How to File PIT-37 in Poland — Step-by-Step Guide for 2026

PIT-37 is the most commonly filed tax return in Poland. It applies to individuals who receive income exclusively through tax withholding agents — employers, contract issuers, and pension authorities. If you work on an employment contract (umowa o pracę), civil law contract (umowa zlecenie), or contract for specific work (umowa o dzieło), and you do not run a business, PIT-37 is your form.

This guide walks you through the entire process — from confirming PIT-37 is the right form for you, through filing, to claiming every deduction you are entitled to.

Who Files PIT-37?

You file PIT-37 if you earned income in the previous tax year exclusively through withholding agents and did not operate a business. This includes:

• Employees on employment contracts (UoP) — the largest group
• Contractors on civil law contracts (umowa zlecenie) — where the issuer withholds tax
• People earning from contracts for specific work (umowa o dzieło)
• Retirees and pensioners — receiving benefits from ZUS or KRUS
• Recipients of social benefits — sickness, maternity, unemployment

When PIT-37 is NOT the right form:

• You run a business → PIT-36 or PIT-36L
• You have foreign income → PIT-36
• You have cryptocurrency income → PIT-38
• You sold real estate → PIT-39

Filing Deadline

The return for 2025 must be filed between February 15 and April 30, 2026. Missing the deadline can result in a fine — from a fixed penalty (up to PLN 6 750) to formal fiscal criminal proceedings.

Important: Since 2019, Poland operates the Twój e-PIT (Your e-PIT) service within the e-Tax Office system. The tax authority automatically prepares your return based on employer-submitted data (PIT-11). If you do nothing by April 30, the pre-filled return is automatically accepted — but you should review it and add applicable deductions.

Step 1: Gather Documents

Before you start, collect:

• PIT-11 from your employer(s) — received by end of February. This is the foundation — it contains your income, tax-deductible costs, and tax advances paid.
• PIT-8C — if you had capital gains income (though that goes on PIT-38)
• PIT-40A/11A — from ZUS, if you received social benefits
• Donation certificates — if you made charitable donations
• Documents supporting deductions — rehabilitation, thermal renovation, internet (if claiming for the first or second time)
• Public benefit organization (OPP) details — if you want to direct 1.5% of your tax

Step 2: Log Into the e-Tax Office

Go to e-urzadskarbowy.gov.pl and log in using:

• Trusted Profile (ePUAP) — the most common method
• e-ID card — ID card with electronic layer
• Online banking — login through your bank
• mObywatel app

After logging in, navigate to Twój e-PIT. The system will display your pre-filled return.

Step 3: Review the Pre-Filled Data

The pre-filled PIT-37 contains data from PIT-11 forms submitted by your employers. Check carefully:

• Personal data — name, address, PESEL (national ID number)
• Income and costs — verify amounts match your received PIT-11 forms
• Tax advances — total advances withheld by employers
• Filing method — individual or joint with spouse

If you had multiple employers, the system should aggregate all PIT-11 forms. Verify that all are included.

Step 4: Apply Tax Deductions

This is the most important step — proper deductions can yield a refund from several hundred to several thousand zloty.

Child tax credit (ulga prorodzinna)

• 1 child: PLN 1 112.04/year (if combined spousal income < PLN 112 000)
• 2 children: PLN 2 224.08/year
• 3 children: PLN 4 224.12/year (third child adds PLN 2 000.04)
• 4+ children: each additional — PLN 2 700/year

Rehabilitation deduction

Deduct expenses for rehabilitation purposes — medications (above PLN 100/month), equipment, car use (PLN 2 280 flat amount), rehabilitation stays. Applies to people with certified disability or those supporting such individuals.

Thermal renovation deduction

Up to PLN 53 000 deductible for thermal renovation of a single-family home — solar panels, heat pumps, insulation, window replacement.

Internet deduction

Maximum PLN 760/year — but only for 2 consecutive tax years (then it expires).

Charitable donations

Deductible donations to public benefit organizations, religious institutions, blood donation — up to 6% of income combined.

Social security and health insurance contributions — deducted automatically based on PIT-11 data.

Step 5: Designate 1.5% for a Public Benefit Organization

You can direct 1.5% of your tax due to a chosen public benefit organization (OPP). This costs you nothing — the money would otherwise go to the general budget. Enter the organization's KRS number and optionally a specific purpose.

Step 6: Review the Result and Submit

The system calculates:

• Tax due — how much you should have paid for the entire year
• Advances withheld — how much your employer already paid
• Overpayment or underpayment — the difference

If you have an overpayment — the tax office refunds it within 45 days (e-filing) or 3 months (paper filing). If there is an underpayment — you must pay the difference by April 30.

Submit the return by clicking "Accept and send." Download the UPO (Official Acknowledgment of Receipt) — this is your proof of filing.

Joint Filing with Spouse

If you are married and have joint property, you can file jointly. This is especially beneficial when one spouse earns significantly more — the progressive tax scale (12% up to PLN 120 000, 32% above) is calculated on half the combined income.

Example: One spouse earns PLN 180 000, the other PLN 40 000. Filing separately — the first spouse pays 32% on income above PLN 120 000. Filing jointly — combined income PLN 220 000 / 2 = PLN 110 000 per person — both fall within the first bracket. Savings: several thousand zloty.

Common Mistakes

1. Not reviewing Twój e-PIT — the system does not automatically add deductions requiring your declaration
2. Missing a PIT-11 from a second employer — if you changed jobs during the year
3. Not claiming the child tax credit — especially beneficial with joint filing
4. Skipping 1.5% for OPP — it is free money for your chosen organization
5. Not reporting an address change — your tax refund may be sent to the wrong address

How Freenance Helps with Financial Planning Around Tax Time

Filing PIT-37 is a good moment to take a bird's-eye view of your finances. Freenance will not fill out your tax return, but it helps you understand how your income, expenses, and savings translate into real financial independence. Your Financial Freedom Runway — how many months you could survive without working — is the metric that gives meaning to the whole exercise of taxes and saving.

FAQ

What happens if I miss the PIT-37 deadline?

If you do not file by April 30, the Twój e-PIT system automatically accepts the pre-filled version. You will not be penalized, but you may lose deductions that required manual entry. If no PIT-37 was prepared at all (e.g., no PIT-11 on file), you risk a fine of up to PLN 6 750 or formal fiscal criminal proceedings.

Can I file PIT-37 on paper?

Yes — you can still submit a paper PIT-37 at your tax office or mail it (the postmark date counts). However, e-filing is faster, and the tax refund arrives within 45 days instead of 3 months.

Does a student file PIT-37?

Yes, if they worked on an employment contract, civil law contract, or contract for specific work. Students under 26 benefit from the youth tax relief (zero PIT on income up to PLN 85 528/year), but they file PIT-37 normally — the system simply shows zero or minimal tax due.