A medical certificate does not expire on one date — its privileges step down. Every step runs through the last day of the calendar month, and the age test is your age on the day of the exam. The FAA does not care what class is printed on the card once a higher step has lapsed: a second-class medical simply becomes a third-class medical.

Example: a second-class exam on 15 Aug 2025 at age 40+ gives commercial privileges through 31 Aug 2026, then private privileges through 31 Aug 2027. Under 40 the private step would run through 31 Aug 2030. To fly for compensation again after 31 Aug 2026 you need a new second-class exam — the private step keeps running untouched in the meantime.

What needs what. Exercising commercial-pilot privileges (a jump pilot on the payroll, a ferry flight for pay, a Part 135 crew seat, a two-pilot Part 121 SIC) needs at least second-class privileges (61.23(a)(2)). Exercising ATP pilot-in-command privileges (any Part 121 captain, any PIC seat that requires an ATP) needs first-class (61.23(a)(1)). Everything a private pilot may do — including flight training you are paying for, and taking a checkride — needs only third-class privileges. A flight instructor giving instruction who is not acting as PIC or a required crewmember needs no medical at all (61.23(b)(7)); when the instructor is PIC (student not yet solo-endorsed, a rusty-pilot flight review) at least third-class or BasicMed applies. Gliders never need a medical; balloons don't either except commercial balloon flights for hire, which need second-class (61.23(a)(2)(iii), since Nov 2022). Sport pilots may substitute a valid U.S. driver's license for a medical (61.23(c)) — see below.

BasicMed (61.23(c)(3) · 61.113(i) · part 68) is an alternative to a third-class medical for private-pilot flying. Eligibility: you held any FAA medical at some point after 14 July 2006 (it may be expired); your most recent medical was not suspended or revoked, your most recent special-issuance authorization was not withdrawn, and your most recent medical application was not completed and denied; you hold a valid U.S. driver's license; a state-licensed physician completed the CMEC checklist within the preceding 48 calendar months (through the last day of the 48th month); you finished the online medical course within the preceding 24 calendar months; and if you have a condition that could affect flying you are under a physician's care. Keep the checklist and course certificate in your logbook (61.113(i)(3), 68.3). A one-time special issuance is required first for the cardiovascular, neurological and mental-health conditions listed in 68.9. Aircraft limits: up to 12,500 lb max takeoff weight and up to 7 occupants (you plus 6 passengers), not a transport-category rotorcraft, at or below 18,000 ft MSL, not over 250 knots indicated, inside the U.S. unless the host country allows it.

What BasicMed allows. Only private-pilot privileges — no commercial operations (jump pilot, Part 135, ferry for pay). The private-pilot exceptions in 61.113(b)–(h) still apply (business-incidental flying, pro-rata cost sharing, charity flights, aircraft sales demos), a CFI may be paid for instruction while acting as PIC under BasicMed (61.23(c)(1)(vii)), examiners may administer checkrides under it (61.23(c)(1)(viii), Nov 2024), you may take a practical test on it, and you may act as a 91.109 safety pilot (required-crewmember use allowed since Nov 2022). A jump pilot for hire still needs a real second-class medical.

Special issuance holders: the same ladder applies, but the medical expires no later than the Authorization's own validity date (67.401(a)) — the earlier date governs. A SODA (Statement of Demonstrated Ability, for a static condition) does not expire (67.401(b)) and the ordinary ladder applies. Either may be withdrawn by the Federal Air Surgeon (67.401(f)).

Sport pilots on a driver's license (61.23(c)(2)): comply with the license's restrictions and any court or DMV order; if you ever applied for an FAA medical, you were found eligible for at least third-class on the most recent application; your most recent medical was not suspended or revoked and no special issuance was withdrawn; and you don't know (or have reason to know) of any condition that would make you unable to fly safely. Night flying as a sport pilot requires BasicMed (61.23(c)(1)(vi)).

Sources: 14 CFR 61.23 (Amdt. 61-159, July 2025 — (a), (b)(7), (c), (d)); 61.113(i) (Amdt. 61-158, Nov 2024); Amdt. 61-152 (Nov 2022 — safety pilot, commercial balloons); part 68 (68.3, 68.9); 67.401; FAA AC 68-1A. This is a summary — the eCFR text controls.