Late Paušal Tax Payment in Serbia: Interest, Penalties, and Enforced Collection

Last updated: August 2026. Reflects the Zakon o poreskom postupku i poreskoj administraciji (ZPPPA), the Zakon o porezu na dohodak građana (ZPDG, consolidated through "Sl. glasnik RS", br. 6/2026) and the Zakon o doprinosima za obavezno socijalno osiguranje (ZDOSO). The NBS reference rate quoted below is the rate published on nbs.rs on 21 August 2026.

The date the interest clock starts from

The monthly paušal obligation is due within 15 days of the end of the month it covers (ZPDG čl. 110 t. 1). The social contributions attach to that same date, because ZDOSO čl. 60 st. 1 defers to the ZPDG deadline.

In ordinary months that means the 15th. Where the 15th falls on a weekend or a public holiday, the due date moves to the next working day: in 2026, the January obligation fell due on 18 February, because of the February holidays. Poreska uprava began delivering the 2026 rešenja into the ePorezi tax mailbox on 19 January 2026.

Interest begins on the day after the due date, not on the 15th itself and not at the end of the month. The mechanics of the four separate transfers — accounts, model 97, the BOP from your rešenje — are covered in how to pay your paušal taxes.

A quiet month does not pause anything

A paušalac owes the full assessed amount in a month with no invoices at all. There is no neoporezivi iznos in this regime.

The tax is 10% of the lump-sum income determined in your rešenje (ZPDG čl. 38), and the contribution base is that same assessed figure — "za preduzetnike koji porez plaćaju na paušalno utvrđeni prihod osnovica doprinosa je paušalno utvrđen prihod" (ZDOSO čl. 22 st. 3). Neither figure is derived from what you actually invoiced this month.

This is the point readers most often get wrong before they get the interest question wrong. The obligation runs off the tax decision, not off your turnover, so a slow quarter produces exactly the same monthly amount and exactly the same interest exposure if it goes unpaid.

The interest rate: reference rate plus ten points

Late-payment interest on tax is the NBS reference rate plus 10 percentage points (ZPPPA čl. 75 st. 1–4). At the reference rate of 5.75% published by the National Bank of Serbia in August 2026, the annual tax interest rate is 15.75%.

The figure circulating in most blog posts, forum answers and AI-generated summaries is 13.75% — the reference rate plus 8 points. That is the civil zatezna kamata, the default interest on unpaid money debts between private parties. It is a real rate under a real law; it is simply not the rate the Poreska uprava charges you.

How the interest is computed

ZPPPA čl. 75 st. 1–4 also fixes the arithmetic, and it is simpler than most people expect:

• Simple interest. No compounding within a period.
• Per calendar day, against a 365-day year — 366 in a leap year.
• From the day after the due date until the day the debt is settled.
• On the unpaid balance of each obligation, so a partial payment reduces what the interest runs on from that day forward.

Applying that to a round number: a balance of 20,000 RSD left unpaid for 30 days at 15.75% produces 20,000 × 0.1575 × 30 ÷ 365 ≈ 259 RSD of interest.

That is arithmetic on the statutory formula, offered to show the shape of the calculation. The figure that counts is the one the Poreska uprava books on your taxpayer card, which reflects the exact days, the exact balances and any reference-rate change inside the period.

Checking what you actually owe

The authoritative record of your debt is the stanje na poreskoj kartici on the ePorezi portal. It lists each obligation, the payments booked against it, and any interest assessed.

To reach it you need a kvalifikovani elektronski sertifikat or an eID account, the same credentials you use to receive your rešenje. Menu labels on the portal change from time to time; the item you want is the taxpayer-card view.

Two things regularly surprise people who open the card for the first time. A payment made with last year's BOP may sit unallocated, so an obligation reads as unpaid even though the money left your account — that is a preknjižavanje case, described in how to pay your paušal taxes. And interest may appear as a separate small line rather than being folded into the principal.

Interest and a fine are two different things

Interest is automatic; a fine is not. Interest is arithmetic that runs the moment a due date passes. A monetary penalty is a prekršaj outcome that arises through a control procedure, and it is not a surcharge that attaches to every late payment.

The KPO line deserves a note, because it catches people who assumed the bookkeeping rule and the payment rule live in the same law. They do not. ZPDG contains no prekršaj for failing to keep the KPO — the sanction runs entirely through ZPPPA čl. 178b st. 2, and the same range covers failing to produce the book when the inspector asks for it.

What belongs in the book, and what does not, is in the KPO knjiga guide.

The enforced-collection ladder

Enforced collection (prinudna naplata) is a sequence, not a single event. Serbian practitioner sources describe it consistently in these steps:

1. An opomena — a warning notice giving five days to settle the debt voluntarily.
2. A rešenje o prinudnoj naplati if the deadline passes.
3. The debt is increased by 5%.
4. Collection costs of 5% are added on top.
5. Because a preduzetnik is not a separate legal person, the debt is ultimately answered for with personal assets.

This ladder is cross-checked across independent Serbian legal-practice sources rather than quoted from a numbered article, and it is presented that way deliberately: the article numbers governing each step were not verified for this guide.

The same caveat applies to the question people actually search for — a blokada računa. A blocked account is an outcome of enforced collection, not its first move: the rešenje is executed against the taxpayer's funds and assets, and the money in a business account is the most reachable of those. Treat that as reported practice.

If you want to know where you stand, the taxpayer card on ePorezi answers it directly, and the compliance calendar keeps the due dates from arriving unannounced.

An appeal does not stop any of this. ZPPPA čl. 147 st. 1 is flat: "Žalba ne odlaže izvršenje poreskog upravnog akta." The obligation stays due and the interest keeps running while a žalba is pending.

Under čl. 147 st. 2 the second-instance body may postpone execution, but only where the taxpayer documents that paying before the act becomes final would cause substantial economic harm. That is a reasoned exception you have to ask for and evidence, not something an appeal triggers on its own.

What the record does not settle

Three gaps are worth naming, because filling them with a plausible guess is how bad advice spreads.

No statutory deadline for issuing the annual rešenje. No source consulted for this guide identified a rule fixing when the Poreska uprava must issue it. What is documented is the 2026 practice: delivery into the ePorezi mailbox started 19 January 2026 and the first payment fell due 18 February 2026. A date observed once is not a rule.

Electronic delivery is deemed service. A tax act "smatra se dostavljenim danom postavljanja na portal Poreske uprave" (ZPPPA čl. 36), and the same article removes the need for separate consent from anyone who already files tax returns electronically. The practical consequence: the 15-day appeal window (ZPPPA čl. 142, 143) runs from the day the document was posted, whether or not you logged in to read it.

The appeal fee is not stated here. The amount reported in circulation comes from a source that predates subsequent revisions of the administrative-fee schedule. Check the current taksa with Poreska uprava before filing rather than relying on a figure from a blog.

If a payment has already been missed

The procedure is short, and none of it involves negotiating anything.

1. Pay the outstanding obligation using the account, model and BOP from your current rešenje. Interest runs per day on the balance, so the balance is what closes it.
2. Open the taxpayer card on ePorezi and confirm the payment was booked against the right obligation. A correct total paid to the wrong reference does not clear the debt.
3. If interest has been assessed, it appears as its own line and is settled the same way as the principal.
4. If a payment was misallocated, file a zahtev za preknjižavanje with your Poreska uprava office rather than paying twice.
5. If an opomena has already arrived, the five-day window on it is the one that matters — the ladder above starts moving after it lapses.

Key takeaways

1. Late-payment interest on tax is the NBS reference rate plus 10 percentage points under ZPPPA čl. 75 st. 1–4 — 15.75% per year at the 5.75% reference rate in force in August 2026.
2. The 13.75% figure so widely quoted is the civil zatezna kamata (reference rate + 8 points) and belongs to a different law and a different kind of debt.
3. Interest is simple, daily, and runs from the day after the due date against a 365- or 366-day year, on the unpaid balance of each obligation.
4. The monthly obligation is due within 15 days of the end of each month (ZPDG čl. 110 t. 1; ZDOSO čl. 60 st. 1), shifted for weekends and holidays — the January 2026 obligation fell due on 18 February 2026.
5. A month with zero income still carries the full assessed amount, because a paušalac has no tax-free allowance (ZPDG čl. 38; ZDOSO čl. 22 st. 3).
6. A fine is separate from interest: 10%–50% of the tax determined in control with a 50,000 RSD minimum for a preduzetnik is a cross-checked figure tied to a control procedure, while failing to keep the KPO knjiga carries 50,000–500,000 RSD under ZPPPA čl. 178b st. 2.
7. Enforced collection escalates in fixed steps — five-day opomena, rešenje, debt +5%, costs +5%, then personal assets — and the taxpayer card on ePorezi is where you see it coming.
8. An appeal does not suspend payment (ZPPPA čl. 147 st. 1). Only the second-instance body can postpone execution, and only where the taxpayer documents that paying early would cause substantial economic harm (čl. 147 st. 2).

Frequently asked questions

What interest rate applies when a Serbian paušalac pays the monthly tax late?

Late-payment interest on tax in Serbia is the National Bank of Serbia reference rate plus 10 percentage points, under ZPPPA article 75. With the reference rate at 5.75% in August 2026, that works out to 15.75% per year. The formula is fixed by statute, but the reference rate moves, so the resulting percentage changes whenever the NBS changes its rate.

Is the tax late-payment interest in Serbia the same as zatezna kamata?

No. Tax interest is the NBS reference rate plus 10 percentage points under ZPPPA article 75, while the civil default interest known as zatezna kamata is the reference rate plus 8 percentage points under a separate law. At a 5.75% reference rate that is 15.75% for tax and 13.75% for civil money debts. Sources that quote 13.75% for unpaid tax are applying the wrong statute.

When is the monthly paušal tax due in Serbia?

The monthly paušal income tax is due within 15 days of the end of the month it covers, under ZPDG article 110 point 1, and the social contributions follow the same deadline under ZDOSO article 60. In practice that means the 15th of the following month, moved forward when the 15th falls on a weekend or a public holiday. The January 2026 obligation, for example, fell due on 18 February 2026.

Does a Serbian paušalac still owe the monthly tax in a month with no income?

Yes. A paušalac has no tax-free allowance: the tax is 10% of the lump-sum income assessed in the rešenje under ZPDG article 38, and the contribution base is that same assessed figure under ZDOSO article 22. Actual turnover in a given month does not change the amount, so a quiet month or a month with no invoices at all does not pause the obligation or the interest clock.

Is there a fine for paying paušal tax late in Serbia, or only interest?

Interest is the automatic consequence and it runs per calendar day from the day after the due date. A monetary fine is a separate matter that comes out of a tax control procedure rather than from the late payment itself: practitioner sources report a range of 10% to 50% of the tax determined in control, with a minimum of 50,000 RSD for an entrepreneur. That figure is cross-checked rather than quoted from the statute.

What is prinudna naplata and how does it work against a Serbian preduzetnik?

Prinudna naplata is the enforced collection of an unpaid tax debt by the Poreska uprava. Serbian practitioner sources describe a consistent sequence: a warning notice giving five days to pay, then a decision on enforced collection, an increase of the debt by 5%, and collection costs of a further 5%. Because an entrepreneur is not a separate legal person, the debt is ultimately answered for with personal assets.

Can the Poreska uprava block a paušalac's bank account for unpaid tax?

A blocked account is an outcome of enforced collection, not the first step. The reported sequence starts with a five-day warning notice and a decision on enforced collection, after which the debt is pursued against the taxpayer's funds and assets. The precise statutory list of collection instruments was not verified for this guide, so treat the account-blocking description as reported practice and check your own position on ePorezi.

How can a Serbian paušalac check how much tax they owe on ePorezi?

Log in to the ePorezi portal with a qualified electronic certificate or an eID account and open the taxpayer card, the stanje na poreskoj kartici. It shows each obligation, the payments booked against it, and any outstanding balance including interest the Poreska uprava has assessed. The card is the authoritative figure; arithmetic you do yourself with the interest formula is only an estimate.

What is the fine for a paušalac not keeping the KPO knjiga in Serbia?

Failing to keep the prescribed business books, or failing to produce them on request, carries a fine of 50,000 to 500,000 RSD for an entrepreneur under ZPPPA article 178b. This is a separate offence from paying tax late, and it runs through the procedural law: the income tax law itself contains no misdemeanour provision for the KPO. Keeping the book current is the cheapest part of the obligation to get right.

How is late-payment interest on Serbian tax calculated day by day?

Interest under ZPPPA article 75 is simple interest, not compounded within the period, calculated per calendar day against a 365-day year, or 366 in a leap year, and it runs from the day after the due date until the day the debt is paid. At an annual rate of 15.75%, a balance of 20,000 RSD outstanding for 30 days produces roughly 259 dinars of interest. The amount the Poreska uprava books on your tax card is the one that counts.

Sources

• Zakon o poreskom postupku i poreskoj administraciji (ZPPPA) — čl. 36 (electronic service), čl. 75 st. 1–4 (interest), čl. 142 and čl. 143 (appeal), čl. 147 st. 1–2 (an appeal does not suspend execution), čl. 178b st. 2 (books penalty).
• Zakon o porezu na dohodak građana (ZPDG) — čl. 38 (10% rate, no allowance), čl. 110 t. 1 (payment deadline).
• Narodna banka Srbije — referentna kamatna stopa — the 5.75% reference rate underlying the 15.75% figure.
• Poreska uprava — Preduzetnici paušalci — the authority's own overview of the regime.
• ePorezi portal — the taxpayer card (stanje na poreskoj kartici) and electronic delivery of rešenja.