14 November 2025

Seniority – beneficial changes in the calculation method

Changes in the calculation of seniority – good changes for entrepreneurs and contractors

Seniority. Amendments to the Labor Code, recently signed by the President, regarding the calculation of seniority have been published in the Journal of Laws. These changes will take effect in 2026. From that point on, seniority will not only be based on employment under a traditional employment contract; it will also include time spent in business activities and contract work.

Seniority – what does it look like now?

Under the current law, seniority includes work performed under an employment relationship and periods of education (e.g., studies). The amount of seniority accrued will determine additional employee entitlements (e.g., the number of vacation days – 26 days instead of the standard 20 days, the right to parental leave).

As a rule, if an employee has been employed for less than 10 years, they will be entitled to 20 days of vacation leave, while if they have been employed for more than 10 years, they will be entitled to 26 days of vacation leave.

Changes from 2026

Starting in 2026, the calculation of length of service will include not only employment under an employment contract but also additional forms of employment.

• periods of conducting non-agricultural business activity, periods of cooperation with a person running a business,
• period of employment under a mandate contract,
• period of performing agency contracts,
• period of performing service contracts,
• period of suspending business activity for the purpose of providing personal childcare.

Periods of additional employment must be verified with certificates from ZUS (Social Insurance Institution). You are required to present the appropriate documents that confirm your employment. The deadline for submitting proof of your length of service is 24 months from the date the Act comes into effect, which will be January 1, 2026.

Seniority – key dates

The regulations provide for two key effective dates:

• From January 1st, 2026, the regulations will apply to public sector employers.
• From May 1st, 2026 (i.e., six months from the date of publication of the Act in the Journal of Laws) – for private sector employers.