Showing your Nigeria Tax ID on invoices and returns
Where a Nigerian business must show its 13-digit Tax ID, how it gets its own and its customers' numbers onto Achekam documents, and a PDF defect to watch.
By Achekam · · 4 min read · For Running a business businesses in Nigeria
Open the invoice template your business has used for years and look at the footer. If it still shows an old TIN, it is out of date. Since 1 January 2026, Nigeria has issued a 13-digit Tax ID that replaces previously issued TINs, and the law expects that number on your returns and on the documents you issue for your transactions.
Changing a number in a footer sounds trivial. In practice it raises several questions: where exactly the number must appear, how to find your own, what your invoicing system does with it, and how your customers' numbers print. This article answers them for a business invoicing from Achekam.
Every taxable person needs one
Every taxable person in Nigeria must obtain a Tax ID and show it on returns and transaction documents, under sections 6 to 8 of the Nigeria Tax Administration Act 2025. Transaction documents are the paperwork of trade, and your invoices are the obvious example.
For a business, two numbers matter on an invoice: your own, so the customer and the tax system know who sold, and, where you have it, your customer's, so the sale is tied to the buyer.
Retrieving a company's Tax ID with its CAC number
The Tax ID is issued through two portals, taxid.jrb.gov.ng and taxid.nrs.gov.ng. A company retrieves its Tax ID with its CAC registration number; an individual uses their 11-digit NIN, name and date of birth. The NRS explains how to get or retrieve a Tax ID from the national portal, using a NIN for individuals or a CAC registration number for businesses, and why the Tax ID should be validated.
When you retrieve it, save the result showing the company name, the number and the date. That record is your evidence that the number on your invoices is the one the authority issued.
Your own number on your documents
In Achekam, a business enters its VAT registration number in Settings, under Firm Profile. Documents made by Achekam's server print that number, and they are titled "Tax Invoice" only when a VAT number is set.
That rule works in your favour if you are a small business. A small business in Nigeria is exempt from registering for, charging and filing VAT, unless it opts in. If you are not VAT-registered, leave the VAT number empty, and server-made documents will not call themselves tax invoices. If you are VAT-registered, ask your adviser which number your VAT registration now sits under, since the Tax ID replaced the old TINs, and enter exactly that. Where you stand on the exemption is covered in the small business VAT exemption.
Check one point on your workspace too. A workspace registered as Nigerian at sign-up makes the Nigeria pack its default and, when the pack is activated, sets the naira and the Africa/Lagos time zone unless they were already set. If your workspace shows the wrong currency or time zone, that is the setting to look at.
A PDF defect to watch for
There is a known problem with one kind of document. The invoice PDF downloaded or e-mailed from the invoice screen is always headed "TAX INVOICE" and cites the South African VAT Act, whatever the business's country or VAT number. This is a defect in the PDF made in the browser; the server's own template handles the heading correctly.
Until it is fixed, open every invoice PDF before it goes to a customer. A Nigerian invoice that names the South African VAT Act, or calls itself a tax invoice when you are not VAT-registered, is the wrong document to send.
How a customer's Tax ID prints
On Achekam's documents, a customer's tax number prints as a VAT number only when it looks like a South African VAT number, and otherwise as a tax number. A Nigerian customer's 13-digit Tax ID therefore prints labelled as a tax number, which is accurate.
Collect the customer's Tax ID when you open their account, not when the first invoice is due. A large customer's accounts department may reject an invoice that lacks the details it needs, and chasing a number after the fact delays payment.
What Achekam checks, and what it cannot
Achekam checks only that a Nigeria Tax ID has 13 digits. It cannot confirm a Tax ID with the authority, because no public verification service was found. It will not accept a NIN in place of a Tax ID, and it stores CAC numbers as digits without checking their length. A number that passes the length check can still be wrong, so the portal look-up and the saved evidence remain your proof. The checks, and their limits, are set out side by side for Nigeria and Kenya in Nigeria Tax ID and KRA PIN: what is checked.
A Tax ID checklist for invoicing
- Retrieve your company's Tax ID on the portal with its CAC number, and save the evidence.
- Remove any old TIN from templates, letterheads and e-mail signatures.
- Decide with your adviser what goes in the VAT number field in Firm Profile, or leave it empty if you are not VAT-registered.
- Collect each customer's Tax ID when you open their account, and keep the evidence of where it came from.
- Open each invoice PDF before sending it, watching for the South African heading defect.
- Use the Tax ID on every return you file.
A footer is a small thing. Getting it right is the first step in invoices that the tax system, and your customers' accounts teams, can match to you without a query.
General guidance only, not advice on your own circumstances. Tax and payroll rules change: check the current position with the authority or your adviser.
