When should you change to winter tires?
The date on the calendar matters less than the temperature of the road. The real questions are when summer tires stop gripping well enough and when the law where you drive starts to care.
The 7 °C rule of thumb
The rubber compound of summer tires hardens as it gets cold and loses grip. Winter tires use a softer compound and a tread with many fine slits, called sipes, that grip on snow and slush. Tire makers and motoring clubs commonly name about 7 °C as the point below which winter tires grip better. Watch the morning temperatures, not the afternoon ones: when they are regularly close to freezing, it is time.
What the law says
Rules differ from country to country, so check the current rules where you drive. Two examples: in Germany winter tires are required when roads are icy, snowy or slushy, and only tires with the Alpine symbol, a mountain with a snowflake, count as winter tires. The popular rule of thumb there is “O to O”, from October to Easter. In Austria cars must have winter tires from 1 November to 15 April whenever there are wintry conditions.
The legal minimum tread depth across the EU is 1.6 mm, but for winter tires experts recommend replacing them much earlier, at about 4 mm, because grip on snow drops quickly as the tread wears.
Check the tires before you fit them
- Tread depth: measure it at several points across the tire, not just in one groove.
- Age: the last four digits of the DOT code show the week and year of production, for example 4219 means week 42 of 2019. Older rubber hardens even when the tread looks fine.
- Damage: cracks, bulges on the sidewall and uneven wear.
- Matching: tires on one axle should be the same model with similar tread depth.
A short example
If the forecast shows nights around 0 °C from the third week of October and the first snow is expected in November, plan the change for mid-October. Waiting for the first snow usually means waiting in a queue at the tire shop while still driving on summer tires.
For tire shops
For a tire shop the same question decides when to start inviting clients. In OrgLines, automations and the AI assistant prepare reminders and task lists for your team before the season, based on your client base. There is no online booking; your team schedules requests as tasks.