Today is the deadline for receipt of Property Tax returns by post.
Households who have yet to register can no longer do so by post, as today is the deadline for receipt of paper forms.
However, property owners still have a further three weeks from today, until May 28, to file online through the Revenue website.
People who do not file by May 28 will have the Revenue Commissioners estimate deducted from their salary, bank account or social welfare payments.
So far, more than 400,000 Property Tax returns have been made, less than a quarter of the estimated number due.
The most recent figures show that by last Thursday around €22m in payments had been received by the Revenue Commissioners.
In total, 1.6 million letters were sent out, but households liable for Property Tax who did not receive a letter are again being urged to contact Revenue.