Czy muszę wykazać dom w zeznaniu podatkowym (belastingaangifte)?

Yes, as a homeowner you declare your main residence in your annual income tax return (belastingaangifte): the eigenwoningforfait as income and your mortgage interest as a deduction, both in box 1. Many homeowners receive a refund as a result. You file online with your DigiD, and your first year as a migrant often uses the M-form (M-formulier).