1999–2000 National League 1

1999–2000 National League 1
Countries England
ChampionsOtley (2nd title)
Runners-upBirmingham & Solihull (also promoted)
RelegatedReading, Blackheath
Matches played182

The 1999–2000 National League 1, sponsored by Jewson, was the thirteenth full season of rugby union within the third tier of the English league system.