Winter tyres must be used on Finnish roads from Monday 1 November, but with a significant caveat: if so required by weather or road surface conditions.
Changes to Finland's Road Traffic Act, which came into effect last year, placed more responsibility on drivers to determine if winter tyres must be used between 1 November and 31 March, based on the prevailing conditions.
Winter tyres can be either studded or non-studded.
According to a press release by the Finnish Transport and Communications Agency Traficom, non-studded tyres — also know as friction tyres — are a better option for snow-covered roads.
"On icy roads, studded tyres have better grip, but they cause more road wear than friction tyres do. In addition, studs detach fine particles, which have harmful effects on human health, from road surfaces," the statement said.
The agency added that the main tread on all car and van tyres must be at least three millimetres thick, rising to five millimetres for particularly difficult driving conditions, such as slushy or snowy roads.