| Member City | Year Joined |
| 1. Beavercreek | (1988) |
| 2. Bellbrook | (2004) |
| 3. Blue Ash | (1992) |
| 4. Centerville | (2004) |
| 5. Englewood | (2004) |
| 6. Indian Hill | (1993) |
| 7. Kettering | (1988) |
| 8. Madeira | (1994) |
| 9. Mason | (1997) |
| 10. Miamisburg | (1988) |
| 11. Montgomery | (1990) |
| 12. Piqua | (2002) |
| 13. Sidney | (1993) |
| 14. Springdale | (1991) |
| 15. Tipp City | (1996) |
| 16. Troy | (1989) |
| 17. Vandalia | (1988) |
| 18. West Carrollton | (1988) |
| 19. Wilmington | (1988) |
| 20. Wyoming | (1992) |
| 21. Fairfield | (2019) |