Switching from an employment contract (umowa o pracę) to B2B cooperation is a popular model in Poland: lower social contributions, the 19% flat tax or the lump-sum tax, more flexibility. But if your new client is your former employer, several restrictions apply — and many people only learn about them after receiving a letter from the tax office or ZUS. Here is what the law says.

1. The 19% flat tax — you can lose it for the whole year

Under Art. 9a(3) of the PIT Act, if an entrepreneur provides a former (or current) employer with services corresponding to the duties they performed under an employment relationship in the same tax year, they lose the right to flat-rate taxation for that year.

The consequence: mandatory transition to the progressive tax scale (12%/32%) and back payment of tax advances with interest.

The good news: it is enough to wait until the end of the tax year in which the employment relationship ended. From the following year, the flat tax is available again.

An important nuance: the law refers to the identity of activities, not the mere fact of cooperation. If the scope of B2B services genuinely differs from your former job duties, the restriction does not apply. But you need to be able to prove that difference: a clear description of services in the contract, a different nature of tasks, different deliverables.

2. The lump-sum tax (ryczałt) — an even stricter rule

For the registered lump-sum tax (ryczałt ewidencjonowany), Art. 8(2) of the Lump-Sum Tax Act applies: the exclusion covers not only the year in which the work was performed under the employment contract, but also the following year.

So if you left your job in 2025, the lump-sum tax for services to your former employer only becomes available from 2027. The "waiting period" here is effectively longer than for the flat tax.

3. Preferential ZUS contributions — not for cooperation with an ex-employer

The ulga na start (6 months without social contributions) and preferential contributions (base of 30% of the minimum wage) do not apply if the business activity is performed for a former employer for whom, in the current or previous calendar year, you performed activities falling within the scope of your current business (Art. 18(1) of the Entrepreneurs' Law, Art. 18a of the Social Insurance System Act). The same rule applies to Mały ZUS Plus.

The criterion is the same: identity of activities, not the entity itself. If what you do for your former employer is genuinely different, the reliefs remain available.

4. The biggest risk: reclassification as an employment relationship

Art. 22 § 1 and 1¹ of the Labour Code provides that if cooperation in fact bears the features of an employment relationship, it is an employment relationship — regardless of what the contract is called. The features examined by courts, the National Labour Inspectorate (PIP), ZUS and the tax office are:

• work performed under the client's direction,
• at a place and time designated by the client,
• no business risk on the contractor's side,
• no liability of the contractor towards third parties.

Additionally, Art. 5b(1) of the PIT Act excludes from the definition of business activity any activities that meet all three of the following conditions simultaneously: the client bears the liability, the work is performed under the client's direction at a designated place and time, and the contractor bears no business risk.

What this means in practice:

• a court finding that an employment relationship exists (upon the contractor's claim or following a PIP inspection),
• retroactive assessment of ZUS contributions — up to 5 years back — plus interest,
• the tax office challenging your costs and chosen form of taxation.

The risk is particularly high precisely in cooperation with a former employer: factual continuity (the same office, the same supervisor, the same tasks, a copy-pasted scope of duties) is very easy to demonstrate.

5. What the contractor loses and what the client risks

The contractor on B2B loses the protection of the Labour Code: paid leave, notice periods, protection against dismissal, sick pay on employee terms. Contractual liability is unlimited, whereas under an employment contract, liability for unintentional damage is capped at three months' salary (Art. 119 of the Labour Code).

The former employer, in the event of reclassification, risks back payment of contributions, PPK obligations, and potentially a fine under Art. 281 § 1(1) of the Labour Code — from PLN 1,000 to PLN 30,000.

How to limit the risks: a short checklist

1. Genuinely change the scope of services compared to your former duties — and describe it clearly in the contract.
2. Ensure the contractor's independence: own equipment, flexibility as to place and time, the right to use subcontractors.
3. Include in the contract the contractor's liability towards third parties and a real business risk.
4. Ideally, have more than one client.
5. Before choosing your form of taxation, check whether cooperation with your former employer "blocks" it in your specific year.

---

This article is for information purposes only and does not constitute legal advice. Every situation requires individual analysis — the form of taxation, the dates on which the employment relationship ended, and the actual substance of the cooperation are decisive. If you are planning a switch to B2B or are already working with your former employer, get in touch: we will analyse your situation and design a safe cooperation model.