What Is a Financial Seal (Mali Mühür)? How Do You Get One and What Is It for?

The short answer to what a financial seal is: a financial seal (mali mühür) is an electronic certificate that signs electronic documents such as e-invoices (e-Fatura) on behalf of an organization or taxpayer. It is the electronic equivalent of the stamp and signature on a paper invoice. It proves who issued the document and that it hasn't been altered afterward.

What is a financial seal, and how is it different from an e-signature?

The financial seal is most often confused with the e-signature (e-imza). Both are electronic certificates, but they belong to different owners. An e-signature belongs to a natural person, while a financial seal belongs to an organization or taxpayer.

This distinction has direct consequences depending on your company type:

• Limited and joint-stock companies are legal entities. They use a financial seal to sign documents in their own name. A partner's or manager's personal e-signature is not valid on behalf of the company.
• Sole proprietorships are natural-person taxpayers. In the e-invoice applications of the Turkish Revenue Administration (GİB), they can use the business owner's e-signature. They can also get a financial seal if they wish.

What is a financial seal used for?

You need a financial seal for methods where you sign documents yourself. If a service provider handles the signing, the need may disappear. This is the point sellers confuse most often.

Using the portal: On the GİB portal, you prepare each invoice one by one and sign it from a computer with a card reader plugged in. This may be enough for a business with a few invoices a day. For a seller receiving dozens of marketplace orders a day, this method is not practical.

Direct integration: This is the method used by large businesses that connect their own software to GİB. It requires technical infrastructure, security and ongoing maintenance. It is rarely suitable for small sellers.

Private integrator: The integrator transmits your invoices to GİB and also takes care of the signing. That's why you usually don't need to get a separate financial seal. We explain its role in detail in our article what is a private integrator.

For example, if a sole proprietorship selling on marketplaces had gross sales revenue of 500,000 TL or more in 2025, the business must switch to e-invoice and e-archive invoice (e-Arşiv) from July 1, 2026. This threshold is applied based on the business's total gross sales revenue, not just its marketplace sales. A seller like this who wants to invoice orders automatically usually works with a private integrator and doesn't need to get a financial seal. You can check at what revenue level you must switch in our article e-invoice requirement, and calculate your transition date with our article when should I switch to e-invoice.

How do you get a financial seal?

The financial seal is issued on behalf of the state by the Public Certification Center (Kamu Sertifikasyon Merkezi, Kamu SM) within TÜBİTAK. Application requirements and fees may change periodically. Check the official Kamu SM page for current information. The general process is as follows:

1. Create an application with your company or business details on Kamu SM's financial seal application screen.
2. Prepare the required documents: for companies, information and authorization documents for the authorized person; for sole proprietors, identity information.
3. Pay the application fee. You'll see the amount on the application screen.
4. Once the certificate and card reader are delivered to you, install the driver software.
5. Store your PIN in a safe place and test the certificate on your computer.
6. Use the financial seal for your GİB e-invoice application and for logging in to the portal.

You can find the whole process, from application to your first invoice, step by step in our e-invoice transition guide.

Common mistakes

• Trying to sign a company invoice with a partner's e-signature. A personal e-signature can't be used on behalf of a limited company; the company's own financial seal is required.
• Getting a separate financial seal after signing up with a private integrator. If the integrator does the signing, this is usually an unnecessary expense. Ask your integrator before getting one.
• Leaving the financial seal tied to a single computer. When that computer breaks down, you can't issue invoices, but the 7-day invoicing deadline keeps running. We explain this deadline in our article within how many days must an invoice be issued.
• Getting the timing of the e-ledger obligation wrong. All taxpayers keeping books on a balance-sheet basis have been subject to e-ledger (e-Defter) since January 1, 2025. Those who become required to switch to e-invoice during the year keep e-ledgers from the start of the following year. If you keep books on a business account basis, switching to e-invoice does not by itself mean you've moved to the balance-sheet basis; confirm your bookkeeping type, your e-ledger status and which certificate will be used to sign your ledgers with your certified public accountant (mali müşavir).