Eighteen Days to 19 September: Ireland Bi-Monthly VAT July–August
As of 1 September 2026, Irish bi-monthly VAT traders have eighteen days to file the July–August 2026 VAT 3 by 19 September — plus monthly, four-monthly, and annual VAT packs that share the same date.
Revenue’s Calendar of key dates for tax professionals lists 19 September 2026 for bi-monthly VAT 3 return and payment for July–August 2026, together with the Return of Trading Details where the VAT accounting period ends between 1 July and 31 August. As of Tuesday 1 September, bi-monthly traders have eighteen calendar days to close the twin-month pack.
The same 19 September date also carries monthly VAT 3 for August, four-monthly VAT 3 for May–August, and annual VAT 3 cycles ending in August. Do not assume “bi-monthly only” when your ROS profile still shows a monthly or annual obligation.
Who must diary 19 September
Bi-monthly VAT-registered traders covering July–August 2026, including Return of Trading Details where the VAT accounting period ends between 1 July and 31 August.
Monthly August VAT 3 filers, four-monthly May–August filers, and annual VAT 3 traders whose period ends in August — all share the 19th.
IOSS monthly returns remain a separate track (July IOSS cleared 31 August; August IOSS due 30 September) and do not replace domestic VAT 3.
Eighteen-day prep checklist
Reconcile July and August purchase and sales ledgers this week so VAT 3 boxes are not waiting on open bank matches into mid-September.
Confirm RTD requirements early — missing trading details can block a clean VAT 3 submission even when net VAT looks correct.
Diary September PAYE (14 September return; 23 September ROS payment) beside VAT so mid-month ROS sessions stay sequenced.
Keep December year-end CT1 (23 September) on a parallel track if you carry more than one registration.
How FinnAccountings helps with bi-monthly VAT packs
Organised sales and purchase channels make twin-month VAT packs easier to review. FinnAccountings helps Ireland and UK businesses prepare bookkeeping and VAT packs with Chartered Accountant insight before you or your Chartered Accountant (Ireland) or ICAEW/ACCA adviser files. Start a free trial for review-ready drafts — we prepare records; we do not file VAT 3 or ROS returns on your behalf.
Related reading
Yesterday’s nineteen-day bi-monthly briefing still maps the full September VAT cluster.
August IOSS still has twenty-nine days to 30 September — keep IOSS and domestic VAT diaries separate.
For dual-market VAT estimates while you prep packs, use the free calculator.
Ireland-focused VAT 3 prep guidance sits on the VAT services guide.
Sources & references
This article draws on official guidance and publications from the sources below.
- 1.Calendar of key dates for tax professionals
Revenue (Irish Tax and Customs) · Accessed 2026-09-01
- 2.When VAT becomes payable
Revenue (Irish Tax and Customs) · Accessed 2026-09-01
- 3.How do you complete a VAT 3 return?
Revenue (Irish Tax and Customs) · Accessed 2026-09-01
Put this into practice
FinnAccountings helps with bookkeeping, tax, and VAT prep for Ireland and the UK — with Chartered Accountant insight on AI drafts. Educational articles are not filing advice.
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