The Department for Infrastructure is considering increasing the age of eligibility for free public transport in Northern Ireland.
The 12-week public consultation will review eligibility for the scheme, which has not changed since 2008.
One of the changes being considered is raising the age of concessionary fairs to 65, or the state pension age.
The Commissioner for Older People for Northern Ireland has said he is "hugely concerned" about the "short-sighted" proposals.
The current set-up allows older people (60+) and some disabled people to travel for free or at a discounted rate using a SmartPass.
The change would apply to new and current users and would bring Northern Ireland in line with England and the Republic.
The Department is, however, also consulting on extending eligibility to include free travel for disabled people who currently qualify for a half-fare SmartPass, as well as a companion pass for disabled people who qualify for a pass and are unable to travel alone.
The cost of the scheme has risen significantly since 2010/11.
There have been a number of reasons for this including increased fairs and rising numbers of people who are eligible for the scheme. In 2022/23 the scheme cost the Department for Infrastructure (DfI) £39m with estimates for 2023/24 topping £44.6m.
Department estimations indicate the cost of the scheme could further increase to more than £52m by 2030.
Eddie Lynch, the Commissioner for Older People for Northern Ireland, said the SmartPass is a "lifeline" and "an essential means of transport" for thousands older people in the 60-64 age bracket.
He said: "Without it, I fear that many older people’s mobility and health and well-being will be adversely affected, at a time when they are not only struggling with the cost-of-living crisis, but perhaps also just recently re-integrating back into society following the pandemic.
"Stripping them of an essential means of transport to attend GP appointments, hospital appointments, attend day activities, visiting friends & family, post office / banking services and links to the public transport network not only negatively impacts on their mental health but takes away their independence causing them to rely more heavily on friends and family," he added.
In a statement a DfI spokesperson said: “We recognise the importance of the scheme and the benefits it brings to those who use their SmartPass to travel on public transport.
"However, the cost of the scheme has increased significantly and we anticipate it will continue to rise.
"With that in mind we are looking at all options to ensure the scheme will continue to promote social inclusion, without impacting the delivery of public transport services or other services the department provides. “No decisions have been made yet. We are keen to hear from the public, representative groups and others on how the proposed changes might affect them.
"We also want to hear view on how the scheme might operate in the future. Our priority is to ensure that it is affordable and at the same time, targeted at those who need it most.”
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