I'm quite baby-faced
and regularly got IDed for many years. So for me, it was when, with the coming of some grey hairs and a bit of proper stubble (rather than bumfluff), I actually went more than a few months without having to produce ID to buy a pint. I was about 28 at the time.
(SnowyTheWereRabbit the Leporid from Hell, Thu 7 Jun 2012, 19:10, 2 replies)

The IDing stopped soon after I began keeping my hair short.
As if by coincidence, round about the same time I started being able to get jobs that were more challenging and better paid than sweeping floors and unblocking drains eight hours a day.
( The Mock TurtIe ™ --- Thinks you are a cunt, on, Thu 7 Jun 2012, 21:59, closed)

I once got ID'd for cigarettes
back when the legal age was 16. I was 28. And in the shop where I'd once worked myself as a 16-year-old shelf-stacker. I politely protested, and the pimply youth at the till called his manager out for support. The (long) queue behind me tutted and sighed as we waited for the manager to fight her way to the front of the shop. She looked at me for a moment, then said, "for christ's sake Steve, give the man his cigarettes."
( Zoroastermouse thinks therefore he am, Fri 8 Jun 2012, 0:20, closed)