Over 500,000 homeowners have yet to register for the property tax.
Property tax returns must be filed online by midnight tomorrow night.
Some 1.1 million of the 1.6 eligible households in the State have registered so far. Up to the end of April, €22 million in up-front payments had been received.
The Revenue Commissioners are encouraging those who have yet to pay to file as soon as possible by logging on to revenue.ie, where their property ID number and PIN will be required.
Those who do not wish to pay online can file by telephoning 1890 200 255 and transfer the funds by cheque made payable to the Collector General.
People can also pay by cash at any An Post or Payzone outlet or at Omnivend self-service kiosks in locations throughout the country.
Revenue has warned that owners of residential properties who have not received a return form are still liable for the tax.
Meanwhile, nearly two-thirds of homeowners believe the estimated value placed on their property by Revenue is wrong, with most saying that the valuation is too high, according to a survey published this morning.
The AA Home Insurance survey of 2,800 homeowners found that 40 per cent of those asked believed the value of their property had been overestimated, while 15 per cent felt their home had been undervalued, with 42 per cent saying they felt the valuation was correct. Some 13 per cent of those polled said their home had been overvalued by more than one tax band.