All-season tires are tires which are designed to be left on a vehicle year-round. They are most suitable in temperate climates where the weather remains fairly stable, without any extremes. In areas where heavy snow and ice are common in the winter, it may not always be safe to use all-season tires, requiring car owners to install snow tires or winter tires during the winter months. For the most part, cars are sold with all-season tires installed, and when people buy new tires, it is usually assumed that they want all season models.
The advantage to using all-season tires is that they do not have to be changed to prepare for the winter, which cuts down on maintenance costs for the car. These tires also come in a range of styles, including sport and performance tires for sports cars, along with more generic low cost tires for basic sedans and wagons. All-season tires designed for trucks are also available.
The primary drawback to all-season tires is that they may not perform as well during winter. Specialized traction which helps cars navigate wet, muddy, icy, or snowy roads can hinder vehicle performance during other months, making it impractical on all-season tires. As a result, cars can be more prone to slipping and spinning out of control on winter roads with all-season tires, especially if drivers are going out shortly after a major storm, or driving before road crews have had a chance to clear the roads.
One compromise used by drivers in snowy areas is snow chains. Snow chains can be fitted over all-season tires to allow people to drive on snow. Fitting chains is easier and more convenient than changing tires for the winter, and people may be required to use chains or snow tires in certain areas during the winter due to safety concerns.
Performance ratings for all-season tires vary. Many manufacturers have basic guidelines which recommend when the tires should be changed and rotated; as a general rule, the more expensive the tires, the longer they last, although some performance tires can be quite costly and surprisingly short lived. However, drivers shouldn't go by manufacturer's recommendation alone. They should regularly inspect their tires for wear, pay attention to the sensor systems in the vehicle which provide feedback about tire performance, and replace tires which are worn or damaged. Driving on tires with very little tread left can be extremely hazardous, and cars with tires near the end of their lifespan may not pass safety inspections.