After 23 August ROS: Ireland’s September Deadline Kickoff
As of 24 August 2026, Ireland’s July PAYE (ROS extension), July RCT, and November-year CT cash cluster has cleared — turn immediately to September: PAYE 14th, bi-monthly VAT 19th, CT1/RCT through the 23rd, and July IOSS still due 31 August.
Revenue’s Calendar of key dates for tax professionals listed 23 August 2026 for the electronic PAYE/PRSI/USC/LPT payment window for July (where the ROS extension applied), July Relevant Contracts Tax, and Corporation Tax returns and balances for accounting periods ending in November 2025. As of Monday 24 August, that ROS cash cluster is behind you — the next risk is treating August close as finished work instead of the start of September’s denser month.
September 2026 stacks PAYE/DWT/PSWT for August on 14 September (payment extended to 23 September for ROS users who file and pay online), a multi-frequency VAT 3 cluster on 19 September (including July–August bi-monthly), Corporation Tax and RCT windows through 23 September, and August IOSS on 30 September. July IOSS still sits on 31 August — seven days from today.
What to lock this week after the 23 August cluster
Reconcile any late July payroll journals and RCT deductions that cleared yesterday so August PAYE and August RCT packs start from a clean base.
Confirm ROS digital certificates and bank mandates remain live before mid-September holidays thin coverage — do not discover an expired cert on 14 or 19 September.
Open the December year-end CT1 / iXBRL / Form 46G workstream now: Revenue’s nine-month rule still points calendar-year companies at 23 September for the return and any balance.
Keep July IOSS (31 August) on a separate diary from domestic VAT 3 — IOSS does not replace Irish VAT obligations.
September ROS sequencing checklist
Diary 14 September for August PAYE/PRSI/USC/LPT, DWT, and PSWT — and the 23 September ROS payment extension only if you both file and pay online.
Build the July–August bi-monthly VAT 3 (plus monthly, four-monthly, and annual packs that share 19 September) while August sales invoices are still fresh.
Sequence CT1 December year-ends and August RCT toward the 23 September electronic window alongside October AP preliminary tax where it applies.
If yesterday’s ROS payment failed or was incomplete, contact Revenue promptly — interest runs on late or underpaid amounts even when the calendar date has passed.
How FinnAccountings helps into September
Clean August close shortens every September ROS pack. FinnAccountings helps Ireland and UK businesses prepare bookkeeping and tax 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 ROS returns or make Revenue payments on your behalf.
Related reading
Yesterday’s due-today briefing still maps the statutory cluster that just closed.
July IOSS still has seven days — do not let September prep crowd it out.
CT1 for December year-ends now has thirty days on the midday diary — start iXBRL now.
August PAYE for September’s 14th now has twenty-one days — lock payroll after yesterday’s cash cluster.
Sources & references
This article draws on official guidance from the sources below.
- Calendar of key dates for tax professionals
Revenue (Irish Tax and Customs) · Accessed 2026-08-24 - PAYE Modernisation — employers
Revenue (Irish Tax and Customs) · Accessed 2026-08-24 - Corporation Tax (CT) payment and filing
Revenue (Irish Tax and Customs) · Accessed 2026-08-24
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