Mortgage holders are being told they could save hundreds of euro a year.
A new campaign from the Competition and Consumer Protection Commission (CCPC) is urging both existing mortgage holders and first time buyers to ensure they are getting the best value.
It says customers should "not to be distracted by the lure of cash", and should instead focus on potential long-term savings.
It comes as AIB is dropping its variable rates by 0.25% - that means annual savings of over €300 on a €200,000 mortgage.
The change is expected to put pressure on other lenders to follow suit.
But the CCPC is still advising people to be cautious.
Their spokeswoman is Aine Carroll, and she says people could save tens of thousands of euro over the course of a mortgage when they check all the options available.