The 2018–19 Spartan South Midlands Football League season was the 22nd in the history of Spartan South Midlands Football League, a football competition in England.
The provisional club allocations for steps 5 and 6 were announced by the FA on 25 May.[1] The constitution is subject to ratification by the league at its AGM on 23 June.
| Competition: | Spartan South Midlands Football League Premier Division |
| Season: | 2018–19 |
| Winners: | Biggleswade |
| Promoted: | Biggleswade |
| Relegated: | London Tigers Stotfold |
| Matches: | 380 |
| Total Goals: | 1251 |
| Prevseason: | 2017–18 |
| Nextseason: | 2019–20 |
The Premier Division featured 16 clubs which competed in the division last season, along with four new clubs:
| Competition: | Spartan South Midlands Football League Division One |
| Season: | 2018–19 |
| Winners: | Harefield United |
| Promoted: | Broadfields United Harefield United |
| Relegated: | Codicote Hatfield Town |
| Matches: | 380 |
| Total Goals: | 1581 |
| Prevseason: | 2017–18 |
| Nextseason: | 2019–20 |
Division One featured 20 clubs in the division for this season, of which there are three new clubs:
| Competition: | Spartan South Midlands Football League Division Two |
| Season: | 2018–19 |
| Winners: | Bovingdon |
| Matches: | 182 |
| Total Goals: | 777 |
| Prevseason: | 2017–18 |
| Nextseason: | 2019–20 |
Division Two featured 13 clubs which competed in the division last season, along with two clubs joined from the Herts County League:
Also, Loughton Manor relocated and were renamed New Bradwell St Peter.