You must pay to the tax collector an amount corresponding to the employer's National Insurance contributions for all your employees for the two preceding months no later than on the fifteenth day of January, March, May, July, September and November, respectively (for example 15 March for the period January-February).
The payment record should preferably be reported via Altinn using the form ' Employer’s payment record for National Insurance contributions and payroll withholding tax'. Reporting takes place using the same form as for the tax withholdings. The same deadline therefore applies: by the fifteenth of the month after the end of the payment period.
If it is not possible for you to submit the form electronically via Altinn, you can submit it on paper. The Norwegian Tax Administration has its own customer ID (KID) number generator which generates KID numbers to be used on payment of employer's National Insurance contributions. You can also find the bank account number of each tax collector there. If you cannot use the KID number generator, you must contact the tax collection office in order to have a payment form sent to you.
It is important for the authorities to know whether you have forgotten the deadline or had no paid employees during the period. You are therefore required to submit a reporting form (on which 'zero' is entered in the amount fields) even if you have not paid tax or employer's National Insurance contributions.