Counties 2 Herts/Middlesex (formerly London 3 North West) is a level 8 league within the RFU league structure and is made up of teams predominantly from north-west London and Hertfordshire. Promoted sides move up to Counties 1 Herts/Middlesex while relegated teams drop to Counties 3 Herts/Middlesex. Following the RFU's Adult Competition Review, from season 2022-23 it adopted its current name Counties 2 Herts/Middlesex.

Teams for 2024-25

Departing were Brunel University and Ealing Trailfinders 1871, both promoted to Counties 1 Herts/Middlesex. Hendon were relegated to Counties 3 Herts/Middlesex. Joining were Enfield Ignatians and Hampstead, both relegated from Counties 1 Herts/Middlesex together with Verulamians and UCS Old Boys, both promoted from Counties 3 Herts/Middlesex. With three teams departing and four joining, the league ran with eleven sides.

Teams for 2023-24

Departing were Cheshunt and London Scottish Lions, both promoted to Counties 1 Herts/Middlesex. Royston were relegated to Counties 3 Herts/Middlesex. Joining were Brunel University and Old Millhillians, both promoted from Counties 3 Herts/Middlesex. With three teams departing and two joining, the league ran with ten sides.

Teams for 2022-23

This was the first season following the RFU Adult Competition Review with the league adopting its new name of Counties 2 Herts/Middlesex. Returning were six of the ten teams from the previous season supplemented by the top five from Herts/Middlesex 1. Departing were the top three sides Finchley, Welwyn and Hitchin, all promoted to Counties 1 Herts/Middlesex. Finsbury Park, 8th in 2021-22, did not return for the new season instead dropping to Middlesex RFU Merit 2.

Teams for 2021–22

The teams competing in 2021-22 achieved their places in the league based on performances in 2019-20, the 'previous season' column in the table below refers to that season not 2020-21. Stevenage Town, 3rd in 2019-20, did not return for the new season instead dropping to Middlesex RFU Merit 3. This meant the league started with eleven clubs competing. Old Merchant Taylors', who finished 9th in 2019-20, withdrew from the league in November 2021, consequently it was completed with ten teams.

Season 2020–21

On 30 October the RFU announced that a decision had been taken to cancel Adult Competitive Leagues (National League 1 and below) for the 2020/21 season meaning London 3 North West was not contested.

Participating Clubs 2019–20

Participating Clubs 2018–19

Participating Clubs 2017–18

Participating Cubs 2016-17

Final league table

Participating Clubs 2015-16

Participating Clubs 2014-15

Participating Clubs 2013-14

Participating Clubs 2012-13

Participating Clubs 2009-10

Original teams

When this division was introduced in 2000 (as London 4 North West) it contained the following teams:

London 3 North West honours

London 4 North West (2000–2009)

Originally known as London 4 North West, this division was a tier 8 league with promotion up to London 3 North West and relegation down to Herts/Middlesex 1.

London 3 North West (2009–present)

League restructuring by the RFU ahead of the 2009–10 season saw London 4 North East renamed as London 3 North West. Remaining as a tier 8 league promotion was to London 2 North West (formerly London 3 North West), while relegation continued to Herts/Middlesex 1.

Number of league titles