What to Include on an Invoice in Ireland

7 March 2026

Whether you are a plumber, electrician, carpenter, or any other tradesperson, your invoices need to meet certain requirements in Ireland. Getting this wrong can cause problems during a Revenue audit and makes your business look unprofessional. This guide covers exactly what needs to be on your invoices, with specific guidance for both VAT-registered and non-VAT-registered businesses.

Basic Invoice Requirements (All Businesses)

Every invoice issued by an Irish business, regardless of whether you are VAT-registered, should include the following information:

Your business name — your full name if you are a sole trader, or your registered business name if you trade under a different name
Your business address — the address from which you operate
Contact details — phone number and email address
Customer's name and address — the person or business you are billing
A unique, sequential invoice number — every invoice must have a number, and numbers must follow a sequence without gaps (more on this below)
The date the invoice was issued
A clear description of the goods or services provided — "Plumbing work" is too vague; "Supply and installation of bathroom suite at 12 Main Street, including all pipework and connections" is much better
The total amount due
Payment terms — when payment is due (e.g., "Due within 14 days" or "Due on receipt")
Your bank details — IBAN and BIC for bank transfer payments

These are the essentials. Even if you are not required to charge VAT, having all of this on every invoice protects you legally and makes your business look professional.

Additional Requirements for VAT Invoices

If you are registered for VAT, your invoices must include several additional pieces of information as required by the Value-Added Tax Consolidation Act 2010. On top of everything listed above, a VAT invoice must show:

Your VAT registration number — the IE-prefixed number issued by Revenue (e.g., IE1234567T)
The customer's VAT number — if the customer is VAT-registered and the supply is business-to-business. This is not required for private customers.
The date of supply — the date the goods were delivered or the services were completed, if different from the invoice date
The net amount before VAT — broken down by VAT rate if multiple rates apply
The VAT rate applied — 23%, 13.5%, 9%, or 0% as applicable
The VAT amount — shown separately for each rate
The gross total including VAT

If a single invoice includes items at different VAT rates (for example, standard-rated goods and reduced-rate labour), each rate must be shown separately with its own net amount and VAT amount. The invoice must make it clear which items fall under which rate.

What About Non-VAT-Registered Businesses?

If you are not registered for VAT, your invoices should not show any VAT amount. Do not include a VAT line showing €0.00 or "VAT at 0%". This can confuse customers into thinking you are VAT-registered and charging zero-rate VAT, which is a specific rate reserved for certain supplies like exports. Simply show the total amount due without any reference to VAT.

You should also not include a VAT number on your invoices if you do not have one. If a customer asks for your VAT number and you are not registered, simply explain that you are not VAT-registered and your prices do not include VAT.

The one thing to watch for is the registration threshold. If your turnover is approaching €37,500 (for services) or €75,000 (for goods), keep an eye on your figures. If you exceed the threshold, you must register for VAT and start charging it, even if you are partway through a job.

Sequential Invoice Numbers

This is one area where many sole traders get into trouble. Revenue requires that your invoice numbers are:

Unique — no two invoices can share the same number
Sequential — numbers must follow a logical order (1, 2, 3 or INV-001, INV-002, INV-003)
Without gaps — if you issue invoice 47 followed by invoice 49, Revenue may ask what happened to invoice 48. Missing numbers suggest possible unreported income.

You can use any format you like — plain numbers, a prefix like "INV-" or "WC-", or a year-based system like "2026-001". The important thing is consistency and no gaps.

Invoicing software like Workcanon handles this automatically — each invoice gets the next number in sequence, and you can set a custom prefix. If you are managing numbers manually in a spreadsheet, you need to be careful. It is surprisingly easy to accidentally skip a number or reuse one, especially if you create invoices on different devices or have interruptions.

If you do make a mistake with numbering, do not try to cover it up. Keep a note explaining the gap (for example, "Invoice 48 was created in error and voided") so you have an answer if Revenue asks.

Credit Notes

A credit note is the formal way to correct or cancel an invoice that has already been issued. You should issue a credit note when:

You overcharged a customer and need to reduce the amount
The customer returns goods
You need to cancel an invoice entirely (for example, if the job was cancelled after invoicing)
You agreed a discount after the invoice was sent

A credit note must include:

The word "Credit Note" clearly displayed
A unique, sequential credit note number (separate sequence from invoices)
A reference to the original invoice number and date
The reason for the credit
The amount being credited, including VAT breakdown if applicable
Your business details and the customer's details

Never delete or alter an invoice that has already been sent. If you need to change something, issue a credit note against the original and then issue a new, corrected invoice if needed. This maintains a clean audit trail.

Common Mistakes

Missing invoice numbers or gaps in the sequence. This is the single most common issue Revenue picks up on during audits.
No VAT number on VAT invoices. If you are VAT-registered, your number must appear on every invoice.
Showing VAT when not registered. If you charge VAT without being registered, you are liable for it but cannot file returns. Worse, it is an offence.
Vague descriptions. "Work done" or "Services rendered" is not sufficient. Describe what you actually did, where, and when.
Missing date of supply. For VAT invoices, the date you completed the work matters for determining which VAT period the supply falls into.
Not including payment details. If you want to get paid quickly, make it easy. Include your IBAN, BIC, and any online payment link.
Using the same number twice. This happens more often than you would think, especially when copying previous invoices as templates.

A Simple Checklist

Before sending any invoice, run through this checklist:

Your business name and address are correct
The customer's name and address are correct
The invoice has a unique, sequential number
The date is correct
The description clearly explains the work done
The total is correct
If VAT-registered: VAT number, net amount, VAT rate, VAT amount, and gross total are all shown
If VAT-registered: date of supply is included
Payment terms and bank details are included

Getting your invoices right is not just about compliance — it is about looking professional, getting paid faster, and having clean records when tax time comes around. Set up a good template or use software that handles it for you, and you will never have to think about it again.