An employment contract and a sole proprietorship can be combined without any restrictions arising from tax or social insurance rules. Whether the combination is worthwhile depends on three things: the salary from the employment contract (which determines whether the business pays social contributions), the chosen form of taxation for the business and the provisions of the contract with the employer.
Salary vs social contributions from the business
The Act on the Social Insurance System resolves the overlap of titles in favour of the employment contract. An employee who at the same time runs a business is subject to pension and disability insurance only from the employment contract, provided the monthly contribution base from the employment is not lower than the minimum wage. In 2026, this threshold is PLN 4,806 gross.
What counts is the amount, not the working-time rate. A person employed half-time with a salary of PLN 5,000 gross exceeds the threshold, while a full-time employee who, due to absence, received less in a given month may not reach it that month. If the salary is lower than the minimum, the business becomes a second mandatory title for insurance and social contributions must be paid from it.
A few practical consequences:
- with a salary at least equal to the minimum wage, no pension, disability, accident, Labour Fund or Solidarity Fund contributions are paid from the business, but one may join them voluntarily;
- with a lower salary, social contributions from the business are mandatory, but a new entrepreneur may use the start-up relief (6 months without social contributions) and then the preferential base for 24 months;
- neither relief applies when the business performs for a former employer what the person did for them as an employee in the current or previous calendar year.
The details of the first half-year are described in the article on the ZUS start-up relief.
Health contribution paid twice
The exemption from social contributions does not cover health insurance. ZUS states expressly that with several titles the health contribution is paid separately from each of them. The employer deducts it from the salary, and the entrepreneur pays their own contribution from the business under the rules for their form of taxation. In 2026 it looks like this:
| Form of taxation of the business | Health contribution from the business |
|---|---|
| Tax scale | 9% of income, no less than PLN 432.54 per month |
| Flat tax | 4.9% of income, no less than PLN 432.54 per month |
| Ryczałt | PLN 498.35, PLN 830.58 or PLN 1,495.04 per month, depending on annual revenue (thresholds of PLN 60,000 and PLN 300,000) |
At a small scale of additional activity it is the health contribution that often becomes the largest fixed cost. Those planning to earn a few hundred złoty a month in the firm should compare it with unregistered activity, which requires neither CEIDG entry nor the health contribution.
Tax: common threshold or separate returns
The choice of the form of taxation for the business has different effects alongside employment than for someone who lives only from the business.
Tax scale
Income from employment and from the business taxed on the scale is combined in one PIT-36 return. The 12% rate covers a combined base of up to PLN 120,000, the surplus is taxed at 32%, and the tax-free amount (PLN 30,000) is available only once. A well-paid employee may therefore enter the second bracket already with the first złoty from the business.
Flat tax and ryczałt
Under the flat tax (podatek liniowy), business income is settled in a separate PIT-36L return at 19%, and the salary is still taxed on the scale in PIT-37. Ryczałt (the PIT-28 return) also does not combine with the salary. Both solutions protect against entering the 32% bracket but remove joint filing with a spouse and some reliefs. The ryczałt rate depends on the type of services.
Employment contract: non-compete and work for the same employer
The Labour Code does not prohibit an employee from running a business. The restriction may follow from a separate non-compete agreement, which requires written form. If such an agreement is in force, activity in the same industry as the employer, or even work for a competitor, may end in a claim for damages. Before registering the business it is worth reading the contract and regulations, including provisions on rights to created solutions.
A separate trap is providing services within the business to one's own employer. If an entrepreneur on the flat tax earns revenue from services to the current or former employer corresponding to work performed in the given year under an employment contract, they lose the right to the 19% rate for the whole year and must recalculate advances on the scale together with interest. Such an arrangement also draws the attention of ZUS and the tax office, and the risks of a contract resembling employment are discussed in the article on a B2B contract reclassified as employment.
Example: full-time vs half-time
Ms Marta works as an accountant and wants to run online courses. She expects about PLN 4,000 of revenue per month, i.e. PLN 48,000 per year, and chooses ryczałt.
- Variant A: full-time, salary PLN 7,000 gross. The salary exceeds the minimum wage, so from the business only the health contribution is paid. With revenue up to PLN 60,000 per year it is PLN 498.35 per month in 2026. On top of this comes ryczałt on revenue.
- Variant B: half-time, salary PLN 3,200 gross. The salary is lower than PLN 4,806, so the business is a mandatory title for social contributions. For the first 6 months the start-up relief helps, then for 24 months contributions from the preferential base (PLN 1,441.80 in 2026), and after that full social contributions with voluntary sickness and the Labour Fund and Solidarity Fund — which at the minimum base total PLN 1,926.76 per month, plus the health contribution.
The same course revenue gives a completely different result at the end of the month in each variant. When there is a small difference between the salary and the minimum wage threshold, it is sometimes better to negotiate a higher salary on the employment contract than to carry contributions from the business.
Checklist before registering the business
- Check whether the salary from the employment contract is at least PLN 4,806 gross per month in 2026 and whether it will not drop below that threshold.
- Estimate the business's revenue and costs, and then compare the scale, flat tax and ryczałt together with the salary.
- Read the employment contract and any non-compete agreement.
- Make sure the business will not provide services to the current employer.
- Register the activity in CEIDG and register for health insurance.
How Good Balance can help
We help plan a business run alongside a job: we compare forms of taxation taking the salary into account, check ZUS duties and register the firm. The scope of support is described on the sole proprietorship handling page, and we run current settlements as part of simplified accounting.