More and more sole traders no longer rent a separate office — the work happens at a desk in the living room or in a dedicated part of the house. That is legal and cheap, but it raises three separate issues: the address in the CEIDG register, tax-deductible costs, and property tax. Each follows its own rules, and mistakes usually surface only during an audit or when the municipal tax decision arrives.
A business address in your home — what you report to CEIDG
What you report to CEIDG is, first of all, the service address, that is the place where you receive correspondence concerning your business. If the business has a fixed place of activity, you also report that address — and it may be your flat. If you mostly work at clients' premises or your work is mobile, you can tick "no fixed place of business activity" in the application; the service address then remains the only address in the entry.
For every property whose address you report you must hold legal title: ownership or co-ownership, a cooperative ownership right to the premises, perpetual usufruct, a lease, a tenancy or a loan for use. The document is not attached to the application, but the minister keeping the register may request it. If you fail to produce the title within 7 days of the request and do not amend the entry, you may be struck off the CEIDG. Changing the address in the register itself is free of charge.
When home expenses count as tax-deductible costs
According to tax authority interpretations, expenses for maintaining and running a flat may be deducted in full only where the premises — as a whole or a separated room within them — serve exclusively the business activity and at the same time do not serve personal purposes. A room that holds your desk during the day and your child at night does not meet that condition.
Where a room is used privately and additionally in the business, you must determine which part actually serves the business and deduct the expenses in that proportion. This covers the typical items: rent or service charges, electricity, water and heating. This approach is safer than trying to deduct everything and is what sole traders most often do in practice.
How to establish and document the proportion
The regulations do not impose a single method of calculation. In practice the usual measure is the ratio of the floor area used for business to the total floor area of the flat. If you use 12 sq m of a 60 sq m flat for your business, the proportion is 20% — and that is the share of utility bills and rent you deduct.
It is worth documenting that proportion before the authorities ask: a short note describing which room is used for business and to what extent, a simple floor plan or the measurements, and all invoices kept on file. Having your business address at home does not by itself entitle you to deduct the whole rent — the tax authority looks at how the premises are actually used, and the burden of proof lies with the entrepreneur.
Property tax — the trap that is easy to overlook
Property tax is set by the municipal council, but it may not exceed the maximum rates announced by the Minister of Finance. For 2026, under the announcement of 1 August 2025 (M.P. 2025 item 726), the maximum rate for residential buildings or parts thereof is PLN 1.25 per sq m of usable floor area, while for buildings or parts thereof connected with business activity — and for residential buildings occupied for such activity — it is PLN 35.53 per sq m. The difference is therefore substantial.
The key phrase is "occupied for the conduct of business activity". If a room also serves residential purposes, it can hardly be said to be occupied for the business. If, however, the room has been set aside solely for the business — for example a consulting room with its own entrance where you receive clients — the municipality may apply the higher rate to that floor area. An individual reports a change in the use of the property on form IN-1 within 14 days of the tax obligation arising. The tax is paid on the basis of a decision of the municipal authority in four instalments: by 15 March, 15 May, 15 September and 15 November; where the annual amount does not exceed PLN 100, it is payable in full by the first instalment date.
You cannot depreciate a flat
If you own the flat, do not count on depreciation write-offs. Under Article 22c of the Polish PIT Act, residential buildings, residential premises constituting separate property, the cooperative ownership right to residential premises and the right to a single-family house in a housing cooperative are not subject to depreciation — including where they serve business activity. This is what distinguishes a flat from commercial premises. Current running costs, in the established proportion, remain deductible.
Someone else's flat: the owner's consent and loan for use
If you want to run your business from a rented flat, you need the owner's consent. Indicating premises without legal title or without consent can lead not only to removal from the CEIDG, but also to problems with VAT registration and to expenses incurred on those premises being disallowed.
A separate question is the free-of-charge use of premises. Where they are made available by a close family member — persons in tax groups I and II under the Inheritance and Gift Tax Act, including a spouse, children, parents, siblings, parents-in-law, a son-in-law or daughter-in-law — no additional tax obligations arise. If, however, an unrelated person lends you the premises, the saving is treated as business revenue: you must estimate the market rental value and tax it.