How to calculate PIT in Poland in 2026: step-by-step guide

From February 15 to April 30, 2026, employees in Poland submit their annual PIT tax return for the previous tax year. The easiest way to calculate it is the official Twój e-PIT service in the e-Tax Office. The system retrieves data from employers and calculates the tax automatically. You need to verify the information, supplement it if necessary, and submit the declaration. Important deadline: April 30. Until this date, you can verify, modify, or confirm your declaration in Twój e-PIT.

Who this guide is for

In this article, we explain how PIT is calculated in Poland in 2026 for different categories of taxpayers: for employees under employment contracts, for entrepreneurs on B2B, and in cases where the declaration is prepared by an accountant.

PIT calculation for employees under umowa o pracę and umowa zlecenie

Step 1. Understand which PIT you are submitting Most often, employees under umowa o pracę and umowa zlecenie submit a PIT-37 declaration. In most cases, it is prepared automatically by the Twój e-PIT service.

Step 2. Prepare documents and data Before logging into the service, prepare:

• PESEL or NIP;
• information from the employer (most often PIT-11);
• bank account number for tax refund, if there is an overpayment.

PIT-11 is a form prepared by the employer. It contains information about income, advance tax payments, and social contributions.

Step 3. Log in to Twój e-PIT Go to the official website podatki.gov.pl and open the Twój e-PIT service. Then log in to the e-Tax Office and open the section with your declaration.

Step 4. Check key figures In the declaration, check:

• Przychód – income;
• Koszty uzyskania przychodu – costs;
• Dochód – taxable income;
• Zaliczka na podatek – PIT advance paid during the year.

These data are usually transferred from PIT-11.

Step 5. Add what is missing in the automatic version Twój e-PIT is often correct “by default”. However, sometimes the data needs to be supplemented. For example:

• add tax reliefs if you are entitled to them;
• provide the current bank account number for refund;
• add other income if applicable.

After making changes, the system recalculates the result automatically.

Step 6. Check the calculation result After verifying the data, you will see one of the following:

• nadpłata – overpayment, the tax will be refunded;
• do zapłaty – amount to be paid.

This is the final PIT calculation result in Poland.

Step 7. Confirm and submit the declaration After verification, confirm and submit the declaration in Twój e-PIT. This must be done by April 30. If PIT-37 or PIT-38 is submitted and no changes are made, the system may accept the declaration automatically after the deadline. However, it is better to verify and confirm it manually.

Step 8. Download submission confirmation (UPO) After submission, be sure to download UPO. This is the official confirmation that the declaration has been accepted by the tax office. Common mistakes that lead to incorrect PIT calculation:

• data from PIT-11 not verified;
• tax relief not added;
• current bank account not provided;
• UPO confirmation not saved.

PIT calculation for B2B entrepreneurs

If you work in Poland under B2B, you are an entrepreneur and are responsible for your tax calculations. In this case, PIT is not generated automatically as it is for employees.

Where to get data for B2B PIT calculation

For the annual declaration, the entrepreneur uses their own accounting data, in particular:

• income from issued invoices (faktury);
• business expenses, if allowed under your taxation form;
• information on advance tax payments made;
• data on ZUS contributions (social and health).

These data are collected throughout the year in accounting or accounting software.

Where and how PIT is submitted for B2B

The annual PIT declaration is submitted via the e-Tax Office on podatki.gov.pl. Unlike employees, the entrepreneur:

• independently chooses the declaration form (PIT-36, PIT-36L, or PIT-28);
• enters all data independently or provides it to an accountant;
• submits the declaration online or through an authorized person.

The Twój e-PIT service usually does not automatically fill in B2B declarations. It can only be used as a submission channel, not as a ready calculation.

How the calculation looks in practice

The entrepreneur sums up income for the year, subtracts expenses (if applicable), considers paid advances and contributions. Based on this, it is determined whether there is an overpayment or an amount to be paid. This calculation must be completed before submitting the annual declaration.

Important to know

In B2B, responsibility for the correctness of the calculation always lies with the entrepreneur. That is why most entrepreneurs use the services of an accountant or accounting service.

PIT calculation through an accountant: how it works in practice

If you use an accountant, the calculation follows a similar logic but with professional support. This is a common solution for B2B entrepreneurs and for people with multiple sources of income.

What data should be provided to the accountant

For PIT calculation, the accountant needs:

• income documents (e.g. PIT-11 or invoices);
• information about expenses, if applicable;
• data on advance tax payments;
• information on ZUS contributions (social and health);
• data on tax reliefs, if applicable.

The accountant collects this data, verifies it, and prepares the calculation.

How the accountant calculates PIT

The accountant:

1. sums all income for the year;
2. calculates expenses according to the taxation form;
3. verifies advance payments;
4. applies tax reliefs;
5. determines whether there is an overpayment or amount due.

Based on this, the accountant prepares the annual PIT declaration in the appropriate form.

How the declaration is submitted The completed declaration is handled by the accountant as follows:

• submits it on behalf of the client (based on authorization);
• or provides it to the taxpayer for verification and approval.

Submission is carried out electronically via the e-Tax Office.

Important to remember

Even if the declaration is prepared and submitted by an accountant, legal responsibility remains with the taxpayer. Therefore, before submission, it is important to carefully verify all data and keep the submission confirmation (UPO).

Advice from Gremi Personal

To correctly calculate PIT in Poland and avoid mistakes, keep all documents from your employer, especially PIT-11. Always verify the data in Twój e-PIT or in the declaration prepared by an accountant and do not postpone submission until the last day. This will help you receive a tax refund faster or pay any due amount on time without penalties.