According to the official rules of the Bay Area Rapid Transit (BART) in 2026, eating and drinking are strictly prohibited inside the "paid" areas of the stations and on all train cars. This policy is in place to maintain the cleanliness of the new "Fleet of the Future" trains and to prevent spills that can damage electrical components or create slipping hazards for other passengers. While you can legally carry a closed container of coffee in your bag or hand, you are technically not allowed to consume it once you have passed through the fare gates. Enforcement of this rule can vary; while BART police may prioritize safety over a morning latte, you can still be issued a citation and a fine if caught drinking. However, in the reality of the daily commute, many riders carry spill-proof, vacuum-sealed travel mugs that they keep closed while on the train. For the best experience and to avoid any legal trouble or "side-eye" from fellow commuters, it is best to finish your coffee at the street level before entering the station or wait until you have exited your destination station to take your first sip.