Yes, it is possible to cancel a single ticket out of a group of four on the same booking, but the process usually requires "splitting the PNR" (Passenger Name Record). In 2026, most airline websites and mobile apps do not allow you to cancel just one passenger from a multi-person itinerary online. To do this, you typically must call the airline's customer service or use their live chat feature. The agent will move the person who needs to cancel onto a new, separate reservation number, leaving the other three passengers on the original booking undisturbed. Once the individual is on their own PNR, their ticket can be canceled according to the fare rules (e.g., for a refund, credit, or with a fee). It is important to note that if you are on a "Basic Economy" or highly restrictive promo fare, you may not receive any refund or credit, but "splitting" the reservation still ensures that the "no-show" of one person doesn't accidentally trigger the cancellation of the remaining passengers' return flights.