Year-end brings the entrepreneur a few hard obligations (physical inventory or stocktaking on 31 December, remitter's returns in January, possible change of taxation form by 20 February) and several decisions worth taking already in December. At the turn of 2026 and 2027, two one-off topics arise: the end of the transitional period for the old PKD codes and the KSeF obligation for the smallest firms. We have gathered them below in date order.
December: review of limits before year-end close
Many preferences for the coming year depend on the current year's revenue. Before 31 December it is worth checking in the accounts which side of each threshold the firm will land on:
| Threshold | Value | What depends on it |
|---|---|---|
| Turnover-based VAT exemption | PLN 240,000 of sales | whether in 2027 the firm can still operate without VAT |
| Mały ZUS Plus (Small ZUS Plus) | PLN 120,000 of revenue | right to social contributions calculated on income in 2027 |
| Ryczałt on recorded revenue | EUR 2 million of revenue | whether ryczałt can be chosen or kept for 2027 |
| Small CIT taxpayer | EUR 2 million of revenue | the company's right to the 9% rate |
The euro limit for ryczałt is translated at the average NBP rate from the first working day of October of the previous year, so the amount in zloty for 2027 can be set as early as autumn 2026.
December is also a good moment to decide on larger purchases. An expense incurred before year-end will only reduce the 2026 income if it is genuinely connected with the business and properly documented. Buying "as stock" solely to cut the tax rarely pays off, because more is actually spent than saved.
Two one-off topics at the end of 2026
PKD 2025 codes in CEIDG and KRS
Firms registered before PKD 2025 came into force may use the old codes no later than 31 December 2026. At the next change of entry, it is worth updating the codes, and if no change is planned, checking how the register will carry out the reclassification. Guidance is given in the article How to choose PKD codes.
KSeF for the smallest firms from 1 January 2027
From 1 April 2026 the National e-Invoicing System has been mandatory for most entrepreneurs. Firms whose invoiced sales do not exceed PLN 10,000 per month enjoy deferral until 1 January 2027. Before that date, you need to grant KSeF authorisations (to yourself, employees or the accounting office) and choose a tool for issuing invoices.
31 December: physical inventory or stocktaking
An entrepreneur keeping a KPiR (tax book of revenue and expenditure) draws up at the end of the tax year a physical inventory of goods, materials, semi-finished products, work in progress, finished goods, rejects and waste, and then enters it in the book. The inventory of 31 December also replaces the opening inventory of 1 January of the following year.
- The inventory covers stocks, not fixed assets or equipment (laptop, car, furniture).
- The sheet must contain, among others, the firm's data, the date, numbered items, quantity, price and value, and the signatures of the persons who carried out the inventory.
- A service provider without stocks (e.g. a programmer on general rules or flat tax) also draws it up — with value of zero.
- On ryczałt an annual physical inventory is not drawn up, because this duty follows from the rules on the KPiR, which ryczałt taxpayers do not keep.
Companies and other entities keeping books of account carry out a stocktaking on the last day of the financial year under the rules of the Accounting Act: a count of cash and stock, confirmation of account and receivable balances, verification of the remaining items.
January: returns and information for the previous year
- By the end of January a firm employing staff or mandate contractors sends the tax office the remitter's annual returns and PIT-11 information on each person's income. The employee or mandate contractor must receive their information by the end of February. In 2027 both dates (31 January and 28 February) fall on a Sunday, so under Article 12 § 5 of the Tax Ordinance the deadlines move to 1 February and 1 March.
- By 31 January an entrepreneur who wants to use Mały ZUS Plus from 2027 files the appropriate notification in ZUS. A delay means waiting for the next year.
- By 20 January is the usual deadline for payment of ZUS contributions for December by sole proprietorships (sp. z o.o. as legal persons pay by the 15th day).
By 20 February: form of taxation for the new year
The form of taxation rolls over automatically to the next year. Anyone wishing to change it (e.g. from general rules to flat tax or ryczałt) files a declaration no later than the 20th day of the month following the month of the first revenue in the new year. With revenue in January, the deadline falls on 20 February (in 2027 that is a Saturday, so the last day will be Monday 22 February); with the first revenue only in December — by year-end. The change is reported most easily through CEIDG.
The decision is best prepared in December, on the basis of the 11-month results and plans for the coming year. Details and a comparison of options are given in the article How to change the form of taxation.
Further spring deadlines
- 31 March — a company with a calendar year files the CIT-8 return and should have the financial statements drawn up.
- 15 February – 30 April — sole proprietorships file their annual PIT return for 2026 (returns filed before 15 February are deemed filed on 15 February).
- Spring — annual settlement of the health contribution with ZUS: an overpayment is refunded, and an underpayment must be topped up.
December 2026 checklist
- Check revenue against the VAT, Mały ZUS Plus, ryczałt and CIT limits.
- Collect all 2026 cost invoices and sort out missing documents.
- Reconcile the state of settlements and fixed assets with the accountant.
- Plan the physical inventory or stocktaking for 31 December.
- Update PKD codes if the register still shows old ones.
- Prepare access to KSeF if the firm uses the deferral until 2027.
- Calculate the taxation-form options for 2027.
How Good Balance can help
We guide our clients through the year-end close: we check the limits, prepare the physical inventory and annual returns, and as part of accounting advisory we calculate which form of taxation will be most favourable in 2027. Current accounting of sole proprietorships we provide as part of simplified accounting.