Upvote:4
For Indian citizens travelling to Mexico, Timatic, the system used by airlines to check required documentation states:
βThe following are exempt from holding a visa:
Passengers with a permanent residence permit issued by United Kingdom for a maximum stay of 180 days.β
Source: https://www.timaticweb2.com/integration/external.php?ref=d975cfc59f5c0abd06d16e872198110b
This means that your husband must have Indefinite Leave to Remain in order to qualify for visa-free entry. If he has Limited Leave to Remain, he needs a visa.