Advance tax for sole proprietorships: deadlines in 2026

Advance tax for a sole proprietorship is paid in the same year that you earn the money. Report your expected profit in your tax deduction card, set money aside regularly and normally pay on 15 March, 15 June, 15 September and 15 December.

What is advance tax for a sole proprietorship?

Advance tax is the tax that you, as the owner of a sole proprietorship, pay yourself during the year. ENK means sole proprietorship. No employer deducts this tax from your income.

You have one tax deduction card that applies both to you privately and to the business. Skatteetaten therefore calculates the tax based on your entire financial situation. This may include:

• expected profit in the business
• salary from another job
• sickness benefit or parental benefit as a self-employed person
• assets and debt
• other income and deductions

If you have just started, you can first read SamfunnPrep’s guide on registering a sole proprietorship. Registration does not automatically create the correct advance tax. You must report the expected profit yourself.

How do you calculate expected profit?

Profit is the income you expect, minus the costs you expect in the business. It is not the same as turnover or the money in your bank account.

A simple example:

You enter 200 000 kroner as expected business profit, not 300 000. Skatteetaten then calculates the advance tax together with the other information in the tax deduction card.

Skatteetaten states that it is common to pay between 34 and 50 percent of the profit as advance tax. The agency recommends setting aside around 40 percent as a rule of thumb. This is not a fixed tax rate. Your tax may be lower or higher.

Create a separate tax account at the bank if that helps. For example, transfer a share every time a customer pays. Then the instalment amount will not be a surprise.

How to register the profit in the tax deduction card

Open the tax deduction card and enter expected profit under the topic “Business”. You can use Skatteetaten’s guide to calculate the amount.

Do this:

1. Make a realistic budget for the whole year.
2. Log in and open your tax deduction card.
3. Find the section for business and enter expected profit.
4. Also check salary, NAV payments, assets and debt.
5. See the new calculation and instalment amounts.

If you receive both salary and business income, you can change the distribution between advance tax and tax deduction from your salary. For example, you can choose higher deductions from salary and a lower invoice for advance tax. The calculated total tax will be the same.

Do not think that a private withdrawal from an ENK is salary. When you transfer money from the business to yourself, the withdrawal does not change the taxable profit.

Four deadlines for advance tax in 2026

The usual deadlines are 15 March, 15 June, 15 September and 15 December. Skatteetaten takes weekends and public holidays into account, so always check the date on the invoice.

The invoice usually arrives around three weeks before the deadline. It is in your online bank if you use eFaktura. Otherwise, it arrives in your Altinn inbox. If you have opted out of digital communication, you receive it by post.

Put the dates in your calendar yourself. A missing invoice does not mean the tax disappears. Check Claims and payments on My page at Skatteetaten if you are unsure.

VAT is a different payment with different deadlines. If the business exceeds the threshold, see the guide on VAT for sole proprietorships.

When should you change the advance tax?

Change the tax deduction card when expected profit or the rest of your financial situation changes. You can make changes as many times as you need up to 15 December.

Update when:

• you get more or fewer assignments than planned
• a major cost changes the profit
• you start or leave a regular job
• you receive sickness benefit or parental benefit from NAV
• the business goes from profit to loss

If you have uneven income, you can change the distribution between the quarters. Skatteetaten considers income uneven when expected profit in one quarter is two thirds or less of the amount that has been set. You can then pay less in a weak period and more in a strong period. The total amount does not change merely because the distribution changes.

If you have unpaid claims with Skatteetaten, the option for your own quarterly distribution may be hidden.

What do you do if the invoice has already arrived?

You can change the tax deduction card after the invoice has been sent, but you cannot simply pay an amount you choose yourself. Wait for Skatteetaten to process the change.

• If the change is approved, you pay the new instalment amount.
• If the advance tax is set to zero, the invoice can be deleted without payment.
• If the change is not approved before the deadline, you must pay the amount on the invoice.
• If you have paid too much, you can pay less in the next instalment or get money back in the tax assessment.

After 15 December, you must contact Skatteetaten to change the advance tax for the same year.

What happens if you pay late?

One late instalment may cause the advance tax for the rest of the year to become due. This is the most important trap in the scheme.

If Skatteetaten has not received the payment within seven calendar days after the deadline, the agency may send a notice of compulsory collection for the entire remaining amount for the year. The notice gives a 14-day payment deadline.

If you still do not pay, Skatteetaten may deduct money from income or take a lien on something you own. Late-payment interest is added.

First check whether the tax deduction card is correct if you cannot pay. Then get in touch early. Do not wait for the enforcement notice. The separate guide on outstanding tax and payment problems explains possible next steps, but advance tax has its own deadlines.

Too much, too little or a loss

Too little advance tax normally becomes outstanding tax the following year, while too much is refunded. You can correct the calculation along the way.

If you see after the year’s final instalment that you have paid too little, you can pay additional advance tax by 31 May the following year. Then you avoid interest on the amount that would otherwise become outstanding tax.

A completely new ENK that expects a loss in its first year should normally not enter the loss in the tax deduction card. State it in the tax return. If Skatteetaten has already calculated advance tax, set expected business profit to zero to have the invoices reduced or deleted.

You must still submit a tax return for an ENK. It is submitted together with your private tax return and includes a business specification. See the tax return explained and check the annual deadline.

A simple routine throughout the year

Update a small tax budget every month. Then you discover changes before the payment deadline.

Use this routine:

1. Record income and costs at least every month.
2. Calculate new expected annual profit.
3. Compare it with the amount in the tax deduction card.
4. Move money to the tax account.
5. Check the invoice three weeks before each instalment.
6. Change the tax deduction card immediately when the deviation becomes large.

On SamfunnPrep’s tools page, you can gather practical tasks and find more guides for everyday life in Norway. SamfunnPrep provides general guidance; ask Skatteetaten or an accountant about your specific calculation.