The 2009-10 National League 1, previously known as National Division 2, is the first season of the third division of the English rugby union competitions since the professionalised format of the second division was introduced with widespread league changes made by the RFU.

[1] As the new second division would reduce teams from 16 to 12, there were plenty of new additions to National League 1, itself increasing from 14 to 16 teams, with Esher, Newbury, Manchester, Manchester and Sedgley Park all dropping down from the old National 1 while Nuneaton and London Scottish came up from the 2008–09 National Division Three North and 2008–09 National Division Three South respectively (these divisions themselves now renamed National League 2 North/South).

[2][3][4][5] At the end of the season Esher finished as champions, way ahead of runners up and newly promoted London Scottish, suffering only one defeat and going straight back up to the 2010–11 RFU Championship.

[7] The other two sides to join them would be Nuneaton who went straight back down after one season and Newbury Blues who also suffered a second relegation in a row, losing out to 13th place Otley by just 2 points.

124 - 5 Wharfedale at home to Manchester on 26 September 2009 148 - 0 Esher away to Manchester on 5 September 2009 148 - 0 Esher away to Manchester on 5 September 2009 Blaydon away to Manchester on 19 September 2009 Esher away to Manchester on 5 September 2009 N/A - multiple teams Newbury Blues away to Blackheath on 12 September 2009 [20][21][22][23] Sam Ulph for Esher away to Manchester on 5 September 2009 Johannes Schmidt for Cambridge at home to Manchester on 10 April 2010 Seb Jewell for Esher at home to Manchester on 24 April 2010 Sam Ulph for Esher away to Manchester on 5 September 2009 N/A - multiple players Mitch Burton for Newbury Blues away to Blackheath on 12 September 2009 [24][25][26][27][28] London Scottish at home to Esher on 16 January 2010 Blaydon at home to Nuneaton on 17 April 2010 London Scottish Manchester [29]