Underpaid tax - you owe money

If you ended up with underpaid tax or additional tax payment, then you paid too little tax last year and now owe money.

Payment deadlines

If you have to pay more than NOK 1,000 in underpaid tax, the amount will be split into two instalments. The deadline for payments depends on when you received your tax assessment notice:

  • If you received your assessment notice on 20 June, the deadline will be 20 August for the first instalment and 24 September for the second.
  • If you received your notice on or after 15 August, the deadline for the first instalment will be three weeks after the date on which your tax assessment was ready and eight weeks after your tax assessment was ready for the second instalment.

If your payment deadline falls on a Saturday or Sunday, you can pay on the Monday (the first working day) after the deadline.

You must pay the underpaid tax even if you have made changes after the deadline for submitting the tax return or an appeal. If you do not pay the outstanding tax on time, interest will accrue on the overdue amount until you pay the amount in full.

If you do not pay by the deadline for the first instalment, you'll be considered to have made no payment at all. If you need help, contact the tax collector in your municipality.

If you have underpaid tax of less than NOK 1,000, the deadline for payment will depend on when your received your tax assessment notice.

  • If you received your tax assessment notice on 20 June, the deadline for payment will be 20 August.
  • If you received your assessment notice on or after 15 August, the deadline for payment will be three weeks after the date on which your tax assessment was ready.

If your payment deadline falls on a Saturday or Sunday, you can pay on the Monday (the first working day) after the deadline.

You must pay the underpaid tax even if you have made changes after the deadline for submitting the tax return or an appeal. If you do not pay the outstanding tax on time, interest will accrue on the overdue amount until you pay the amount in full.

You do not have to pay underpaid tax of less than NOK 100

How to pay

Well in advance of the due date, you'll receive an invoice with payment information. If you have an e-ID, you'll receive your invoice and payment information in Altinn. If not, you'll receive your invoice and payment information in the post.

E-invoice

You can set up an e-invoice agreement with us for tax payments.

Account number and KID

Use the account number and the KID stated on the invoice. If you have not received an invoice and payment information, you'll find the information you need here: 

Interest

The annual interest rate is 0.59 percent, determined from 1 July in the income year through to the due date for the first instalment of underpaid tax in the following tax year. 

This is an example of how much the interest on underpaid tax could be:

Calculated tax - 2018 income year: NOK 100,000
Withholding tax: NOK 80,000
Underpayment: NOK 20,000

Interest surcharge 0.59% from 1 July 2018 to 20 August 2019 (416 days) = NOK 134
Amount payable: NOK 20,134

Avoid interest on underpaid tax

If you know you'll have to pay underpaid tax, you can opt to pay more by 31 May in order to avoid having to pay interest on the underpaid tax. 

The deadline for paying underpaid tax will not change if your tax return deadline is deferred, if you applied for deferral.

Payment after the deadline will not be taken into account in the final tax settlement.

If your payment deadline falls on a Saturday or Sunday, you can pay on the Monday (the first working day) after the deadline.

Use the account number and KID number that you'll find in your tax return.

  • If you did not make any changes to your tax return, you will find the amount you owe on the last page.
  • If you made changes to your tax return that could affect the outcome, you can use the tax calculation program to calculate the amount.

If you have paid too much underpaid tax, you will be credited with interest on the refund.

Additional advance tax

If you realise that you'll have underpaid tax, you may wish to consider paying additional advance tax by 31 May. If you do, you will not have  to pay interest on the underpaid tax.

When you have received your tax return, you can use the payment information given in the tax return in order to pay. If you wish to pay before you have received your tax return, you can generate a KID number and make the payment to your tax collector.

Avoid underpaying your tax

If your underpaid tax remains unpaid by the due date, penalty interest will accrue and the tax collectors will implement measures to collect the tax.

Penalty interest will accrue from the due date until the outstanding amount is paid in full. The Ministry of Finance adjusts the interest rate twice a year.

Possible measures when you fail to make a payment:

  • distraint proceedings
  • expense deductions
  • compulsory sale
  • bankruptcy petition
  • offsetting

You must expect penalty fees and/or having the payment default added to your credit record if any of the above actions are taken.

If you do not pay your underpaid tax within three years, your pension credits may be reduced.

Read more about measures to collect unpaid underpaid tax.