The 100 000 zł car limit in 2026: what an accounting office checks before closing the year

The Limit Changed in January. The Posting Schemes Didn't.

Since 1 January 2026 the limits for passenger cars have three tiers instead of two. A combustion car emitting 50 g CO2/km or more can go into costs up to 100 000 zł. Below 50 g it keeps 150 000 zł, and electric and hydrogen cars keep 225 000 zł. The change was enacted in December 2021, so nobody can say it came as a surprise.

What did catch offices out is something smaller. A lease signed in 2023 or 2024 got a recurring posting set up when the first invoice came in: "capital part times 74.74%, the rest in full". That scheme has been running every month since, and nothing in the accounting system asks whether the proportion is still right. In a lot of offices it isn't.

This is a year-end check, not news. Ten months of 2026 are booked. The question for November is which cars were booked at the wrong limit, and how much that adds up to before the annual returns.

Who Keeps the Old Limit and Who Doesn't

The transitional rule is art. 30 of the act of 2 December 2021 amending the electromobility act. It keeps the old rules for vehicles entered in the taxpayer's fixed-asset register before the change took effect. The date the lease was signed doesn't count, and neither does the invoice date. What counts is the register.

That gives a simple split:

• Car owned by the client, entered in the register by 31 December 2025. Old limit (150 000 zł, or 225 000 zł for electric) for the rest of its depreciation. Nothing changes.
• Finance lease where the client entered the car in its own register by 31 December 2025. Same: protected.
• Operating lease or rental signed before 2026. Not protected. The car was never in the client's register, so the new limit applies to every instalment from January 2026.
• Anything entered in the register in 2026. New limit, including a car bought out from a lease this year. If the buyout value is depreciated, it's measured against 100 000 zł, not 150 000 zł.

The operating-lease point is the one that hurts, and it's no longer a matter of opinion. In its reply to interpellation 13926 of 15 December 2025, the Ministry of Finance wrote that the 100 000 zł limit "will apply to lease and rental contracts concluded before 1 January 2026" where the contract didn't allow the car to be entered in the register. It also said it isn't working on raising the limit. A KIS interpretation of 9 January 2026 (0115-KDIT3.4011.890.2025.1.DP) took the same view. Installments booked under the old rules up to December 2025 stay as they were.

One Lease, Two Proportions

A sole trader on the flat tax took a combustion car on an operating lease in 2024: 180 000 zł net, 132 g CO2/km, used for business and privately, so half the VAT is deducted. The value for the limit is the net price plus the VAT that wasn't deducted: 180 000 + 20 700 = 200 700 zł.

• Old proportion: 150 000 / 200 700 = 74.74%
• New proportion: 100 000 / 200 700 = 49.83%

Say the capital part of each monthly instalment is 2 600 zł. At the old proportion 1 943.20 zł goes into costs. At the new one, 1 295.47 zł. That's 647.73 zł a month of costs that shouldn't be there, or 7 773 zł over 2026.

Just the tax: at 19% flat PIT that's about 1 477 zł of tax underpaid for the year, or about 700 zł for a small company at 9% CIT. The health contribution on the flat tax moves by about 380 zł on top. For a mixed-use car the 75% rule for running costs still applies on top of all this. I've left it out so you can see the effect of the limit on its own.

1 477 zł isn't dramatic for one car. But an office with 120 business clients usually has 15 to 25 leased cars, and every month of underpaid advances carries interest. Finding them in November and correcting the next advance is cheaper than finding them in April.

The owned-car version: a car worth 160 000 zł (net plus non-deductible VAT), entered in the register in April 2026, 20% a year. Depreciation starts the month after entry, so May to December is 8 months, 21 333 zł in total. With the 100 000 zł limit, 100/160 of that is deductible: 13 333 zł. If someone applied 150 000 zł out of habit, 20 000 zł went into costs, so 6 667 zł too much.

Three Things That Get Mixed Up

AC insurance didn't change. AC and GAP premiums are still deductible in the proportion of 150 000 zł to the value used for the policy, whatever the emissions. So the same leased car has instalments limited by 100 000 zł and the AC premium limited by 150 000 zł. A posting scheme that applies one proportion to both is wrong in one direction or the other.

The 50 g line is documented, not guessed. The figure comes from the vehicle's homologation, as shown in the registration certificate (or the certificate of conformity, COC), not from the dealer's brochure. Plug-in hybrids sit around the line: the same model can come in under 50 g in one version and over it in another, depending on the variant and equipment in the homologation. If the office has no document showing less than 50 g, the safe assumption is 100 000 zł, because the burden of proof is on the taxpayer.

The limit is not a deferred-tax item. The part above the limit never becomes a cost, so for clients on full books it's a permanent difference. It doesn't belong in the register of temporary differences. It does belong on the right tax marker: in the JPK_CIT and JPK_KR_PD files the non-deductible part of car costs needs to land on accounts marked as non-deductible, and a 2026 change in the proportion means the split between the two accounts changed too.

How Many Cars and Where the Data Sits

Checking one car takes five minutes if everything is in one place. It rarely is. The register entry date is in the fixed-asset module. The lease type is in the contract, which is usually a PDF in the client's folder. The proportion actually booked is in the recurring document or posting scheme in Optima, enova365 or Symfonia. The emission figure is in a scan of the registration certificate, if the office has one at all.

For 20 cars that's an afternoon nobody has in November, so the check gets pushed to the annual return. By then the advances have been underpaid for twelve months and the correction is a conversation with an unhappy client.

What usually turns up:

• Recurring postings still at the 2024 proportion. The most common one by far.
• One proportion for instalments and AC. Usually 150 000 zł for both, sometimes 100 000 zł for both.
• Buyouts entered in 2026 at the old limit, because the car "had always been 150 000".
• PHEVs with no emission document. Booked at 150 000 zł on the client's word.

What the Agent Prepares

An agent with read access to the office's data can build the car list as part of the month-end close the office already runs:

• Reads the fixed-asset register for each client and pulls every passenger car with its entry date, initial value and depreciation rate.
• Reads the lease and rental contracts (from the documents and from the recurring lessor invoices) and classifies each as operating, finance or rental, with the date signed.
• Reads the emission figure from the registration certificate or COC scan, and flags cars where there isn't one.
• Works out the right limit for each car under art. 30 and the 2026 tiers, and compares it with the proportion actually booked in 2026, separately for instalments or depreciation and for AC.
• Writes one line per car: "operating lease 2024, 132 g, booked 74.74%, should be 49.83%, 6 477 zł too much in costs January–October" or "owned since 2023, old limit correct, nothing to do".

The agent doesn't post corrections and doesn't change the posting schemes. The accountant reviews the list, fixes the schemes and decides how to correct the advances. That part has to be a person, because some of these calls depend on documents only the client has.

One Thing to Do This Week

Pull the list of recurring lessor invoices across your clients for October. For each one, check the proportion in the posting. If it's 150 000 divided by something and the car is a combustion model on an operating lease, the client needs a correction before the November advance.

If you'd like to see this list built from your own clients' registers, contracts and postings, write to me. I'll take one month of real data and show you which cars the agent flags and why.