Change your AB's preliminary tax when profit changes

You’ve closed October in the books and can see this year will be much better than last year. Or worse. Yet the same amount leaves the tax account every month, because that amount isn’t based on this year. It’s based on what happened a year and a half ago.

The amount you pay is built on old numbers

Unless you’ve filed your own estimate, Skatteverket (the Swedish Tax Agency) sets your company’s debiterad preliminärskatt, the assessed preliminary tax, using a formula. The main rule in the Tax Procedure Act, chapter 55 section 3 is 110 percent of the final tax in the latest decision. If that final tax ended up lower than the preliminary tax first assessed, 105 percent is used instead.

The amount is split into equal parts and is normally due on the 12th of each month. The formula works as long as the business runs roughly as before. When it doesn’t, it’s wrong in one direction or the other.

A worked example with a good year

Say your AB uses the calendar year as its financial year and made a taxable profit of SEK 400,000 in 2025. With corporate tax at 20.6 percent the tax is SEK 82,400. The formula for 2026 is 110 percent, so SEK 90,640, or about SEK 7,553 a month.

Now 2026 looks like landing at SEK 900,000. That means tax of SEK 185,400. You’ve paid SEK 75,530 through October and are SEK 109,870 behind. If you file a new estimate now, Skatteverket recalculates and the rest lands on November and December. The exact amount is in the new decision.

When you’re required to change it

You can change it whenever you like, but sometimes you have to. According to Skatteverket you must file a new preliminär inkomstdeklaration, a preliminary income tax return, if the final tax is expected to exceed the preliminary tax and the gap is about 30 percent and at least one prisbasbelopp, the price base amount. The price base amount for 2026 is SEK 59,200.

In the example the gap is SEK 94,760, more than half the expected tax. No doubt there. If you’re close to the threshold, change it anyway. It costs nothing and spares you a surprise on the tax account.

How to make the change

Use the e-service Preliminär inkomstdeklaration and log in as the authorised signatory or a representative. Without Swedish e-ID there’s the paper form SKV 4313 for legal entities. What you need is an honest forecast of the year’s taxable profit, not just the bookkeeping result so far. Think through three things before you submit.

• Salary to yourself before year end lowers the company’s profit, so decide on it first.
• A planned allocation to a periodiseringsfond, a tax allocation reserve, or large purchases in December also affect the figure.
• Non-deductible costs, such as entertainment above the allowed level, must be added back.

Until the new decision arrives you keep paying under the old one. You can file new estimates several times, up to six months after the end of the financial year.

If the year goes worse

Flip the example. Profit ends at SEK 150,000 and tax at SEK 30,900, but you’ve already paid SEK 75,530. Then you ask for the preliminary tax to be reduced. A limited company can’t get an early refund of assessed preliminary tax, but once the decision is lowered the reduced part can be paid back. The money does more good in the company than on the tax account.

An extra payment is the alternative

If you’d rather not raise the monthly amount, you can make an extra payment to the tax account instead. For financial years ending September to December 2026, Skatteverket’s table says amounts above SEK 30,000 must be credited by 12 February 2027. Up to SEK 30,000 can wait until 3 May 2027.

Miss those dates and cost interest runs. The low cost interest rate has been 2.5 percent, but it can change, so check the current rate. The interest isn’t deductible. I prefer raising the preliminary tax, because then the debt is gone by year end and you can’t forget about February.

Don’t forget next year

The formula has a floor. It can’t go below the most recently assessed preliminary tax, under chapter 55 section 3. If 2026 was a one-off year with a big deal, the 2027 assessment may end up high. In that case, file a new estimate in January as soon as the first decision arrives.

Do this this week: decide your own salary for November and December, work out the full-year profit and enter the estimate in the e-service. Then the new decision has time to change the payment due on 12 December.