You may become a Norwegian tax resident after spending 184 days in Norway during any rolling 12-month period. If the threshold is reached within your first calendar year of presence, residency generally starts from your first day in Norway that year. If your qualifying days span two calendar years, residency generally starts on 1 January of the year in which the threshold is reached. This rule only tracks the initial day-count test and does not calculate the effective start date of tax residency. Once tax residency is established, it does not automatically end when days leave the rolling window; separate departure requirements apply.
https://www.skatteetaten.no/en/person/taxes/get-the-taxes-right/abroad/tax-residence-in-norway-when-moving-to-or-from-norway/