Tax experts say the window to claim is closing
People paying for nursing homes, home carers, or medical expenses for incapacitated children are being urged to apply for tax credit.
Taxback.com say that millions is being left unclaimed in tax refunds.
It says up to one-third of eligible taxpayers appear unaware that there is still "sizeable tax relief" with these costs.
Eileen Devereux is commercial director at Taxback.com: "We are flagging this issue because we believe many people are unaware they are eligible for a tax rebate on 'carer' expenses incurred on a regular basis.
"These rebates could go a long way to alleviating at least some of the financial burden people are under.
"For example nursing home fees is an area which has evaded the slashing of tax reliefs in recent years, with the relief still allowable at the higher rate of tax if applicable - 40%."
Recent reports have suggested that the average cost of private sector nursing homes, which house 75% of the 30,000 people in nursing homes in the country, is €1000 per week - with some costing as much as €2,000.
Similar relief is also open to those employing home carers and those looking after incapacitated children.
According to most recent figures from the Revenue Commissioners, just 1,910 people claimed the ''Person Employed to take care of an Incapacitated Individual'' tax credit in 2014.
"Our experience suggests that this figure is relatively low considering a number of homecare agencies have more clients on their books than this", Devereux added.
Similarly, 20,300 people claimed the 'Incapacitated Child tax Credit' credit for the same year. However, in the 2011 Census more than 106,000 families indicated they care for a child with a disability.
Devereux says: "While not all of these families may not qualify for the tax credit, we are confident that the number could be higher than the current 20% currently claiming it."
Families who employ home carers to look after their relatives or children typically pay up to €1,800 for a five-day working week to one of the 150 private homecare companies.
Relief is available to those employing a home carer by taking a deduction from your taxable income, rather than by tax credit.
"The entitlement to claim a refund becomes null and void if the costs were incurred more than four years ago, so it's imperative that people act in time", Devereux adds.