If you've designated a workspace in your home — a room or part of one — you can include a proportional share of the following expenses as deductible costs (KUP): Electricity — electric power bills, proportional to the office floor area. Gas and heating — in the same floor-area proportion. Internet — there's a special rule here (more in a separate section below). Administrative rent — fees paid to a housing cooperative or community. Property tax — decision from the municipality, proportionally. Water and sewage — if you use some water for business purposes (e.g. washing hands, cleaning the office). Mortgage interest — yes, this is possible. Confirmed by an individual interpretation from DKIS (Director of the Tax Chamber). Home insurance — proportional to the office floor area. The key rule: you deduct only the portion of the expense that corresponds to the office's share of the total floor area. There's no room for arbitrariness here — the ratio must be calculable and defensible during an audit.

Home office in a JDG — which housing costs you can deduct in Poland (2026)

Running a business from home: deducting electricity, internet, mortgage interest, renovation. Floor-area ratio, lump sum vs KPiR, pitfalls.

Running a JDG from home? You can deduct part of your housing costs — electricity, gas, internet, property tax, even mortgage interest. The short answer is: yes, but proportionally to the office floor area and only if you settle under the tax scale or flat tax.

On the lump sum, you cannot deduct any of these costs at all.

Below I break it down step by step — what exactly you can put in costs, how to calculate the ratio, and where the pitfalls are.

What you can deduct

If you've designated a workspace in your home — a room or part of one — you can include a proportional share of the following expenses as deductible costs (KUP):

Electricity — electric power bills, proportional to the office floor area.
Gas and heating — in the same floor-area proportion.
Internet — there's a special rule here (more in a separate section below).
Administrative rent — fees paid to a housing cooperative or community.
Property tax — decision from the municipality, proportionally.
Water and sewage — if you use some water for business purposes (e.g. washing hands, cleaning the office).
Mortgage interest — yes, this is possible. Confirmed by an individual interpretation from DKIS (Director of the Tax Chamber).
Home insurance — proportional to the office floor area.

The key rule: you deduct only the portion of the expense that corresponds to the office's share of the total floor area. There's no room for arbitrariness here — the ratio must be calculable and defensible during an audit.

How to calculate the ratio

The most commonly used and tax-office-accepted method is the floor-area ratio. You divide the office area by the total area of the home.

Numerical example

A home with a total area of 60 m². You dedicate 10 m² to the office.

10 m² / 60 m² = 0.1667 = 16.67%

The electricity bill for a given month is 200 zł.

200 zł × 16.67% = 33.33 zł

33 zł goes into business costs. The rest is a private expense.

The same ratio applies to gas, rent, property tax, insurance, and mortgage interest. You calculate it once — then apply it to all fixed expenses.

What if the office is part of a room?

You don't need a separate room. You can designate part of a room — for example, a desk and surrounding area of 4 m² in a 20 m² living room. Then the share is 4/60. What matters is that the space is genuinely used for business and can be pointed to.

Internet — the special rule

Internet is an exception in a good way. Instead of the floor-area ratio, you can use a time-based ratio — i.e. deduct the share of hours you use the connection for business.

Why is this more favorable? Because floor area doesn't reflect how intensively you use the connection. If you work at a computer 8 hours a day, the time-based ratio may come out significantly higher than 16%.

Example

Internet costs 50 zł/month. You work remotely 8 hours a day for 22 days a month. For private purposes you use the connection on average 4 hours a day after work.

Business time: 8 h × 22 days = 176 h
Private time: 4 h × 22 days = 88 h (+ weekends)

Business ratio:

176 / (176 + 88 + weekends) ≈ 45–55%

Instead of 16% from floor area, you can deduct approx. 50% of the internet bill. That's a real difference.

Note: you must be able to defend this calculation. Keep a record of how you count hours — the method doesn't have to be minute-accurate, but it must be logical and repeatable.

Lump sum — caution

On the lump sum, you cannot deduct any housing costs. The lump sum is a tax on revenue — without the right to deduct costs (KUP).

If you run your business on the lump sum (e.g. IT services at 12% or 8.5%), costs like electricity, internet, or interest simply don't exist in your settlement. Regardless of whether you work from home or an office.

This is one of the main reasons it's worth recalculating whether the lump sum truly pays off when you have significant fixed costs. Sometimes switching to the flat tax (19%) with the right to KUP results in a lower effective tax.

Depreciation of a home — ended since 2023

Since 2023, you can no longer depreciate residential buildings and premises used in business activity. This follows from Art. 22c sec. 2 of the PIT Act. This is a hard restriction — no exceptions.

What does this mean in practice?

You don't enter the home into the fixed assets register for depreciation.
You don't make depreciation write-offs on the property's value.
You don't deduct the "wear" of the home as a cost.

You can still deduct current operating costs (electricity, gas, internet, rent) — because these are not depreciation. But the building or premises itself is not subject to write-offs.

If you were depreciating a residential premises before 2023, the write-offs have ended. You cannot continue them or "finish" the remaining value.

Renovation vs improvement

This distinction has major tax significance.

Renovation = one-time cost

An ordinary renovation — painting walls, replacing damaged panels, fixing a faucet — is a one-time cost. You put it in the KPiR in the month the expense is incurred (proportional to office floor area if the renovation covers the entire home, or 100% if it covers only the office).

Example: painting the office for 1 500 zł (invoice, materials + labor) = 1 500 zł in costs that month.

Improvement = increase in fixed asset value

If the expense is an improvement — i.e. modernization, expansion, reconstruction, installation of something new that increases the property's value — then it increases the initial value of the fixed asset.

And here's the problem: since a residential premises cannot be depreciated (see section above), the improvement won't be settled through write-offs either. The expense "hangs" in the fixed asset value but doesn't generate costs.

When is an expense an improvement? When it significantly changes the property's features or value — e.g. adding a partition wall, installing a complete air conditioning system, upgrading the electrical installation to three-phase.

The line between renovation and improvement can be thin and depends on the scale and nature of the work. When in doubt, consult your accountant.

Office equipment

Equipment and furniture for the office are settled differently from housing costs.

Equipment used exclusively for business = 100% in costs

Desk, chair, computer, monitor, printer — if you use them only in business activity, you deduct 100% of the expense. No floor-area ratio, no splitting.

Computer for 4 000 zł = 4 000 zł in costs (or depreciation, if worth more than 10 000 zł — but this is rare for individual equipment).
Desk for 800 zł = 800 zł one-time in the KPiR.

Shared equipment = floor-area ratio

If something is used both privately and for business — for example a refrigerator, kitchen furniture, bathroom furniture — you deduct a portion proportional to the office floor area.

Refrigerator for 1 500 zł, home 60 m², office 10 m²:

1 500 zł × 16.67% = 250 zł

250 zł in costs. The rest is a private expense.

The logic is the same as for operating costs — the floor-area ratio determines the "business share" of jointly used assets.

Practical matters

Documentation

Every deductible cost must be documented — an invoice or receipt in your name (or the cooperative's, if it's rent). An electricity bill with two names (yours and your spouse's) — you deduct your share of the ratio.

Cooperative / community

If the home is in cooperative ownership or a cooperative right to a premises — you can still deduct costs. Ownership of the land is not a condition here. What matters is that you incur operating costs and use the premises in your business.

Spouse

If your spouse also runs a business or is on the lump sum — you split costs according to each person's share. You don't deduct the entire business portion if the other half also has a business in the same home.

No designated office

If you work "wherever" — sometimes on the couch, sometimes in the kitchen — you cannot deduct housing costs. You must have a designated, identifiable office space. It doesn't have to be a separate room, but it must be specifically defined.

Most common mistakes

Deducting on the lump sum — the lump sum doesn't allow any KUP, including housing costs.
Deducting 100% of electricity or gas — always a floor-area ratio, unless you have documented business-only usage.
Depreciating a home after 2023 — not allowed, Art. 22c sec. 2 PIT.
Booking improvements as renovation — if it's a modernization that increases value, it's not a one-time cost.
No designated workspace — "I work from home" isn't enough, there must be a specific space.
Too-high internet ratio without justification — if you deduct 90% of the bill, you must be able to defend it.

Summary

A home office is a real tax saving — but only if you do it correctly. The most important rules:

Tax scale or flat tax — yes, you deduct. Lump sum — no.
Floor-area ratio for most fixed costs.
Time-based ratio for internet — often more favorable.
No depreciation of a home since 2023.
Renovation = one-time cost; improvement = increase in value (and a problem with settlement).
Business equipment = 100%, shared equipment = ratio.

Sources

Based on Polish tax regulations.

Need help sorting out your home office costs?

Oxyok handles JDG accounting — including proper settlement of housing costs, ratios, and equipment registers. Accounting from 49 zł + VAT per month.

Email Paweł or see Oxyok accounting.

This material is of a general nature. Your individual ratio and expense classification (renovation vs improvement) is worth discussing with your accountant.