With London Scottish having been promoted, along with Old Haberdashers' and Hemel Hempstead being relegated, there were at least three places available in the division ; joining the league are Harpenden (relegated from 1 South East), Brunel University (promoted from Counties 1 Herts/Middx), Oxford Harlequins II and Windsor (both promoted from Counties 1 Tribute Southern North) - the extra space created by H.A.C receiving a level transfer to Regional 2 Anglia.

See below for a list of the teams set to compete in Regional 2 Thames in 2025/26, along with their 2024/25 positions :

Aylesbury - 10th in Regional 2 Thames, Round 2 of the Regional 2 South Plate of the Papa John's Community Cup

Beaconsfield - 4th in Regional 2 Thames, Quarter Finalists in the Regional 2 South Plate

Belsize Park - 3rd in Regional 2 Thames, Quarter Finalists in the Regional 2 South Plate

Brunel University - 1st in Counties 1 Herts/Middx, Winners of the Counties 1 Championship

Grasshoppers - 7th in Regional 2 Thames, Round 1 of the Regional 2 South Plate

Harpenden - 11th in Regional 1 South East, Round 2 of the Regional 1 Shield

London Irish Wild Geese - 5th in Regional 2 Thames, Round 2 of the Regional 2 South Plate

Marlow - 9th in Regional 2 Thames, Round 2 of the Regional 2 South Plate

OPRFC - 6th in Regional 2 Thames

Oxford Harlequins II - 1st in Counties 1 Tribute Southern North

Teddington - 8th in Regional 2 Thames, Round 1 of the Regional 2 South Shield

Windsor - 2nd in Counties 1 Tribute Southern North, Round 1 of Counties 1 Championship

Fixtures for the season will be released in due course.