How much does reclassifying a B2B contract into an employment contract cost, real ZUS and PIT numbers

How much does reclassifying a B2B contract into an employment contract cost, real ZUS and PIT numbers

How many years back can debt be assessed

ZUS and the tax office can reach back 5 years from the day a contribution or tax was due, not just from the day of a PIP inspector’s decision. For ZUS contributions, this period is set by Article 24(4) of the Social Insurance System Act (hereafter, the ZUS Act). For tax, the period is identical, 5 years from the end of the calendar year in which the payment deadline passed, under Article 70 § 1 of the Tax Ordinance¹.

That’s not even the worst part. While an appeal is pending, years of accumulated debt “freeze” rather than expire. A new Article 24(5h) of the ZUS Act suspends the statute of limitations from the day an appeal is filed against a PIP decision until the day the decision becomes final, or until a court ruling becomes legally binding¹. An equivalent rule applies to tax: a new Article 70 § 6(3a) and (3b) of the Tax Ordinance suspends the limitation period for the entire duration of court proceedings concerning a PIP decision⁶. The practical consequence: if an inspection starts in 2026 but a court doesn’t issue a final ruling until 2028, debt from 2021 doesn’t have time to expire, and the limitation period starts counting again from 2028.

There’s one more detail rarely explained: the tax office can’t decide on its own that a working relationship was employment. A new Article 201 § 1aa of the Tax Ordinance treats a final PIP decision or a legally binding court judgment finding an employment relationship as prejudicial: a binding fact for the tax proceedings⁷. That means the tax office first suspends its own case, waits for the final PIP decision, and only then assesses tax based on the already-established fact, without the right to re-evaluate whether it was employment.

Reclassification debt doesn’t expire while a dispute is ongoing: an appeal against a PIP decision suspends the limitation period for both ZUS and tax at the same time.

Who actually pays the debt, and why it isn’t the contractor

The ZUS and PIT debt for the past period is legally enforced against the company, not the former contractor, even though part of the contributions and tax economically corresponds to the “employee’s share.” The reason is the company’s status as a remitter (płatnik): an entity obligated to calculate, withhold, and transfer contributions or tax on behalf of another person. Article 30 § 1 and § 3 of the Tax Ordinance states directly that a remitter who fails to fulfill this obligation is liable for unwithheld tax, or tax withheld but not transferred, with their entire assets⁸. The same rule applies to ZUS contributions through Article 23 of the ZUS Act, which refers to the Tax Ordinance’s rules on debt enforcement⁹.

Example. A company worked with a developer on a JDG for two years, paying PLN 12,000 a month on invoice, and no one withheld or transferred anything to ZUS or the tax office beyond what the contractor himself paid as an entrepreneur. PIP found an employment relationship. The tax office and ZUS demand the assessment directly from the company, not from the contractor, including the portion of contributions and tax that a regular employment arrangement would withhold from the employee’s pay. Can the company demand that amount back from the former contractor?

In theory, yes, through a civil claim for unjust enrichment, but that’s a separate, slow, and uncertain court dispute, not an automatic right of offset¹⁰. The company pays the debt to the state regardless of the outcome of that future dispute.

Contributions the contractor already paid as a JDG don’t disappear

Social insurance contributions a contractor paid as a JDG for a period recognized as employment are credited against the contributions the employer should have paid for the employee. This is established by a new Article 38b of the ZUS Act: contributions paid under a JDG or a mandate contract are treated as paid toward the corresponding employee contributions for the same period². The company only pays the difference, not the full amount of contributions from zero, and must submit the relevant documents to ZUS within 7 days of the PIP decision becoming final².

This is the most important detail for the real amount of debt, and it’s exactly what most online calculators miss: they calculate the full cost of employee contributions as if the contractor paid nothing at all. How large the credit is depends on which ZUS variant the contractor paid as an entrepreneur: full (“large”) ZUS credits much more than the discounted rate. This rule applies only to social contributions (pension, disability, sickness, the future accident contribution). The health contribution (equivalent to NFZ) and tax the contractor paid as an entrepreneur are not included in this mechanism: the law doesn’t provide for an automatic credit for them, so the risk of double burden remains higher there.

How much a single contractor really costs, a simulation example

This is a simulation example, not a ready-made figure for your case. Advice on the specific amount in your situation is a job for an accountant who accounts for the taxation form, the entrepreneur’s real expenses, and the date of each payment.

Simulation conditions: the contractor was invoicing PLN 12,000 a month (the same example as Dmytro, the single-client developer we covered in the series article “7 signs your B2B contract is disguised employment“). PIP found an employment relationship going back 12 months. For the calculation, we took the invoiced amount as the contribution and tax base for an employment contract, a simplification, because the real outcome depends on whether the contract defined that amount as “net” or as “gross” for the future employee, and that’s exactly the point worth checking with an accountant before any negotiations with the company.

Based on PLN 12,000, after reclassification the company must secure every month:

Total needed every month: PLN 5,935. This is before accounting for the Article 38b credit.

Scenario A: Dmytro on full (“large”) ZUS. Dmytro has been on a JDG since 2023, more than 24 months, so he’s no longer eligible for discounted ZUS. In 2026, full social ZUS is PLN 1,926.76 a month¹¹. This amount is credited against the employer and employee contributions (PLN 2,446+1,645=4,091 needed), leaving a social contribution debt of PLN 2,164 a month. Add the health contribution (PLN 932) and PIT advance (PLN 913), which the credit doesn’t cover: PLN 4,009 of debt a month, or PLN 48,100 over 12 months. Is that the final figure?

No. Interest for late payment still needs to be added.

Scenario B: Solomiya on discounted ZUS. Solomiya has only been on a JDG for her first year and pays discounted ZUS: PLN 456.19 in social contributions a month¹¹. The credit is smaller, so the social contribution debt = 4,091−456=PLN 3,635 a month. Combined with the health contribution and PIT: PLN 5,479 a month, or PLN 65,700 over 12 months. Is the company’s debt the same for two contractors invoicing the same amount?

No. The difference in which ZUS scheme the contractor chose costs the company an extra PLN 17,600 a year, and the company has no control over that choice.

Interest for late payment is added to both figures: since 5 March 2026, the base interest rate for late payment of contributions and taxes has been 10.5% per year⁴. Because the debt accumulated gradually over the year, the approximate interest-accrual period for the full amount is roughly half a year, so roughly another PLN 2,500-3,500 on top of each scenario, depending on the exact dates. That’s an approximation, not a precise day-by-day calculation, and it doesn’t account for interest continuing to accrue every month the proceedings and any appeal are ongoing.

Simulation summary for 12 months, one contractor, PLN 12,000/month, before any fine: roughly PLN 50,600-69,100, depending on which ZUS variant the contractor paid as an entrepreneur.

This amount is consistent, order of magnitude, with the illustrative example from the series article “B2B contract audit before PIP”: it cited an estimate from a Polish law firm of over PLN 300,000 to reclassify a contract worth PLN 15,000 net over three years back¹². Scaled down to one year, that’s roughly PLN 100,000 for a higher contract amount, the same order of magnitude as in our simulation for a smaller amount and a shorter period.

What the PIP fine adds on top of this amount

The fine under Article 281 § 1 of the Labor Code doesn’t replace the ZUS and PIT debt, it’s added to it. A court can impose a fine of PLN 2,000 to 60,000 for substituting an employment contract with a civil-law contract, and if the affected worker is registered as a debtor for alimony arrears in the National Debtors’ Register, from PLN 3,000 to 90,000³. A regular repeat offense without that circumstance stays within the same PLN 2,000-60,000 range. That’s the same range we cited in the series articles on the contract-fix checklist and on B2B contract audits, and the court sets the specific amount within that range, not automatically the maximum.

Example. The company from the example above, with a debt of PLN 48,100-65,700 for one contractor, also receives a court ruling imposing a PLN 15,000 fine for a first offense. Does that mean the total is PLN 63,100-80,700?

Yes. The fine and the ZUS/PIT debt are two separate, independent payments, and neither one covers the other.

Can these figures be reduced before 8 July 2027

The voluntary transition window to an employment contract reduces only the fine, not the ZUS and PIT debt for the past period. Until 8 July 2027, a transition period applies during which a company that transitions a contractor to an employment contract on its own, before a PIP inspection, is exempt from the fine under Article 281 § 1 of the Labor Code⁵. This window doesn’t cover the ZUS and PIT debt for the period when the contract actually had the features of employment: contributions and tax are assessed based on the actual, not the formal, status of the arrangement, regardless of when the company fixed the situation.

Example 1. A company transitions three contractors to employment contracts on its own in March 2027, before any PIP inspection. Is the company exempt from the fine for the past two years of B2B cooperation?

Yes. A voluntary transition before the deadline and before an inspection begins exempts the company specifically from the fine under Article 281 § 1 of the Labor Code.

Example 2. The same company hopes the ZUS debt for those two years will also disappear along with the fine. Is that the case?

No. ZUS and the tax office can assess contributions and tax for the actual period of cooperation regardless of the date of the voluntary transition, within the bounds of the 5-year limitation period.

The most financially advantageous strategy, then, isn’t to wait for the final deadline but to review the situation as soon as possible: the sooner working practices are fixed, the shorter the period over which debt can accumulate. We cover how to assess your own risk based on your cooperation profile in the series article “Who risks losing B2B status after the PIP 2026 reform,” and a step-by-step twelve-point checklist for exactly how to fix a contract is in the series article “How to fix a B2B contract under PIP 2026: a 12-point checklist.”

The fine can be avoided entirely through a voluntary transition by 8 July 2027. The ZUS and PIT debt for the actual period of cooperation knows no such window.

Frequently asked questions

How many years back can ZUS assess contributions?

Up to 5 years from the day a contribution was due, and the limitation period is suspended for the entire duration of a court dispute over a PIP decision¹. That means the actual period the debt covers is often longer than 5 years if proceedings drag on.

Does the former contractor have to reimburse the company part of the debt?

Legally, the company pays the debt to the state as the remitter. The company can, in theory, try to recover part of the amount from the former contractor through a civil claim for unjust enrichment, but that’s a separate, slow dispute with an uncertain outcome, not an automatic right¹⁰.

Does the fact that the contractor already paid ZUS as an entrepreneur reduce the debt?

Yes, for social contributions: a new Article 38b of the ZUS Act credits already-paid contributions against the employee’s contributions for the same period². This doesn’t apply to the health contribution or the tax the contractor paid as an entrepreneur, the law provides no automatic credit for those.

Does the voluntary transition window until 8 July 2027 cover the ZUS and PIT debt?

No. It only exempts a company from the fine under Article 281 § 1 of the Labor Code⁵. Contribution and tax debt for the actual period of cooperation is assessed regardless of the date of the voluntary transition.

Does the amount of debt differ depending on which ZUS the contractor paid?

Yes, substantially: in our simulation, the difference between a contractor on full ZUS and a contractor on discounted ZUS is over PLN 17,000 a year for the same PLN 12,000-a-month invoice, because a smaller amount of already-paid contributions means a smaller credit under Article 38b².

Does this simulation include the cost of court proceedings and legal support?

No. The simulation covers only ZUS contributions, the PIT advance, interest, and a possible fine. Attorney costs, management time spent on the proceedings themselves, and a potential civil dispute with the former contractor are calculated separately and aren’t included in the figures above.

What to do with these numbers

The exact amount of debt for your company depends on specific dates, each contractor’s taxation form, and the real working practice, not on one averaged simulation. MojaFirma offers two verification formats depending on your situation.

If you work on a JDG yourself. Order an online B2B audit: fill out a questionnaire about your situation, and within 48 hours you get a report with a risk category and an approximate assessment of the financial consequence for your specific contract.

If you’re the owner or HR of a company with several B2B contractors. Order a B2B operating model audit: it checks contracts, invoices, and ZUS data for each contractor individually, and gives an approximate assessment of the total debt for the whole company, not for one case in isolation. That’s exactly the calculation we did in the series article “B2B contract audit before PIP: what lawyers check and how much it costs.”

Sources

1. Social Insurance System Act, Dz.U. 2026 poz. 199, Art. 24(4) and 24(5h) (added by Dz.U. 2026 poz. 473); Tax Ordinance, Dz.U. 1997 nr 137 poz. 926, Art. 70 § 1
2. Social Insurance System Act, Dz.U. 2026 poz. 199, Art. 38b (added by Dz.U. 2026 poz. 473)
3. Act of 11 March 2026 amending the Act on the National Labour Inspectorate and certain other acts, Dz.U. 2026 poz. 473, Art. 3 (amending Art. 281 § 1 and § 2 of the Labor Code)
4. Announcement of the Minister of Finance and Economy of 6 March 2026 on the interest rate for late payment of tax arrears, M.P. 2026 poz. 269 (10.5% annual rate, also applied to ZUS arrears under Art. 23 of the ZUS Act)
5. Dz.U. 2026 poz. 473, Art. 16 (voluntary adjustment period until 8 July 2027)
6. Tax Ordinance, Dz.U. 1997 nr 137 poz. 926, Art. 70 § 6(3a) and (3b), § 7(3a) and (3b) (added by Art. 4 of Dz.U. 2026 poz. 473)
7. Tax Ordinance, Dz.U. 1997 nr 137 poz. 926, Art. 201 § 1aa (added by Art. 4 of Dz.U. 2026 poz. 473)
8. Tax Ordinance, Dz.U. 1997 nr 137 poz. 926, Art. 30 § 1 and § 3
9. Social Insurance System Act, Dz.U. 2026 poz. 199, Art. 22 (contribution rates) and Art. 23 (reference to the Tax Ordinance for interest)
10. MojaFirma’s own analysis based on Art. 30 of the Tax Ordinance (remitter liability) and Art. 405 of the Civil Code (unjust enrichment); case discussion using a PLN 14,000 net contract example, Grants Capital, 2026 (third-party illustrative example, not MojaFirma data)
11. ZUS contribution levels for entrepreneurs in 2026 (large ZUS PLN 1,926.76, discounted ZUS PLN 456.19, both amounts excluding the health contribution), Firmove, July 2026; PITax, July 2026
12. Simulation of B2B contract reclassification costs, Kancelaria Adwokacka Marcin Orlicki, April 2026 (illustrative example, not MojaFirma data), also cited in the series article on B2B audits

This article does not constitute legal or tax advice. The simulation in this article is approximate: the real debt amount for your case depends on the contractor’s taxation form, the exact payment dates, and the specific ZUS contribution variant, and requires confirmation from a MojaFirma accountant before any decision. Author: Valerii Kushnirskyi, in-house legal practitioner at MojaFirma.