They can. But I don't really see how that could happen if you didn't also have a mortgage. You would easily be able to finance this, unless your property was a

They can. But I don't really see how that could happen if you didn't also have a mortgage. You would easily be able to finance this, unless your property was also pretty much worthless. And if it was practically worthless you'd either not pay any property tax at all, due to deductibles, or pay basically nothing. In Norway property tax (where applicable, it's up to local government) is measured as a percentage of the taxable value of primary residence. Usually 0,2 per mille or around that. The taxable value is less than the property value. It's a progressive scheme, everything below 10MNOK is measured as 25% of property value (marked value-ish), and 75% for everything over 10MNOK. For secondary houses the taxable value is set to the property value.