When arriving to Finland from abroad, you will walk through the customs line to the arrival hall. If you have goods to declare, please select the red line. 

It is allowed to bring items such as tobacco products and alcohol from EU countries without customs declaration for personal use. From non EU countries it is allowed to bring items worth of 430 euros, and items exceeding that amount should be declared. Please check from Customs website how much it is allowed to bring different products to Finland.