Many Nigerian business owners are familiar with invoices and receipts, but debit notes remain poorly understood — even though they are a standard tool in B2B accounting. Knowing when and how to use a debit note can save you from invoice disputes, keep your VAT records accurate, and maintain professional relationships with clients and suppliers.
What Is a Debit Note?
A debit note is a document issued by a buyer to a seller (or by a seller to a buyer in specific circumstances) to formally request an adjustment that increases the amount owed.
The most common use: a buyer issues a debit note to a seller when the seller has undercharged, when goods were returned to a supplier and a refund is owed, or when there is a price discrepancy between the purchase order and the invoice received.
Conversely, a seller can issue a debit note as an alternative to raising a supplementary invoice — for example, to charge for additional work not included in the original invoice.
Debit Note vs Credit Note vs Invoice
These three documents are closely related. Here is how they differ:
| Document | Issued by | Effect on balance | Common use | |---|---|---|---| | Invoice | Seller | Increases amount buyer owes | Billing for goods or services | | Credit note | Seller | Reduces amount buyer owes | Overcharge, return, cancellation | | Debit note | Buyer or Seller | Increases amount owed | Undercharge correction, price dispute, returns to supplier |
Think of a debit note as the buyer's equivalent of the seller's invoice — it formally records that an additional amount is owed or a credit is due from the supplier.
Common Situations Requiring a Debit Note in Nigeria
1. Undercharge on a Supplier Invoice
You receive an invoice from your supplier for ₦150,000, but the agreed price was ₦175,000. Rather than asking the supplier to reissue the invoice, you issue a debit note for the ₦25,000 difference, formally notifying the supplier to charge you the correct amount.
2. Returning Goods to a Supplier
You return ₦40,000 worth of defective goods to your Lagos supplier. You issue a debit note for ₦40,000 (plus VAT adjustment) to inform the supplier that they owe you this credit.
3. Price Variation on a Construction Contract
A contractor completes additional work not covered in the original contract. Rather than issuing a new invoice, the contractor issues a debit note to document the variation and request payment for the extra work.
4. Inter-Company Charges
Within a group of related companies, debit notes are commonly used to allocate shared costs — e.g., a parent company issues a debit note to a subsidiary for management fees or shared IT costs.
What a Nigerian Debit Note Must Include
A compliant debit note should contain:
- The words "DEBIT NOTE" — clearly at the top of the document
- Your business name, address, and TIN
- Recipient's business name, address, and TIN
- Debit note number — unique and sequential (e.g., DN-2026-004)
- Date of issue
- Reference to the original invoice or purchase order — e.g., "Re: Invoice INV-2026-031 dated 1 February 2026"
- Reason for the debit note — clear and specific
- Itemised amounts — what is being charged and why
- VAT adjustment — if the underlying transaction attracts VAT
Debit Note Example — Nigeria
Situation: Emeka Supplies Ltd received Invoice INV-2026-031 from Eze Traders for ₦200,000 + VAT. The agreed contract price was ₦230,000 + VAT. Emeka Supplies issues a debit note to Eze Traders for the ₦30,000 shortfall.
DEBIT NOTE Emeka Supplies Ltd 22 Industrial Avenue, Apapa, Lagos | TIN: 9876543-0001
Debit Note No: DN-2026-004 Date: 15 March 2026 Re: Invoice INV-2026-031 from Eze Traders, dated 1 February 2026
To: Eze Traders Ltd Plot 7 Trans-Amadi, Port Harcourt TIN: 1122334-0002
Reason: Undercharge on Invoice INV-2026-031. Agreed contract price per LPO No. PH-2026-009 was ₦230,000. Invoice received was ₦200,000.
| Description | Amount | |---|---| | Price shortfall — Invoice INV-2026-031 | ₦30,000 | | VAT (7.5%) | ₦2,250 | | Total amount due | ₦32,250 |
Please issue a revised invoice or supplementary invoice for ₦32,250 at your earliest convenience.
VAT on Debit Notes in Nigeria
When a debit note relates to a VATable transaction, the VAT adjustment must be included. FIRS requires that VAT records (both output VAT for the seller and input VAT for the buyer) reflect the debit note adjustment.
The seller receiving the debit note should:
- Issue a supplementary invoice or confirm the additional amount
- Declare the additional output VAT in their next monthly VAT return
The buyer issuing the debit note should:
- Retain the debit note as documentation for an increased input VAT claim (once the supplier confirms)
Debit Note Numbering
Use a separate sequential series for debit notes — distinct from your invoices and credit notes. A common prefix is DN- (e.g., DN-2026-001).
Create FIRS-Compliant Invoices and Documents
InvoiceGenerator.ng helps Nigerian businesses create professional invoices for services and goods — with automatic VAT, sequential numbering, and WhatsApp delivery. For a full overview of Nigerian invoicing requirements, see our Nigerian Invoicing Guide and our companion post on credit notes in Nigeria.