that we opened child fares from 16 years of age to include those up to 19 years of age and students to those under 23."
Oliver added he did not feel the scheme was discriminatory nor ageist.
But bus services in other university towns offer mature students the same discount as their younger peers. The bus pass at Leeds Metropolitan University and the Metro bus service in Yorkshire offer a concessionary ticket to students regardless of age.
Plymouth City Council declined to comment on the issue.
NUS vice president of welfare, Pete Mercer described the discretionary student travel concession schemes as a "postcode lottery" across the country.
"Many students who need support in order to access education do not receive it, and for no good reason.
"Arbitrary age restrictions fail to take account of the changing demographic profile of students and the huge financial pressures faced by those in full-time education, whatever their year of birth."
Mercer added there was "simply no excuse".
"Bus operators need to learn from existing schemes in operation elsewhere to urgently enter into a dialogue with local colleges and universities to ensure full-time student status can be confirmed."