A proforma invoice is one of the most misunderstood documents in Nigerian business. Some business owners treat it like a proper invoice; others confuse it with a quotation. Get it wrong and you may send the wrong document at the wrong time - costing you the transaction or creating a compliance headache.
This guide explains exactly what a proforma invoice is, when to use it in Nigeria, and how it differs from a tax invoice under FIRS rules.
What Is a Proforma Invoice?
A proforma invoice is a preliminary document that looks like an invoice but is not a formal demand for payment and carries no legal obligation to pay. It is essentially a confirmed quote - a statement from the seller saying: "Here is what I plan to deliver, and here is what it will cost. Do you agree?"
The word "proforma" comes from Latin, meaning "as a matter of form." It is a document issued in the form of an invoice before the actual transaction takes place.
Key point: A proforma invoice does not record a completed sale. It is not entered into your accounts as income, and your client does not record it as an accounts payable liability.
Proforma Invoice vs Tax Invoice: The Core Differences
| | Proforma Invoice | Tax Invoice | |---|---|---| | When issued | Before the sale / before delivery | After delivery of goods or services | | Purpose | Confirm terms; request approval | Formally request payment | | Creates payment obligation | No | Yes | | VAT applicable | No (not a real sale yet) | Yes (for VAT-registered businesses) | | Recorded in accounts | No | Yes (accounts receivable) | | FIRS compliance required | No | Yes | | Can buyer claim input VAT | No | Yes |
When to Use a Proforma Invoice in Nigeria
1. Before Starting a Project
A Nigerian marketing agency presents a proforma invoice to a new client before work begins. The client reviews the quoted services and prices, approves the document, and pays a deposit - at which point the agency issues a proper tax invoice for the deposit amount.
Example:
Vivid Communications issues Proforma Invoice #PI-2026-003 to Lagos Breweries Ltd:
- Brand campaign strategy: ₦300,000
- Video production (2 × 60-second clips): ₦450,000
- Media buying budget management: ₦120,000
- Estimated Total: ₦870,000
This proforma invoice is for approval purposes only. A tax invoice will be issued upon commencement of services.
Lagos Breweries approves the proforma, pays a 50% deposit (₦435,000), and Vivid raises Tax Invoice #INV-2026-041 for that amount.
2. For Import and Export Documentation
Proforma invoices are widely used in Nigerian import/export to satisfy customs requirements before goods physically cross the border. The Nigerian Customs Service accepts proforma invoices for pre-shipment documentation and Letters of Credit (LC). Once the goods are delivered, a commercial tax invoice replaces the proforma.
3. For Requesting Advance Payments or Deposits
When you need a client to pay upfront before work begins, a proforma invoice formalises the request without creating a completed-sale record. Once the payment arrives, raise a proper tax invoice.
4. When Prices Are Subject to Change
If your prices may vary based on final scope, material costs, or exchange rates, a proforma invoice lets you present indicative pricing without locking both parties into a final obligation.
5. Government and Corporate Procurement
Many Nigerian government ministries, departments, and agencies (MDAs) and large corporates require a proforma invoice during their purchase approval process, before raising a purchase order (LPO). The LPO then triggers the supply, after which you issue a tax invoice.
What to Include on a Proforma Invoice
Because a proforma invoice is not a FIRS-regulated document, there are no statutory mandatory fields. However, include the following to make it useful and professional:
- The words "PROFORMA INVOICE" clearly at the top (this distinguishes it from a tax invoice)
- A proforma reference number (separate series from your tax invoices - e.g. PI-2026-001)
- Issue date and expiry date (proforma quotes should have a validity period - typically 14 to 30 days)
- Your business name, address, and contact details
- Client name and address
- Itemised description of goods or services
- Quantities and estimated unit prices
- Estimated total (in ₦)
- A validity statement: "Prices quoted are valid for 14 days from the date of this proforma invoice"
- A note that VAT will apply on the final tax invoice (if you are VAT-registered)
What to leave out:
- A TIN or VAT registration number is not required (though including your TIN does no harm)
- Do not calculate or show VAT - the sale has not occurred yet
- Do not use a sequential tax invoice number - keep a separate proforma numbering series
Converting a Proforma Invoice to a Tax Invoice
Once the client approves the proforma and work is delivered (or goods dispatched), you issue a proper tax invoice:
- Create a new document with a tax invoice number from your sequential series
- Confirm final prices (update any that changed from the proforma)
- Add your TIN and VAT registration number
- Calculate VAT at 7.5% on taxable items
- Reference the original proforma: "Ref: Proforma Invoice #PI-2026-003"
The proforma becomes a historical document; the tax invoice is the one that matters for payment and FIRS compliance.
Common Proforma Invoice Mistakes
- Calling it an invoice without the "proforma" label - this creates confusion about whether payment is due
- Including VAT on a proforma - VAT is only applicable on a completed supply; adding it to a proforma is premature
- Using tax invoice numbers for proformas - keep the numbering series completely separate
- Not including an expiry date - open-ended proformas create disputes when prices change
Create Both Documents in Minutes
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