Carpools save money. When one shares a car/vehicle with other commuters he or she saves on fuel cost, parking cost and vehicle maintenance cost.

Carpools decongest roads.

Carpools reduce pollution and carbon dioxide emissions thereby reducing global warming.

Carpools reduces driving related stress for participants who are not driving on a specific ride. The participants take turns sharing their vehicles and driving with others.

Higher occupancy rates also can reduce consumption of oil thereby reducing corresponding political and economic risks, emissions of greenhouse gases, common pollution.

Carpools save considerable expenses from gasoline, oil, tires, car depreciation, tolls, parking, and in some cases insurance.

Carpools may provide social connections in an increasingly disconnected society. New online carpooling services are offering new ways to make social connections through discussion sites and custom ridesharing services.

Some larger carpools offer "sweeper services" of late pick-up options for people having to stay longer at work. One form of backup is an arrangement with a local taxi company.

There are designated carpool lanes on highways (usually called High-Occupancy Vehicle, or HOV, lanes), which may make travel faster.