e-Invoicing in Serbia 2026: who must comply, deadlines, and how
Who must use e-Invoices via SEF in Serbia, the sending and acceptance deadlines, and how to run it all from one tool.
Serbia’s System of Electronic Invoices (SEF) is no longer news — it is now part of everyday business. Yet the same questions keep coming up: who exactly must send e-Invoices, by when, and how to keep it from becoming yet another program to learn. Here is a short, practical guide.
Who must comply
The rule is simpler than it sounds: e-Invoicing is mandatory in dealings with the public sector (B2G) and also between VAT payers (B2B). If you are VAT-registered or work with the state, e-Invoicing applies to you.
- VAT payers — issuing and accepting e-Invoices via SEF
- Public-sector entities — both issuing and mandatory acceptance
- Voluntary users — flat-rate entrepreneurs who want a clean trail and easier work with companies
Deadlines you can’t miss
The most common mistake isn’t in issuing but in accepting. An incoming e-Invoice must be accepted or rejected within the prescribed window — if you stay silent, after the deadline the system treats it in a way that usually isn’t in your favor. So someone should watch SEF daily, or have a tool do it and alert you.
How to keep it painless
The trick is to keep invoicing, the fiscal receipt and the e-Invoice in one place. Ring up a sale once and the outgoing e-Invoice is built for you, while incoming ones land on the same screen — no retyping across three programs. Tezga eKasa and Magaza work exactly that way.
Key takeaways
- VAT payer or working with the state = e-Invoicing is mandatory
- Track both issuing and acceptance — the acceptance deadline is easy to miss
- Keep invoicing and SEF in one tool to avoid double entry
Frequently asked questions
If they are not VAT-registered and don’t work with the public sector, generally no — but many adopt them voluntarily because partner companies expect it and it keeps a clean trail.
After the deadline the system applies a default outcome that usually isn’t in your favor. Daily monitoring, or a tool that reminds you, is best.
What you get with Tezga eKasa
- Outgoing and incoming e-Invoices via SEF in one tool
- Automatic alerts for the acceptance deadline
- Fiscal receipt and e-Invoice from a single sale
- Delivery and credit notes in the same flow
Read more
The KPO book for flat-rate entrepreneurs: what it is, the 6M limit, how to keep it → Fiscalization for freelancers and service businesses: what you actually need → How long to keep which documents by law (and how not to toss them too early) →Try Tezga eKasa free
Fiscal receipts and e-invoices for service businesses — a register that keeps it simple.