Changes in tax filings and how accounting is organised in 2026

2026 brings a series of material changes in Polish tax and accounting law. This article covers the most important of them and how they affect the daily work of a business owner and an accounting firm.

1. Mandatory KSeF — the key dates

KSeF (the National e-Invoice System) becomes mandatory for all VAT taxpayers. The rollout is staged:

• Large enterprises — obligation from 1 February 2026
• Medium and small enterprises — obligation from 1 April 2026
• Micro-enterprises — from 1 July 2026

2. Changes in CIT and PIT

The tax-act amendments introduce a number of changes to the taxation of business income. The most important concern deductible costs and depreciation of fixed assets.

3. Revision of the Accounting Act

The amended Accounting Act aligns Polish rules with EU directives, including a sustainability-reporting obligation for larger entities.

4. Changes in ZUS contributions

New contribution thresholds for sole traders apply from 2026. Entrepreneurs using the start-up relief or “mały ZUS plus” should check whether they still qualify.

Summary

2026 is a dense year of legislative change. We invite you to contact our experts, who will help adapt your business to the new requirements.