The rhythm: bi-monthly, due on the 19th (23rd through ROS)
The default taxable period is two months, starting on 1 January, March, May, July, September and November. The return and payment are due by the 19th of the month after the period ends. For ROS filers Revenue extends that to the 23rd, and since every registered business must file and pay electronically, the 23rd is the date that matters in practice. Late filing or payment can attract interest and penalties.
VAT3 due dates for 2026
| Taxable period | Statutory due date | ROS due date |
|---|---|---|
| January to February 2026 | 19 March 2026 | 23 March 2026 |
| March to April 2026 | 19 May 2026 | 23 May 2026 |
| May to June 2026 | 19 July 2026 | 23 July 2026 |
| July to August 2026 | 19 September 2026 | 23 September 2026 |
| September to October 2026 | 19 November 2026 | 23 November 2026 |
| November to December 2026 | 19 January 2027 | 23 January 2027 |
Not everyone is on the two-month cycle. The Collector-General may put you on four-monthly returns if your annual VAT liability is between €3,001 and €14,400, or six-monthly returns if it is between €1 and €3,000. Businesses that are constantly in a repayment position can ask Revenue for monthly returns.
The four boxes that matter
| Box | What goes in it (Revenue wording, shortened) |
|---|---|
| T1 | VAT on sales: total VAT due on your supplies, intra-EU acquisitions of goods, imports under postponed accounting and received services |
| T2 | VAT on purchases: total VAT you are entitled to reclaim on costs relating to your taxable supplies, plus the flat-rate addition paid to farmers |
| T3 | VAT payable: T1 minus T2, when T1 is bigger |
| T4 | VAT repayable to you: T2 minus T1, when T2 is bigger |
The trade boxes are totals of value, not VAT: E1 goods sent to other EU countries, E2 goods received from them, ES1 services supplied to EU customers, ES2 services received from EU suppliers, and PA1 the customs value plus duty of goods imported under postponed accounting. For a purely domestic trader they are all zero. Credit notes issued or received adjust T1 and T2.
Where the calculator earns its keep
Building T1 and T2 means extracting the VAT from a pile of gross receipts, and that is where people subtract 23% instead of dividing by 1.23 and quietly overstate their reclaim. Run each gross amount through the remove-VAT mode: it divides correctly for every Irish rate, including 13.5% repair receipts and 9% electricity, gas and restaurant bills.
Repayments
When T2 beats T1, Revenue repays the T4 amount directly to your bank account. The Collector-General can withhold the repayment if you have any outstanding tax returns, and can offset it against other tax you owe. Keep the rest of your filings clean if you are expecting money back.
The RTD: the return everyone forgets
Once a year, alongside your normal cycle, Revenue expects the Return of Trading Details, an annual breakdown of purchases and sales by VAT rate. It appears in your ROS inbox at the end of the year. No payment attaches to it, so it feels optional. It is not: an outstanding return of any kind lets the Collector-General hold your VAT repayments. It is ten minutes in ROS if your bookkeeping is clean.
Three mistakes Revenue actually notices
- Reclaiming VAT that was never reclaimable. T2 only covers costs that relate to your taxable supplies. Entertainment, most food and drink, and passenger cars (with narrow exceptions) do not qualify, no matter what the receipt says.
- Missing nil returns. Quiet period, no return filed, automatic reminder letter, then estimates. Revenue’s instruction is explicit: return the period with 0 in T1 to T4, and never write “nil” in a box.
- Round-number returns. T1 and T2 ending in suspiciously many zeros, period after period, invites a closer look. Real books produce ragged numbers.
Frequently asked questions
When is the VAT3 return due?
The return and payment are due by the 19th of the month after the taxable period ends. If you file and pay through ROS, which registered businesses must, Revenue extends that to the 23rd. For bi-monthly filers the ROS dates are 23 March 2026, 23 May 2026, 23 July 2026, 23 September 2026, 23 November 2026, 23 January 2027.
What are T1, T2, T3 and T4 on the VAT3?
T1 is the VAT due on your sales, intra-EU acquisitions, postponed-accounting imports and received services. T2 is the VAT you are entitled to reclaim on costs that relate to your taxable supplies. T3 is VAT payable (T1 minus T2 when T1 is bigger). T4 is VAT repayable to you (T2 minus T1 when T2 is bigger).
How often do I file a VAT return in Ireland?
The default is every two months: periods start on 1 January, March, May, July, September and November. The Collector-General may allow four-monthly returns if your annual VAT liability is between €3,001 and €14,400, and six-monthly returns if it is between €1 and €3,000. Businesses usually in a repayment position can ask for monthly returns.
What is the RTD?
The Return of Trading Details is an annual form that lists your total purchases and sales for the year broken down by VAT rate. Revenue puts it in your ROS inbox at the end of the year. No payment attaches to it, but the Collector-General can withhold repayments while any return is outstanding.
Do I file a VAT3 if I had no sales?
Yes. Revenue says a period with nothing payable or repayable must still be returned with zero at T1, T2, T3 and T4. Do not type the word "nil" in any box; enter 0.