Revenue is writing to about 130,000 taxpayers who have not claimed any additional tax credits or reliefs in the last five years to remind them that there is a four-year time limit for the process.
Revenue has issued the letters over the last few years to assist taxpayers in claiming their due entitlements and ensuring they only pay the correct amount of tax.
It said an analysis of a previous campaign suggests that the letters have a significant positive effect on taxpayer engagement with it.
Pat Murphy, national PAYE manager in Revenue's Personal Division, said: "You can claim a refund of tax paid if there are entitlements you are due but have yet to claim.
“However, there is a four-year time limit for claiming tax refunds and the deadline for 2015 claims is December 31st, so now is a good time to check that you have claimed all of your entitlements.
‘Convenient’
“For taxpayers who want to make a claim, the quickest, easiest and most convenient way to do so is online using PAYE Services, which is available in Revenue’s myAccount portal.
“You can register for, or sign in to, myAccount on the Revenue website at www.revenue.ie. The services in myAccount are accessible on all mobile devices.”
Mr Murphy added: “Even if you did not get a letter from Revenue, you can review and update your tax record online at any time, using PAYE Services in myAccount.
“When you submit a claim, it is processed and verified by Revenue, and most online refund claims are paid within five working days. So there is still plenty of time to submit your claim and have your refund paid into your bank account before Christmas.”
