Unauthorised construction can result in works being halted and proceedings before the building supervision authority, and not every irregularity follows the same removal procedure. Before taking any steps, compare the actual structure with the documentation you hold: check the permit, notification, design and subsequent changes. Establish the scope of the breach and the date the works were completed, as these determine the correct procedure. Remember that the absence of a document from your home file does not prove it was never issued – the records may be held at the office. This determination can matter more than preparing a new cost estimate. This guide describes Polish law as at 1 November 2026.

In 2026 the scope of building simplifications and supervision procedures changed, but this does not mean freedom to build without a design. Investors should first check whether the planned works qualify for a specific exemption and what conditions must be met. It is essential to identify the correct provision and its commencement date, because some changes from the act adopted at the end of 2025 have applied since 7 January 2026, while other regulations have separate dates, including 20 September 2026. Decisions should not be based on the headline 'new building law' alone. This guide describes Polish law as at 1 November 2026.