This guide is for general information only and is not legal advice. Laws change — verify current rules with your state DOT or a licensed attorney before relying on this for any legal matter. Read full disclaimer.
State law allows only one earpiece at a time while cycling — covering both ears is prohibited in California. See Cal. Veh. Code § 27400 (Headsets and earplugs).
Use a single earbud and keep the other ear open to traffic. Bone-conduction headphones are a popular workaround because they leave both ear canals uncovered.