1988–89 Courage League National Division Three
The 1988–89 Courage League National Division Three was the second full season of rugby union within the third tier of the English league system, currently known as National League 1. Each team played one match against the other teams, playing a total of eleven matches each. Plymouth Albion won all their eleven matches and won promotion to National Division Two. Rugby finished second, winning ten of their eleven matches, and were also promoted. Metropolitan Police and Maidstone finished in the bottom two places and both clubs were relegated to Area League South for the following season. Metropolitan Police was relegated on points difference and Maidstone lost all of their matches.
Participating teams and locations
| Team | Ground | Capacity | City/Area | Previous season |
| Askeans | Broad Walk | Kidbrooke, London | Promoted from Area League South | |
| Exeter | County Ground | 5,200 | Exeter, Devon | 9th |
| Fylde | Woodlands | 9,000 | Lytham St Annes, Lancashire | 6th |
| Maidstone | William Davey Memorial | Maidstone, Kent | 8th | |
| Metropolitan Police | Imber Court | East Molesey, Surrey | 7th | |
| Nuneaton | Harry Cleaver Ground | Nuneaton, Warwickshire | 10th | |
| Plymouth Albion | Beacon Park | 3,500 | Plymouth, Devon | 3rd |
| Rugby | Webb Ellis Road | 1,000 | Rugby, Warwickshire | Promoted from Area League North |
| Sheffield | Abbeydale Park | 3,200 | Dore, Sheffield, South Yorkshire | 4th |
| Vale of Lune | Powderhouse Lane | Lancaster, Lancashire | 5th | |
| Wakefield | College Grove | 3,000 | Wakefield, West Yorkshire | 1st |
| West Hartlepool | Brierton Lane | Hartlepool, Cleveland | 2nd |