Drivers in America using Boston car hire services must follow Massachusetts driving laws. You must drive on the right-hand side of the road, always wear a seat belt, and never use a mobile phone while driving unless you have a hands-free device. The maximum BAC limit is 0.08% or 0.02% if you are under 21. Always keep your driving licence, IDP, car hire registration papers, car hire agreement paperwork, and any insurance documents with you. The speed limits in Boston have a default limit of 30 mph for residential areas, 20 mph for school areas, 55 mph on undivided, divided roads and urban freeways, and 65 mph on rural freeways.