Older and Bolder, an alliance of seven member organisations, has been campaigning on a number of issues since 2006.
In particular, Older and Bolder has been pushing for the soon-to-be-produced national positive aging strategy.
More recently, it has resisted the cuts to home care services as part of its campaign for the right to age well at home.
Director Patricia Conboy said the organisation was closing because the grant funding it received from Atlantic Philanthropies was coming to an end.
Atlantic Philanthropies is planning to end grant-making in Ireland by the end of 2016 and has ceased renewing grants.
However, the work of the seven organisations which support Older and Bolder — Active Retirement Ireland; Age & Opportunity; the Alz-heimer Society of Ireland; the Carers’ Association; the Irish Hospice Foundation; the Irish Senior Citizens’ Parliament, and Third Age/Senior Help Line, will continue.
Ms Conboy said the organisation would host an event in April that would bring together individuals and organisations who had been active in their campaigns and identify lessons for the future.
“It will acknowledge the enthusiasm and capacity, among individuals and groups, to continue to speak up and take action to make Ireland a better country to grow older in.”
Older and Bolder began as a short-term campaign group in 2006 but went on to acquire a small number of staff and open an office two years later.
“We are very much appreciative of the support and involvement from older people themselves. We know from the response we are getting that they too appreciated the co-ordinated advocacy voice,” said Ms Conboy.