London & South East Premier (up until 2016-17 known as National League 3 London & South East) is a level five league in the English rugby union system.^[7] It is one of four leagues at this level, with its counterparts; South West Premier, Midlands Premier and North Premier. The format of the league was changed at the beginning of the 2009–10 season following re-organisation by the Rugby Football Union while the name change from National League 3 to Premier was introduced for the 2017-18 season to make it more obvious that it is a regional league.^[7] London & South East Premier is the highest regional rugby union league covering London and south east England.

The club that finishes in first place is automatically promoted to National League 2 South. The runner-up meets the second placed team of South West Premier with the winner also gaining promotion. Relegated teams drop down to either London 1 North or London 1 South depending on location, and other factors such as the location of relegated and promoted teams in other divisions.

Nine of the fourteen teams participated in last season's competition. They are joined by Guernsey and London Irish Wild Geese who were relegated from National League 2 South, along with three promoted sides; Brighton, Rochford Hundred and Sevenoaks.^{[8][9][10][11] [12]} Teams leaving the division included Sutton & Epsom who were promoted into National League 2 South as champions and Westcliff who won the promotion playoff, while teams relegated from the league included Brentwood, Chingford and Shelford (all London 1 North).

Nine of the fourteen teams participated in last season's competition. They are joined by Wimbledon who were relegated from National League 2 South, along with four promoted sides; Bedford Athletic, Brentwood, Chingford and CS Rugby 1863. Bedford Athletic had initially been promoted into Midlands Premier but were level transferred into London & South East Premier as the nearest club geographically to address an imbalance of teams in the league. Teams leaving the division included Barnes who were promoted into National League 2 South as champions along with Guernsey who won the promotion playoff, while teams relegated from the league included Southend Saxons (London 1 North), Towcestrians (Midlands 1 East) and Westcombe Park (London 1 South).

Nine of the fourteen teams participated in last season's competition. They are joined by Barnes who were relegated from National League 2 South along with three promoted teams Sidcup, Tring and Tunbridge Wells.^{[13][14][15][16]} Tonbridge Juddians were promoted into National League 2 South as champions along with Wimbledon who won the promotion playoff.^[17][18] Teams relegated from the league included Amersham & Chiltern and Colchester (London 1 North) and Chichester (London 1 South).^[19] To address an imbalance of teams, Towcestrians were level transferred into the league from the Midlands Premier, as they were the nearest team geographically.^[20]

Each season, the runners-up in the London & South East Premier, and South West Premier participate in a play-off for promotion to National League 2 South. The team with the best playing record, in this case Guernsey RFC, hosted the match and beat their opponents Bournemouth 38 – 23 to win promotion.

Nine of the fourteen teams participated in last season's competition. They are joined by Dorking and Southend Saxons who were relegated from National 2 South while three promoted teams, Amersham & Chiltern, Guildford and Sutton & Epsom were promoted into the league. London Irish Wild Geese were promoted to National League 2 South as champions while Eton Manor and Gravesend were relegated to London 1 North and London 1 South respectively. Originally, Westcliff were supposed to go down as the 14th placed team, but they were granted a reprieve when East Grinstead (who had finished 3rd) decided to take voluntary relegation, due to the loss of a key sponsor and dropped five leagues to Sussex Spitfire 1.^[21][22][23] Finally Bracknell were level transferred back to National League 3 South West after just one season to address an imbalance in teams after having finished 11th.^[24]

Current results see:- National League 3 London & South East results ^[97]

Each season, the runners-up in the National League 3 London and SE, and National League 3 South West participate in a play-off for promotion to National League 2 South. The team with the best playing record, in this case Wimbledon RFC, hosted the match and beat their opponents Dings Crusaders RFC 55 – 5 to win promotion.

Notes;

The runners-up in the National League 3 London and SE, and National League 3 South West participate in a play-off for promotion to National League 2 South. The team with the best playing record, in this case Tonbridge Juddian, host the match and their opponents are Barnstaple. Juddians lost the match 31 – 30 to a penalty in the last minute of the match and will stay in National 3 London and SE for next season.^[25]

The runners-up in the National League 3 London and SE, and National League 3 South West participate in a play-off for promotion to National League 2 South. The team with the best playing record, in this case Exmouth, hosts the match; their opponents were Barnes and the match was played on 25 April 2015. At the end of full-time the match score was 22 – 22, and Barnes scored the only points in extra-time, to win the match 27– 22.^[26]

After extra time (80 mins: 22 – 22)

First season as a national league

In the first season of the English rugby union league pyramid, sponsored by Courage, there was four, tier five leagues. These were London Division 1, Midland Division 1, North Division 1 and South West Division 1. In 1987 the geographical area for teams in the south-east of England was known as the London and South East Division and covered the counties of Essex, Hampshire, Kent, Middlesex, Norfolk, Suffolk, Surrey and Sussex. The league was also known as London League 1 and London 1. There were eleven teams in the league and they played each team once, giving each team ten matches.^[30] This system prevailed for five seasons, and in 1992–93 the number of teams increased from eleven to thirteen. The following season (1993–94) the league was reorganised and the four tier five leagues became two; National 5 North and National 5 South.^[31] After three seasons, in 1996–97, a further reorganisation occurred, and there was a return to four, tier five leagues; with London Division One covering the same area as before.^[32] This system prevailed until 2009–10 when the number of teams was increased from twelve to fourteen and renamed National League Three London & South East. The league name changed once more for the 2017-18, when it was renamed to London & South East Premier.^[7]

The top six teams from London Division One and the top six from South West Division One were combined to create National 5 South. London Division 1 was now the name of a tier six league and was one of two feeder leagues for National 5 South.

National 5 South was split and renamed London Division One and South West Division One, and the top four divisions increased in size. Lydney was promoted to National Division Three and all of the other teams, bar Camborne, were transferred to the tier four, National 4 South.^[37]

The division was renamed National League 3 London & SE following a restructuring of the national leagues which led to changes at all levels.

The division was renamed London & South East Premier in order to make it more obvious that it was a regional league and the pinnacle of the London & South East region.

Since season 2000–01 there has been a play-off between the runners-up of London & South East Premier and South West Premier for the third and final promotion place to National League 2 South. The team with the superior league record has home advantage in the tie. At the end of the 2018–19 season the London and south-east teams have been the most successful with thirteen wins to the south-west teams six; and the home team has won promotion on fifteen occasions compared to the away teams four.