The particulars, letter by letter
The list is in Regulation 20(2) of the Value-Added Tax Regulations 2010. Revenue’s page “Information required on a VAT invoice” gives the same list. In order:
| Reg. 20(2) | What the invoice must show |
|---|---|
| (a) | The date of issue |
| (b) | A sequential number, based on one or more series, that identifies the invoice uniquely |
| (c) | Your full name, address and VAT registration number |
| (d) | Your customer’s full name and address |
| (e) | Under the reverse charge: your customer’s VAT number and a statement that the reverse charge applies |
| (f) | For an intra-EU supply of goods: your customer’s VAT number and a statement to that effect |
| (g) | The quantity and nature of the goods, or the extent and nature of the services |
| (h) | The date of supply, or of the payment on account, if it differs from the date of issue |
| (i) | The unit price excluding VAT, any discounts, and the amount excluding VAT |
| (j) | The taxable amount for each rate, and the rate |
| (k) | The VAT payable (except under the reverse charge or a margin scheme) |
| (l) | Your tax representative, where you have one |
Two points cause most mistakes. The number must follow a series without gaps or duplicates, so that each invoice can be identified uniquely; you can run several series, for example one per activity. And the date of supply must appear when it differs from the date of issue, which is often the case for work invoiced at the end of a month.
Reverse charge and EU customers
When the customer accounts for the VAT, under the reverse charge, your invoice shows no VAT amount. Instead it carries your customer’s VAT number and a clear statement that the reverse charge applies (letter (e)). For goods sent to a VAT-registered business in another EU country, letter (f) asks for the customer’s VAT number and a statement that it is an intra-EU supply.
Before relying on a customer’s VAT number, check it in VIES, the European Commission’s system. Revenue’s VIES manual describes Irish VAT numbers as seven digits followed by one or two letters, or, in the older format, six digits and two letters.
VAT in euro, whatever the currency
Regulation 20(8) requires the amount of VAT to be expressed in euro. You can invoice a customer in another currency, but the VAT figure on that invoice must be shown in euro.
The VAT Consolidation Act 2010 also allows simplified invoices for amounts of €100 or less (s. 66(1)(b)) and summary invoices covering a month of supplies (s. 66(1)(c)).
When to issue: the 15-day rule
Under Regulation 23, a VAT invoice must be issued within 15 days of the end of the month in which you made the supply. A supply made on 3 October 2026 must therefore be invoiced by 15 November 2026 at the latest.
- Payment on account: the invoice is due within 15 days of the end of the month in which you received the payment.
- Credit note: the same 15-day logic, counted from when the reduction is agreed (or, for a discount, from when the payment is received).
From a cash point of view, waiting until the deadline is rarely a good idea: payment terms only start once the invoice reaches your customer. Our article on late payment interest in Ireland explains the default 30-day term.
Credit notes
Never alter or delete an invoice once issued. When the price is reduced, a discount is granted or goods are returned, section 67(1)(b) of the VAT Consolidation Act 2010 requires you to issue a credit note, and your customer reduces the VAT it deducted accordingly.
Regulation 20(5) lists what the credit note must show: its date and unique number, the names, addresses and VAT numbers of both parties, the reason for the credit, a reference to the original invoice, and the amount excluding VAT, the rate and the VAT.
Company details: section 151 of the Companies Act 2014
Section 151 of the Companies Act 2014 requires a company to show on its business letters and order forms its name and legal form, its place of registration and the number under which it is registered, and the address of its registered office. The same details must appear on its website, in a prominent and easily accessible place. Failing to do so is a category 4 offence.
The section does not name invoices. The safe option is to print the details on every invoice too:
Example Joinery Limited · Registered in Ireland No. 123456 · Registered office: 1 Example Street, Dublin 2, D02 XY00
Your company number is the one the CRO (Companies Registration Office) gave you. The CRO publishes its register as free open data, which software can use to fill in a company’s name and registered address from its number.
Rates, and businesses that are not VAT registered
Revenue’s current VAT rates include 23% (standard), 13.5% (reduced), 9% (second reduced rate, which since 1 July 2026 also covers hairdressing and restaurant and hot take-away food, excluding alcohol, water and other drinks) and 4.8% (livestock). Each rate is shown with its own taxable amount on the invoice.
The registration thresholds are €42,500 for services and €85,000 for goods. A sole trader below them who has not registered charges no VAT and has no VAT number to show: the invoice still needs a number, a date, both parties’ details, a description and the amount.
PDF by email, and six years of records
Under section 66(2) of the VAT Consolidation Act 2010, an invoice may be issued electronically by prior agreement with your customer. You must then guarantee the authenticity of its origin, the integrity of its content and its legibility, for example through business controls that create a reliable audit trail. A PDF sent by email meets this once your customer has agreed. Structured e-invoices are not compulsory between businesses today: see e-invoicing in Ireland and Revenue’s plan.
Keep invoices and VAT records for six years from the date of the latest transaction they relate to (s. 84). Revenue adds that paper records must stay in the State unless it agrees otherwise.
Frequently asked questions
Does an Irish VAT invoice have to be in English?
Neither section 66 nor Regulation 20 sets a language. The requirement that matters is that the VAT amount is expressed in euro.
Can I invoice in sterling or dollars?
Yes, but the amount of VAT must be shown in euro on the invoice (Regulation 20(8)).
How long do I have to issue a VAT invoice?
Fifteen days from the end of the month in which you made the supply (Regulation 23). The same 15-day rule applies to payments on account and to credit notes.
Must my CRO number appear on my invoices?
Section 151 of the Companies Act 2014 requires it on business letters, order forms and the website, and does not name invoices. Printing it on invoices, with your legal form and registered office, is the safe option.
Is a PDF invoice sent by email valid?
Yes, if your customer has agreed in advance to receive invoices electronically and you can guarantee the invoice’s authenticity, integrity and legibility (s. 66(2) of the VAT Consolidation Act 2010).
Sources
- Irish Statute Book — Value-Added Tax Regulations 2010 (S.I. No. 639 of 2010), Regulations 20 and 23 (irishstatutebook.ie)
- Revenue — Information required on a VAT invoice (revenue.ie)
- Revenue — Other types of VAT invoices (electronic invoices) (revenue.ie)
- Revised Acts — Value-Added Tax Consolidation Act 2010, section 66 (revisedacts.lawreform.ie)
- Revised Acts — Value-Added Tax Consolidation Act 2010, section 67 (credit notes) (revisedacts.lawreform.ie)
- Revised Acts — Value-Added Tax Consolidation Act 2010, section 84 (records) (revisedacts.lawreform.ie)
- Revised Acts — Companies Act 2014, section 151 (revisedacts.lawreform.ie)
- Revenue — Current VAT rates (revenue.ie)
- Revenue — VAT guidance notes on Finance Act 2025 (9% rate from 1 July 2026) (revenue.ie)
- Revenue — VAT thresholds (revenue.ie)
- Revenue — How long should you keep records? (revenue.ie)
- Revenue — VIES Traders Manual (format of Irish VAT numbers) (revenue.ie)
- CRO — Open data: companies (opendata.cro.ie)
This article summarises the official texts to help you get organised. It is not a substitute for personalised advice from your accountant.