One-party vs two-party consent
Whether one person (one-party) or everyone (all-party / 'two-party') on a call must agree before it can be recorded, it depends on the US state.
Call-recording laws turn on who must consent. In one-party-consent states, a single participant's agreement (which can be yours) is enough to record. In all-party (commonly called two-party) consent states like California under CIPA, everyone on the call must consent. For calls across state lines, the safe practice is to follow the strictest applicable state and disclose recording to all parties.
Educational, not legal advice, verify current rules with your own counsel.
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