Even a well-run sole proprietorship can hit a month in which a client has not paid on time while the tax office and ZUS, the social insurance institution, are waiting for a transfer. In that situation the worst response is silence and the hope that the problem will disappear on its own — interest accrues, and enforcement follows. Polish law, however, provides three lawful ways of spreading the burden over time: deferral of the payment deadline, payment in instalments, and remission. They operate separately on the tax side and on the ZUS side, and the conditions differ between the two systems.
Three forms of relief under the Tax Ordinance
The basis is Article 67a of the Tax Ordinance (Ordynacja podatkowa). At the taxpayer's request, the tax authority may defer the tax payment deadline or spread the tax payment into instalments, defer or spread into instalments the payment of tax arrears together with late payment interest, and remit in whole or in part the tax arrears, the late payment interest or the prolongation fee.
The difference between the first and the second form of relief is purely a matter of timing, but it matters greatly in practice. You apply for deferral of a tax payment deadline before the deadline expires — for example before the 20th day of the month on which the PIT advance falls due. Once the deadline has passed, the liability becomes tax arrears and the application concerns the arrears together with interest. Remission, in turn, relates only to arrears, interest and the prolongation fee — a tax whose payment deadline has not yet arrived cannot be remitted.
Important interest of the taxpayer or the public interest
The provision sets one substantive condition: granting the relief must be justified by an important interest of the taxpayer or by the public interest. The statute does not define these terms, so the burden of demonstrating them rests with the applicant. The mere fact that paying is inconvenient is not enough. What counts are objective, documentable circumstances: the loss of a principal client, unpaid invoices of material value, serious illness, an event that destroys business assets, a sudden downturn in the sector.
A decision on relief is also discretionary — even if the grounds are made plausible, the authority is not obliged to grant it. The application should therefore be specific: it should state the liability and the period, the amount, the deadline or instalment schedule you propose, and the basis for concluding that you will keep to it. Evidence is attached — payment demands sent to clients, bank statements, a statement of receivables and payables.
What deferral costs — the prolongation fee and interest rates in 2026
Deferral and instalments are not free, but they are distinctly cheaper than simply paying late. For decisions concerning taxes that constitute State budget revenue, the authority sets a prolongation fee equal to 50 percent of the late payment interest rate in force on the date the decision is issued.
The reference point is the current rate of late payment interest on tax arrears. Since 5 March 2026 it has stood at 10.50 percent per annum, the reduced rate is 5.25 percent and the increased rate 15.75 percent. At the basic rate, the prolongation fee thus corresponds to 5.25 percent per year. From the date to which payment has been deferred, late payment interest stops running and is replaced by that fee.
A practical warning: if you miss the deferred deadline or the deadline for any instalment, the decision ceases to have effect and the liability returns to its original state — with interest calculated as though the relief had never existed. Better to propose a cautious schedule than an ambitious one.
Relief for entrepreneurs and de minimis aid
For a person running a business there is an additional layer of rules — Article 67b of the Tax Ordinance. Relief granted to an entrepreneur is usually classified as de minimis aid, that is, public support within the ceiling of EUR 300,000 over three years for a single undertaking.
In practice this means that documents concerning de minimis aid must be attached to the application: declarations or certificates of aid received in the current year and in the two preceding years, together with information on the form prescribed by the State aid rules. Gaps here are among the most common reasons for requests to supplement the file and for the matter dragging on. The classification is made by the authority, so it is better to prepare a complete set from the outset.
ZUS contributions — deferral, an instalment arrangement and remission
ZUS operates its own system of relief and its own forms. Deferral of the deadline for paying contributions is applied for on form RSO, and only contributions whose payment deadline has not yet expired can be deferred. That is the key difference from the tax office and the most common reason for refusal: an application filed after the 20th day of the month has nothing left to defer.
Contributions already in arrears are covered by an instalment arrangement, applied for on form RSR. Once the agreement with ZUS is concluded, late payment interest is no longer charged from the day following the day the application was filed; in its place the contribution payer bears a prolongation fee equal to 50 percent of the interest rate in force on the date the agreement is signed. Concluding the arrangement also halts enforcement proceedings, and if you file early enough, enforcement may never be initiated at all.
The hardest form of relief is remission, applied for on form RSU. Under Article 28 of the Act on the Social Insurance System it is available, as a rule, only where the receivable is wholly irrecoverable — the statute lists the situations in which this is established. An exception applies to contributions to the entrepreneur's own insurance where the entrepreneur is also the contribution payer: these may be remitted in justified cases even without complete irrecoverability. The exception does not extend to contributions for employed persons.
How to file the application and what to keep in mind
Applications to the tax office can be filed in person, by post or electronically — the Biznes.gov.pl portal provides e-services for relief in the payment of tax liabilities. Applications to ZUS are filed through the ZUS electronic portal, by post, in person at a branch, or orally for the record. In both cases the electronic route is faster and gives proof of the filing date, which can be decisive where deferral is concerned.
Three things are worth remembering. First, timing: an application for deferral only makes sense before the payment deadline expires, and where there are arrears you should act quickly, because interest runs until the day the application is filed. Second, relief does not release you from paying current liabilities — falling behind on new payments during an instalment arrangement usually ends in its termination. Third, tax relief and contribution relief are two separate matters before two institutions; the tax office's agreement has no bearing on the position taken by ZUS.