What documents should you send your accountant every month in Poland?

Send your accountant every document from the month: the invoices you issued, the invoices and receipts for what you bought (foreign ones included), and the bank statement for every account the business uses. Add a short note on anything unusual. Most contracts ask for it by the 5th–10th of the next month. That gives your accountant time before the legal deadlines: the 15th for a company’s ZUS (social insurance) contributions, the 20th for income tax and a sole trader’s ZUS, and the 25th for VAT.

What to send each month

Whether you run a JDG (jednoosobowa działalność gospodarcza, a sole trader business) or a sp. z o.o. (a limited company), the core is the same.

Then add a short note on anything that changed during the month:

• A car you deduct fully: the mileage log (ewidencja przebiegu pojazdu).
• People: new contracts, hours, sick leave, anyone who joined or left.
• ZUS: preferential contributions ending, sick leave, a new job elsewhere.
• The business itself: a new address, bank account, PKD activity codes, VAT status, a suspension, a first foreign client or supplier.
• Unclear bank lines: one sentence each (“refund from Allegro”, “private, wrong card”).

By which day to send them

No law says when your documents must reach the office. Your contract does. The usual day is between the 5th and the 10th of the following month. That leaves your accountant about ten days to book everything before the dates fixed by law.

A sole trader’s documents go into the KPiR (podatkowa księga przychodów i rozchodów, the tax book of revenue and expenses), or into the revenue register if you pay ryczałt (the flat-rate tax on revenue).

If a sales invoice arrives after the 20th, it is already late for the book, even if you pay VAT quarterly.

When the 20th or the 25th falls on a Saturday, Sunday or public holiday, the deadline moves to the next working day. For the rest of 2026 that gives:

The full calendar is in our guide to tax and ZUS deadlines for 2026.

What your accountant already sees in KSeF

KSeF (Krajowy System e-Faktur) has changed much of this list. Since 1 February 2026 every business receives invoices through it, and since 1 April 2026 almost every business must issue its invoices to other businesses there.

Give your accountant a permission in KSeF and they can see the Polish invoices issued to your NIP, and the ones you issued, without you forwarding anything. You can name the whole office by its NIP, or one person, and choose a scope such as viewing invoices. Our KSeF guide explains how to grant it.

Three things to know:

• KSeF sends no notifications. Someone has to look. Ask your accountant whether they pull your invoices themselves, and whether that costs extra. One large online office charges a sole trader 50 PLN net (a company 150 PLN) when it downloads them for you.
• Your NIP must be on the invoice. Since 1 February 2026 a business buyer has to give its NIP to the seller. An invoice without it does not reach your KSeF account.
• KSeF knows an invoice exists, not what it was for. It cannot tell a business purchase from a private one, or show whether you paid.

What KSeF does not hold, so you still send it:

• Invoices from foreign suppliers. The Ministry of Finance’s FAQ is plain: KSeF is not for reporting purchases from abroad. See the invoices KSeF won’t collect.
• Till receipts. Until 31 December 2026 this includes receipts with your NIP up to 450 PLN and invoices a shop prints from its cash register.
• Invoices from small sellers. Sellers whose invoices to businesses total no more than 10,000 PLN a month, VAT included, may issue them outside KSeF until 31 December 2026.
• Invoices you issue to consumers, which do not have to go through KSeF.
• Bank statements and your notes.

From 1 January 2027 the 10,000 PLN relief ends and a receipt with your NIP stops counting as an invoice. More of your Polish costs will then arrive through KSeF. Foreign invoices and bank statements will not.

How to send them

Pick one channel, agree it with the office in writing, and use it every month.

Whichever you choose, give the files readable names, such as 2026-09-12 Adobe 24.60 EUR.pdf, and send the month in one go rather than in pieces. If your office works from photos of receipts, still keep the paper original in that month’s folder.

Komplet, our free Mac app, has a “Prepare for my accountant” button that builds one folder and a ZIP for the month: every document, the bank statements, and a Summary.pdf and Summary.csv your accountant can read. The month package guide shows how it works.

Before the first month, your accountant may also need permissions:

• KSeF: a permission granted in the KSeF Taxpayer App.
• UPL-1: lets them sign and send your tax returns electronically. It is free, filed in e-Urząd Skarbowy (the tax office’s online service) or on paper, and withdrawn with OPL-1.
• ZUS PEL: a power of attorney at ZUS, if they send your ZUS DRA.

What causes extra fees or late filings

Offices charge extra for late or missing documents. The price list of ifirma, a large online accounting office, shows the pattern (net, sole trader, checked in September 2026):

For a company the late-delivery charges at the same office are 160, 330 and 600 PLN. Your office’s list will differ, so read it.

The documents that cause most of the chasing:

• Foreign invoices never sent. They do not arrive by themselves. If you are VAT-exempt, services bought from abroad can also mean a VAT-9M return and Polish VAT to pay by the 25th: see why Google, Adobe or AWS may need VAT-UE registration.
• Bank payments with no document, especially card payments abroad.
• Private and business spending on one account, with nothing to tell them apart.
• Receipts without your NIP. A shop may not issue a business invoice later for a sale on a receipt that did not show your NIP.

Watch out: hiring an accountant does not move the responsibility. Under the Tax Ordinance the taxpayer is liable for their taxes with all their assets. If a return is wrong because a document was missing, the tax office comes to you.

One check before you send catches most gaps: every business line on the bank statement should have a document, and every document should have its payment. Our guide to matching payments to invoices walks through it.

What to do next

1. Ask your accountant for the exact day and channel in your contract, and write it in your calendar.
2. Give them a KSeF permission, and ask whether they pull your invoices or expect you to.
3. List every foreign supplier you pay and where each one’s invoices are downloaded.
4. On the 1st of each month, download the statements for every business account.
5. Tick each bank line against a document, add a note for the odd ones, and send the month in one go.