September 21 Deadline: Self-Employed Must Pay August ZUS Contributions and Tax Installments
Self-employed individuals and business owners have until September 21, 2026, to pay August ZUS social contributions and income tax installments. The deadline shifts due to the regular payment date falling on Sunday, September 20.
Self-employed workers, small business owners, and professionals operating in Poland must meet a critical payment deadline on September 21, 2026, for outstanding August obligations. This extension applies because the usual payment date—the 20th—fell on Sunday, September 20.
What Is Due:
- ZUS social contributions (pension, disability, accident insurance) for August 2026
- Health insurance contributions (NFZ/ubezpieczenie zdrowotne) for August
- Income tax installments (commonly referred to as "PIT-5" in practice, though the formal declaration no longer uses that form) for self-employed persons on the general tax scale or linear tax system
Kvartal instalments follow the same rule: for quarterly filers, the deadline for Q3 contributions is the 20th of the month following quarter end, or the next business day if the 20th falls on a weekend.
What this means for you: Mark September 21 on your calendar. Late payment incurs penalties and interest charges that compound daily. If you use an accountant or tax advisor, confirm they have submitted your documentation to ZUS on time; delays in filing documents do not excuse late payment of contributions. Online bank transfers and ZUS direct debit (if set up) are the safest methods to prove timely payment.
Sources
Independent app, not a government. General information, not advice. The official source:
