When establishing a company in Turkey, you may encounter terms such as e-Fatura, e-Arşiv, e-Defter, e-Mühür and e-İmza, sometimes presented as though they were one system. They are not interchangeable: some relate to issuing invoices, others to accounting ledgers, while the remaining terms concern electronic signatures or seals.

The short answer

• e-Fatura and e-Arşiv: two routes for issuing invoices electronically.
• e-Defter: relates to electronic accounting ledgers, not issuing an invoice to a customer.
• e-Mühür and e-İmza: terms that are separate from the invoice and ledger. The approved information available for this article does not detail the conditions for using each one or their technical and legal implications. A specialist should therefore confirm what the company needs based on its circumstances.

First: What is the difference between e-Fatura and e-Arşiv?

Both are part of electronic invoicing, but they should not be treated as two names for the same route.

e-Fatura

e-Fatura is one of the two electronic invoicing levels identified in the approved information. It becomes mandatory for businesses whose annual sales exceed TRY 3 million, while certain sectors are also subject to mandatory enrollment based on the nature of their activity.

This means that annual sales are not always the only factor. The company’s sector may also affect whether e-Fatura is mandatory. The available information does not include a detailed list of these sectors, so the business activity should be reviewed with the company’s certified accountant.

e-Arşiv

If a company has not reached the mandatory enrollment threshold for e-Fatura and does not operate in a sector subject to a separate requirement, it issues its invoices electronically through e-Arşiv.

From 1 January 2026, the previous TRY 3,000 threshold associated with issuing e-Arşiv invoices was removed. According to the approved information, every invoice must therefore be issued electronically, regardless of its value.

In practice, not being enrolled in e-Fatura does not mean that a company can return to paper invoices. The usual route is instead e-Arşiv.

Second: What is e-Defter?

e-Defter is not an invoice type. An invoice documents a sale or the provision of a service, whereas e-Defter concerns maintaining accounting ledgers electronically.

According to the approved 2026 information, e-Defter is mandatory for businesses whose annual sales exceed TRY 3 million, as well as for certain sectors. Moving to e-Defter may therefore depend on annual sales or the classification of the company’s activity.

Managing e-Defter is part of the company’s accounting cycle. It should be coordinated with the certified accountant rather than treated as a standalone invoicing program. You can also read about the importance of hiring a certified accountant to manage your tax obligations in Turkey.

Third: Where do e-Mühür and e-İmza fit?

A common mistake is to treat e-Mühür or e-İmza as a type of electronic invoice. In practice, both terms are separate from the invoice document itself and from electronic accounting ledgers.

However, the approved information supplied for this article does not specify:

• The detailed legal and technical definition of each one.
• The circumstances in which one is used instead of the other.
• How the requirements differ depending on whether the user is an individual or a company.
• Issuance and renewal procedures or the relevant providers and authorities.

It would therefore be inaccurate to assume that every company needs both in the same manner or that one automatically replaces the other. A specialist should review the company type, the authorised user and the electronic systems in which the company will enroll before determining the appropriate requirement.

A brief practical comparison

| Term | Primary function supported by the approved information | Is it an invoice? | |---|---|---| | e-Fatura | Electronic invoicing route for businesses subject to mandatory enrollment | Yes | | e-Arşiv | Electronic invoicing route for businesses outside e-Fatura | Yes | | e-Defter | Electronic maintenance of accounting ledgers | No | | e-Mühür | Term associated with an electronic seal; detailed use requires specialist confirmation | No | | e-İmza | Term associated with an electronic signature; detailed use requires specialist confirmation | No |

What does this mean when establishing a company in Turkey?

When preparing the company’s accounting infrastructure, do not begin by purchasing a tool simply because you have heard its name. The proper sequence starts with determining:

1. The company type and business activity.
2. Whether its activity places it in a sector subject to a specific system.
3. Its actual or expected annual sales.
4. The appropriate invoicing route: e-Fatura or e-Arşiv.
5. Whether e-Defter applies to the company.
6. Which authentication or signing method is required for the systems it will use.

If you are still at the planning stage, this guide to establishing a company in Turkey will help you understand the broader framework before arranging your invoicing and accounting systems.

Conclusion

Electronic invoicing is not a general term for every digital accounting tool. e-Fatura and e-Arşiv relate to issuing invoices, while e-Defter concerns accounting ledgers. e-Mühür and e-İmza have different functions, and their requirements should be determined according to the company’s circumstances.

Based on the approved 2026 information, every invoice must now be issued electronically regardless of its value. Enrollment in e-Fatura and e-Defter remains linked to the TRY 3 million annual-sales threshold and certain sectors.

To arrange the appropriate system for your business activity and avoid enrolling in an unsuitable route, get a consultation from Aldewan Consulting.