AI agents for business finance: what they can and can't do
What AI agents can do in bookkeeping, close, collections and compliance today, where a person must stay in charge, and how to judge a product.
The short answer
Keep a full tax invoice from the Nigerian supplier (its Tax ID, registration number, invoice number, date, your name, the amount and any VAT), the bank record that shows the payment left your account, and proof of what was delivered. If tax was withheld in Nigeria, keep the withholding receipt the payer issued. Link the three together per transaction so a reviewer can follow invoice, payment and delivery without asking you.
A South African business that buys from Nigeria usually has the payment record in perfect order and the paperwork behind it in a WhatsApp thread. When SARS, an auditor or your own bank asks what a R60,000 transfer to Lagos was for, a screenshot of a chat is a weak answer. This guide sets out what a strong supporting document from a Nigerian supplier looks like, what Nigerian law says that document should contain, and how to keep a trail that does not depend on anyone's memory.
The question every reviewer is asking
Whatever form the request takes, a reviewer wants four things answered for each payment: that it happened, who received it, what it bought, and that the purchase was for the business. One document rarely answers all four. A complete record for a supplier payment usually has three parts:
- The supplier's invoice, issued before or at the time of payment, naming your business as the buyer.
- Proof of payment from your bank: the outgoing payment confirmation or statement line, with the reference you used.
- Proof of delivery or performance: a delivery note, shipping document, signed acceptance, or for services a report or deliverable with a date.
When payments abroad go through a South African bank, the bank acts as an authorised dealer under the Reserve Bank's Currency and Exchanges Manual, and it may ask for the invoice before it releases the funds. Keeping the invoice ready for the bank and keeping it for SARS are the same job.
What Nigerian law says a supplier's invoice should show
Nigeria's VAT rules under the Nigeria Tax Act 2025 set out what a VAT invoice must contain. According to a May 2026 review of the Act's VAT provisions, section 153 requires:
- the supplier's Tax ID (TIN) and its incorporation or registration number;
- an invoice number;
- the supplier's name and address;
- the date of supply;
- the purchaser's name;
- the gross amount, the VAT charged and the rate.
That list is a useful test even when the supplier is a small trader that is not charging VAT. An invoice without a registration number, a date or your business name is the first thing to send back. Ask once, at onboarding, and save the supplier's CAC certificate or business name registration and Tax ID in your supplier file so you are not chasing them later. For what a good Nigerian business receipt contains in more detail, see what a business receipt in Nigeria should include.
When tax was withheld on the Nigerian side
If your South African company sells to Nigeria as well as buying from it, the documents flow the other way too. Under Nigeria's 2024 deduction-at-source regulations, the Nigerian customer that deducts withholding tax issues a receipt showing your name, address and TIN, the nature of the transaction, the gross amount, the tax deducted and the month. Keep every one: SARS's Interpretation Note 18 makes documentary proof of foreign tax a condition of any foreign tax relief, with extra information needed where tax was withheld at source.
Building the audit trail
The aim is that anyone opening your records can move from a bank line to the invoice to the delivery evidence in under a minute. A simple structure works:
| Field | What to record | Why |
|---|---|---|
| Supplier ID | One code per supplier, linked to its CAC and TIN copies | Stops duplicate supplier records |
| Invoice reference | Supplier's own invoice number | Matches what the supplier will quote |
| Payment reference | The reference you put on the transfer | Matches the bank statement line |
| Currency and amounts | Invoice currency, amount paid, rand cost | Explains exchange differences |
| Delivery evidence | File name of delivery note or deliverable | Proves the purchase happened |
| Approver | Who approved the payment and when | Shows control over spending |
Put the supplier's invoice number in your payment reference wherever the bank allows it. That one habit closes most of the gaps reviewers find.
How long to keep it
Nigeria's Tax Administration Act 2025 (section 31) requires books and records sufficient to work out tax liability, kept in English for not less than six years after the year of assessment, with a certified translation on demand. Your South African records have their own retention rules; keep each record for whichever period is longer. Our guide to SARS record keeping for businesses covers the South African side.
Common weak documents and how to fix them
- Proforma invoice only. Ask for the final invoice after delivery; a proforma is a quote.
- Invoice addressed to you personally. If the company paid, the invoice should name the company.
- Chat screenshot as proof of payment. Replace it with the bank's own confirmation or a statement line.
- Supplier paid through a third party's account. Get a written instruction from the supplier naming that account before paying, and keep it with the invoice. Our checklist on verifying a Nigerian supplier before paying covers this.
- Altered or re-sent PDFs. If two versions of an invoice exist, keep both and note which one you paid.
Where Pryme fits
A Pryme Business Account holds NGN, USD, GBP and EUR with local account details for each (business multicurrency), so naira payments to suppliers sit on one statement. Any customer can generate a regular or a verifiable receipt or statement through Pryme's partnership with VerifyDoc.ai, and anyone you send a verifiable one to can check it is genuine and unaltered (verifiable receipts). Outside Nigeria, Pryme's activities are carried out through regulated partners.
Questions people ask
Will SARS accept an invoice from a Nigerian supplier in naira?
Currency is not the issue; completeness is. Keep the full invoice, your bank record of the payment in rand, and delivery evidence, and record the rand cost you actually paid.
What should a Nigerian VAT invoice show?
Under the Nigeria Tax Act 2025 (s.153, as summarised in May 2026): supplier TIN and registration number, invoice number, supplier name and address, date of supply, purchaser name, gross amount, VAT charged and rate.
Is a WhatsApp chat enough proof of a supplier payment?
No. Use it to find the facts, then keep the supplier's invoice, the bank's payment confirmation and delivery evidence as the record.
How long should we keep Nigerian supplier records?
Nigeria's Tax Administration Act 2025 sets at least six years after the year of assessment. Keep each record for the longer of the Nigerian and South African periods.
Sources
- Mondaq, Examination of the value added tax provisions under the Nigeria Tax Act 2025 (28 May 2026) · accessed Oct 2026
- Mondaq, An overview of the Nigerian withholding tax regulations of 2024 · accessed Oct 2026
- Nigeria Tax Administration Act 2025 (gazetted text) · accessed Oct 2026
- SARS, Interpretation Note 18 (Issue 5, 9 December 2022): Rebate and deduction for foreign taxes on income · accessed Oct 2026
- South African Reserve Bank, Currency and Exchanges Manual for Authorised Dealers (version 1.1.36, 8 October 2026) · accessed Oct 2026
This article is general information, not financial, legal or tax advice. Products described are provided under the terms on this site and are subject to regulation and eligibility.