E-invoicing · SEFAvailable

E-invoicing without logging into the SEF portal

An e-invoicing app that works with SEF, Serbia’s e-invoice system, in both directions: send invoices from the app, receive supplier invoices automatically every hour, and accept or reject them in one click. Statuses, cancellation and reversal are in the same place.

Sole traders
Entrepreneurs
LLCs
VAT payers

Already have an account? Log in

We open your account and trial on request. Pricing is agreed with each company.

We send and receive e-invoices this way every day in our own company.

Illustration with sample data · the app interface is in Serbian

the format invoices are sent to SEF in: UBL 2.1
supplier invoices imported, statuses refreshed: Every hour
encryption for your company’s API key: AES-256-GCM
SEF error messages, translated: In Serbian

Outgoing invoices

Send e-invoices straight from the app

Send an issued invoice to SEF with the “Send” button. The app checks the data first.

One-click sending

An issued invoice goes to SEF as UBL 2.1, with no downloading or manual file uploads.

Checked before sending

The app validates required data before sending and translates SEF error messages into Serbian.

Advances, credit and debit notes

Advance invoices (386), credit notes (381), debit notes (383) and final invoices after an advance follow the Ministry of Finance’s official examples.

JBKJS for budget users

When the customer is a public budget user, its JBKJS code is included in the e-invoice. Invoices are not registered in CIR, the central invoice register.

Incoming invoices

Supplier e-invoices arrive on their own

Receiving supplier invoices is available to entrepreneurs who keep books, LLCs and VAT payers, with the supplier invoices module.

Imported every hour

Every hour the app pulls new supplier invoices from SEF. No manual downloads.

Accept or reject

Decide in the app; when rejecting, the reason you enter goes to SEF.

In-app and email notifications

A new supplier invoice shows up in the app’s notification bell and in your inbox.

Statuses

Statuses, cancellation and syncing with SEF

Statuses refresh on their own

Every hour the app checks the status of sent invoices: sent, seen, approved, rejected, cancelled or reversed.

Cancel or reverse

Cancel or reverse an invoice on SEF from the app, without visiting the portal.

Sync with SEF

Link invoices you sent to SEF outside the app to the matching documents in the app.

Is the customer on SEF?

See whether a customer is registered on SEF before sending, and look companies up by tax ID.

For VAT payers

VAT records on SEF and POPDV preparation

Only VAT payers see this part of the app.

Summary VAT records

A draft is built from fiscal receipts and invoices that did not go through SEF. Edit it before sending; history and cancellation are in one place.

Individual VAT records

Individual VAT records for documents that require them.

POPDV preparation

The app prepares the data for the POPDV form; you or your accountant file the return.

Connecting

Your SEF key, encrypted and yours alone

You enter your own API key

Your company enters its SEF key in its own settings. It is stored encrypted (AES-256-GCM) and never shown again.

Data kept separate per company

Each company sees only its own invoices and settings.

Demo SEF for testing

Demo accounts work with a SEF simulator, so you can try the sending flow without real credentials.

How it works

E-invoicing (SEF), step by step

Create an API key on SEF
On the eFaktura portal, generate an API key in your company’s settings.
Enter the key in the app
The key is stored encrypted and is never shown again.
Send and receive
Send outgoing invoices with “Send”; supplier invoices arrive every hour.

Notes

Good to know before you start

We use invoice sending and supplier-invoice import every day. Credit and debit notes, final invoices after an advance and VAT records follow the official examples, but have yet to be confirmed against the live SEF.
The app prepares POPDV data but does not file the POPDV or PP PDV return.
Invoices are not registered in CIR, the central invoice register.
Electronic dispatch notes (e-Otpremnica, SEO) are not part of the app.

Works on desktop, tablet and phone – installs like an app (PWA)

Open invoice.solve.rs in your browser and add it to your phone’s home screen. Nothing to download from an app store. The interface is in Serbian; invoice PDFs can also be in English.

Desktop
Tablet
Phone
Each company’s data kept separate
Hosted in the EU (Frankfurt)

Questions

E-invoicing (SEF): frequently asked questions

Can a sole trader (paušalac) send e-invoices too?

Yes. Every company can send e-invoices from the app, whatever its tax status. Receiving supplier invoices is available to entrepreneurs who keep books, LLCs and VAT payers, and VAT records and POPDV preparation only to VAT payers.

Do I still need to log into the SEF portal?

Not for day-to-day work: sending, receiving, accepting, rejecting and statuses are all in the app. You visit the portal once to create an API key for your company.

How is my SEF API key stored?

The key is stored encrypted (AES-256-GCM) and, once entered, is not shown to you or anyone else in the app. If you change it on SEF, just enter the new one.

How quickly do supplier invoices arrive?

The app checks SEF every hour. A new supplier invoice appears in the list and the notification bell, and you also get an email.

Does the app file the POPDV and PP PDV returns?

No. The app prepares POPDV data and sends VAT records to SEF; you or your accountant file the return.

Can I send e-invoices to public-sector customers?

Partly. The budget user’s JBKJS code is included in the e-invoice, but the app does not register invoices in CIR, the central invoice register, and we have not yet tested invoicing public-sector customers in practice. If that matters to you, let us know before you start.

Can I try sending before connecting the real SEF?

Yes. Demo accounts work with a SEF simulator, and you connect the real SEF with your own API key when you are ready.

Available

Connect SEF and work from one app

Request a trial account, enter your API key and send e-invoices without logging into the portal.

There is no public sign-up: we open the account and get back to you by email.