What Is a Price Difference Invoice? When and How Is It Issued?

A price difference invoice (fiyat farkı faturası) is a supplementary invoice issued when the price increases or decreases after the delivery of goods or the performance of a service has already been invoiced. It references the original invoice and records only the difference.

The goods stay with the buyer; only the price is corrected. That is why it should not be confused with a cancellation or a return.

When is a price difference invoice issued?

The most common cases are:

• Later price increase: The raw material clause in the contract kicks in for a wholesale batch you sold, and you agree with the buyer to raise the unit price.
• Later discount: After the invoice is issued, you give a discount to a dealer that hit its sales target, or to a buyer because of late delivery.
• Exchange rate difference: A sale invoiced in foreign currency is collected on a date when the exchange rate has changed. In practice, this is also called an exchange rate difference invoice (kur farkı faturası).

Under the VAT (KDV) Law in Türkiye, amounts such as price differences, exchange rate differences and late payment differences are included in the VAT base. So when a difference arises, its VAT must also be calculated.

Marketplace sellers run into this mostly with corporate (B2B) orders and wholesale. Later price changes are rare in sales to individual consumers.

Seller and buyer side: who issues the invoice?

If the price drops and the buyer is an end consumer, things change, because a consumer cannot issue an invoice. In that case, you need to plan how the document will be issued together with your accounting records.

The document type is chosen based on the status of the party issuing the invoice:

• If the issuer is an e-invoice (e-Fatura) taxpayer and the other party is a registered user with the Turkish Revenue Administration (GİB), an e-invoice is issued.
• If the issuer is an e-invoice taxpayer and the other party is not a registered user, an e-archive invoice (e-Arşiv) is issued.
• If the issuer is not an e-invoice taxpayer, an e-archive invoice is issued even if the other party is a registered user.
• In 2026, taxpayers other than those under the simplified method and the business account method cannot issue paper invoices.

Before issuing, check the other party's status with an e-invoice taxpayer lookup.

VAT rate and invoice type

As a rule, the VAT rate on the difference invoice follows the rate of the original supply. For example, 20% is not applied to the price difference of a product taxed at 10%.

The VAT rates currently in force are 1%, 10% and 20%. If the original sale was made before July 10, 2023, during the old rate period (when 8% / 18% applied), assess separately which rate to use.

Points to watch on the invoice type:

• Because the goods do not come back, the IADE (return) type is not the natural fit for this transaction.
• In practice, difference invoices are mostly issued with the SATIS (sale) type, referencing the original invoice.
• If the original sale involved VAT withholding (tevkifat) or was exempt, the type of the difference invoice may be shaped accordingly.

You can find the general logic of the types in our guide to e-invoice scenarios and invoice types.

Example: later price increase in a wholesale sale

For example, a kitchenware seller invoiced 100 units to a corporate customer at a unit price of 200 TL (20% VAT). A week later, the parties agreed to raise the unit price to 210 TL under the contract's raw material clause.

The seller does not cancel the original invoice. It issues a separate invoice only for the 10 TL unit difference:

Since the buyer is a corporate taxpayer, it deducts the VAT; in this example, its real cost is the total tax base.

In the description field of the difference invoice, write:

• The number and date of the original invoice
• The reason for the difference (e.g., "price difference under contract clause X")

In the quantity field, enter the number of units and use C62 as the unit code for pieces. To break out the rate and convert between VAT-inclusive and VAT-exclusive amounts, see our VAT calculation article.

Price difference invoice vs. return invoice

The two documents are often confused, because both reference the original invoice and correct the amount. The key distinction: in a return, the goods come back; with a price difference, the goods stay where they are.

Hatalı fatura (an incorrect invoice) follows a different path: the primary route is cancellation or objection within 8 days after the document is delivered to the buyer; once this period has passed, the GİB system does not allow a cancellation request. If the deadline has passed, determine with your accountant which document to use for the correction. For details, see our article on e-invoice and e-archive cancellation, objection and return invoices.

Practical notes for marketplace sellers

• Trendyol campaigns: For coupons and discounts funded by Trendyol, the seller issues a separate e-invoice to Trendyol (Finance > Invoice Listing > Invoices I Need to Issue to Trendyol). This is not a difference invoice. Since there is no explicit GİB regulation on how a marketplace-funded discount should be reflected on the customer invoice, confirm the practice with your accountant.
• Seller discount: Show a discount you fund at the time of sale as a discount on the customer invoice, not later through a difference invoice.
• Corporate order: If the price changes after an order placed on the marketplace with a tax number, determine the document type again. If the issuing party is an e-invoice taxpayer and the other party is a registered user, the difference invoice is an e-invoice.