Ireland ROS September Week Two: PAYE, VAT, CT1 Sequencing
As of 25 August 2026, two working days after the 23 August ROS cash cluster, Irish SMEs should lock September week-two sequencing: August PAYE on 14 September, bi-monthly VAT on 19 September, and CT1/RCT through 23 September — plus July IOSS still due 31 August.
Revenue’s Calendar of key dates for tax professionals sets September’s Irish SME ROS rhythm: PAYE/PRSI/USC/LPT for August on 14 September (payment extended to 23 September for ROS users who file and pay online), a dense VAT 3 cluster on 19 September including July–August bi-monthly returns, and Corporation Tax plus RCT obligations through the 23rd. As of Tuesday 25 August — two working days after the 23 August July PAYE/RCT/CT cash cluster — week-two sequencing should already be on one shared diary.
Treat July IOSS (due 31 August) as a separate month-end track that must not steal the September PAYE and VAT prep slots. Domestic VAT 3 and IOSS never replace each other.
September week-two sequence
14 September — August PAYE monthly return (and DWT/PSWT where due); ROS payment extension to 23 September only if you file and pay online.
19 September — monthly August VAT 3, bi-monthly July–August VAT 3, four-monthly May–August, and annual cycles ending in August, plus Return of Trading Details where required.
1–23 September — CT1 and corporation tax balance for December 2025 year-ends under mandatory e-filing; RCT monthly return for August on 23 September.
30 September — August IOSS monthly return where the scheme applies — diary it now so July’s 31 August close-out does not cascade.
Week-two prep checklist
Lock August payroll runs and employee changes before mid-September leave thins coverage — the 14 September return date arrives faster than it looks.
Reconcile July and August sales and purchase ledgers for the bi-monthly VAT pack while July ROS cash journals are still fresh.
Start iXBRL and Form 46G gathering for December year-end CT1 so validation is not a 22 September surprise.
Confirm ROS digital certificates, payment mandates, and dual approvals for the late-September cash days.
How FinnAccountings helps through September ROS
Organised books make multi-deadline ROS months easier to review. FinnAccountings helps Ireland and UK businesses prepare bookkeeping, payroll, 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
Monday’s September kickoff still maps the post–23 August turn.
August PAYE still has twenty days to the 14 September return.
Bi-monthly July–August VAT shares the same September ROS month.
December year-end CT1 still has twenty-nine days to 23 September.
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 2026-08-25
- 2.Paying tax to Revenue
Revenue (Irish Tax and Customs) · Accessed 2026-08-25
- 3.Corporation Tax (CT) payment and filing
Revenue (Irish Tax and Customs) · Accessed 2026-08-25
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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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