Taxation

PIT-36 or PIT-37
— Which Form for 2025?

April 7, 2026 10 min read Piotr Nowak

Every year, Polish taxpayers must answer: PIT-36 or PIT-37? The choice depends on whether you're self-employed or an employee, whether you had other income, and whether you want to file jointly with a spouse. In this guide, I clarify the differences, explain who files which form, and help you understand the deadline and key sections.

PIT-36 vs. PIT-37: Key Differences

Feature PIT-36 PIT-37
Who files Self-employed, business income Employees, wages only
Joint filing Yes (PIT-36S) Possible under conditions
Other income sections Yes (rental, capital gains, etc.) Limited sections
Business deductions Yes, detailed No business sections
Complexity Complex, many sections Simple, wage-focused

Who Files PIT-36?

  • Self-employed and entrepreneurs (all tax forms)
  • Freelancers and contractors with business income
  • Farmers
  • Anyone with income from rental property
  • Anyone with capital gains or investment income
  • Anyone with multiple income sources

Who Files PIT-37?

  • Employees earning only employment wages
  • No self-employment income
  • No rental income
  • No investment or capital gains
  • If other minor income, still may use PIT-37 (with some conditions)

PIT-36 Key Sections

Part I: Personal Details and Income Sources

Identifies you, filing status, and which income sources apply.

Part II: Business Income

Revenue and deductions if you're self-employed or have business income from KPiR, flat rate, or linear tax.

Part III: Other Income

Rental income, agricultural income, capital gains, foreign income.

Part IV: Tax Calculation

Total income, deductions, tax thresholds, final tax owed or refund.

PIT-37 Key Sections

Part A: Employment Income

Wages and salary from employer(s).

Part B: Other Income

Limited sections for minor income (interest, dividends).

Part C: Tax Calculation

Tax computed from total income with standard deductions and reliefs.

Joint Spouse Filing

PIT-36S (Joint PIT-36):

  • Both spouses file together on one form
  • Both must have business income or other qualifying income
  • Allows income splitting and potential tax optimization
  • Both signatures required

Can two PIT-37 filers file jointly?

Generally no. Two employees with only wages file separate PIT-37 forms. However, if one spouse has other income (rental, capital gains), they may file PIT-36 jointly.

Filing Deadline and Extensions

Standard deadline: April 30, 2026

  • Electronic (e-PIT): Available from February 15, 2026
  • Paper: Must arrive at tax office by April 30

Extended deadline: May 31, 2026

  • If filing through a tax advisor or accounting firm
  • Requires proof of professional assistance

Common Filing Mistakes

  • Filing wrong form: Self-employed filing PIT-37 is rejected
  • Missing deductions: Forgetting eligible business or personal deductions
  • Calculation errors: Arithmetic mistakes in tax computation
  • Missing spouse details: Joint filing without complete spouse information
  • Late filing: Missing April 30 deadline incurs penalties

Frequently Asked Questions

I have a part-time business and main employment. Which form?

PIT-36. Any business income requires PIT-36, regardless of whether you're primarily employed.

Can I amend my return after filing?

Yes. File a correction form (PIT-36 albo PIT-37 KO) within 3 years of the original filing date.

What if I miss the April 30 deadline?

Late filing penalties apply: 40 PLN per day (first 30 days), then 100 PLN per day. File as soon as possible.

Piotr Nowak
Tax Advisor — PIT Filing Expert

Piotr has 18 years of experience helping individuals and entrepreneurs navigate PIT filings and optimize their tax returns.

Expertise: PIT, CIT, tax filings, deductions
Article reviewed by: Anna Wiśniewska, tax advisor (April 7, 2026)