Spencer Shay was 26 years old when the original iCarly series began in 2007 (during Season 1).

Canonical age in the show

  • In‑universe, Carly is stated to be 13 years old when the show starts, and Spencer is introduced as her 26‑year‑old brother and guardian.
  • This roughly 13‑year age gap remains consistent throughout the original run, so Spencer ages from about 26 to around 30–31 by the end of the 2012 series.

How fans extrapolate his age today

  • Since the original iCarly premiered in 2007 , and the reboots and later discussions place that premiere about 15 years before the 2022 revival , fans often model Spencer as being around 41 years old in the current timeline.

So the clean answer for the original show: Spencer was 26 years old in Season 1 of iCarly.