| 191 runs | v Derbyshire | The Cooper Associates County Ground, Taunton | 2022 | tt11106 |
| 143 runs | v Essex | The Ford County Ground, Chelmsford | 2011 | tt2242 |
| 117 runs | v Gloucestershire | County Ground, Taunton | 2006 | tt368 |
| 114 runs | v Essex | The Cloudfm County Ground, Chelmsford | 2019 | tt8035 |
| 108 runs | v Glamorgan | The Cooper Associates County Ground, Taunton | 2024 | tt13813 |
| 98 runs | v Hampshire | The Ageas Bowl, Southampton | 2017 | tt6437 |
| 95 runs | v Gloucestershire | County Ground, Taunton | 2005 | tt231 |
| 89 runs | v Glamorgan | County Ground, Taunton | 2005 | tt194 |
| 84 runs | v Kent | The Kent County Cricket Ground, Beckenham | 2010 | tt1781 |
| 80 runs | v Gloucestershire | Seat Unique Stadium, Bristol | 2023 | tt12322 |
| 79 runs | v Middlesex | County Ground, Taunton | 2010 | tt1829 |
| 74 runs | v Glamorgan | Sophia Gardens, Cardiff | 2021 | tt9825 |
| 67 runs | v Worcestershire | County Ground, Taunton | 2008 | tt966 |
| 66 runs | v Glamorgan | Sophia Gardens, Cardiff | 2020 | tt8995 |
| 66 runs | v Sri Lanka Cricket Development XI | The Cooper Associates County Ground, Taunton | 2022 | tt10843 |
| 64 runs | v Glamorgan | County Ground, Taunton | 2013 | tt3726 |
| 63 runs | v Warwickshire | County Ground, Taunton | 2012 | tt2963 |
| 63 runs | v Hampshire | The Ageas Bowl, Southampton | 2019 | tt8043 |
| 63 runs | v Hampshire | The Cooper Associates County Ground, Taunton | 2024 | tt13756 |
| 55 runs | v Kent | The Cooper Associates County Ground, Taunton | 2019 | tt8048 |