Announced today- Regulated rail fares in England are to be frozen in price until March 2027- that is no rise in 2026
Regulated fares are full price fares, and do not include reduced fares such as Advance tickets (or Flex 70 on LNER) or rail rover/ranger tickets- those are up to the train companies to set prices.
This does not include Wales and Scotland (except cross border fares) as those are determined by the devolved governments.
Nor does it seem to include metro systems, such as TfL (the London Underground etc) where any rise is yet to be determined.
https://www.bbc.co.uk/news/articles/cwygx71g3n7o
Also the £3 maximum bus fare in England also remains in place until March 2027