List A Batting and Fielding Against Each Opponent by Greig Williamson
| Opponent | Matches | Inns | Not Out | Runs | HS | Ave | 100 | 50 | Ct | St |
| Bermuda | 1 | 0 | | | | | | | 0 | |
| Cumberland | 1 | 1 | 0 | 77 | 77 | 77.00 | 0 | 1 | 0 | |
| Denmark | 1 | 1 | 1 | 5 | 5* | | 0 | 0 | 0 | |
| Derbyshire | 4 | 4 | 0 | 32 | 20 | 8.00 | 0 | 0 | 0 | |
| Dorset | 1 | 0 | | | | | | | 1 | |
| Durham | 4 | 4 | 0 | 44 | 24 | 11.00 | 0 | 0 | 1 | |
| Gloucestershire | 1 | 1 | 0 | 7 | 7 | 7.00 | 0 | 0 | 0 | |
| Hampshire | 2 | 2 | 0 | 39 | 37 | 19.50 | 0 | 0 | 0 | |
| Ireland | 1 | 1 | 0 | 27 | 27 | 27.00 | 0 | 0 | 0 | |
| Kent | 1 | 1 | 0 | 0 | 0 | 0.00 | 0 | 0 | 0 | |
| Kenya | 2 | 2 | 0 | 15 | 15 | 7.50 | 0 | 0 | 0 | |
| Lancashire | 2 | 2 | 0 | 62 | 60 | 31.00 | 0 | 1 | 1 | |
| Lancashire Cricket Board | 1 | 1 | 0 | 28 | 28 | 28.00 | 0 | 0 | 0 | |
| Leicestershire | 2 | 2 | 0 | 12 | 10 | 6.00 | 0 | 0 | 0 | |
| Middlesex | 3 | 2 | 1 | 7 | 7 | 7.00 | 0 | 0 | 0 | |
| Middlesex Cricket Board | 1 | 1 | 0 | 16 | 16 | 16.00 | 0 | 0 | 1 | |
| Namibia | 2 | 2 | 1 | 9 | 8* | 9.00 | 0 | 0 | 0 | |
| Netherlands | 3 | 3 | 1 | 80 | 48 | 40.00 | 0 | 0 | 1 | |
| New Zealand | 2 | 2 | 0 | 35 | 25 | 17.50 | 0 | 0 | 0 | |
| Northamptonshire | 3 | 3 | 1 | 101 | 51* | 50.50 | 0 | 1 | 0 | |
| Nottinghamshire | 3 | 3 | 0 | 12 | 8 | 4.00 | 0 | 0 | 0 | |
| Somerset | 5 | 5 | 0 | 9 | 6 | 1.80 | 0 | 0 | 1 | |
| Surrey | 1 | 1 | 0 | 22 | 22 | 22.00 | 0 | 0 | 1 | |
| Sussex | 4 | 3 | 0 | 39 | 27 | 13.00 | 0 | 0 | 2 | |
| United Arab Emirates | 1 | 1 | 0 | 8 | 8 | 8.00 | 0 | 0 | 1 | |
| West Indies | 1 | 1 | 0 | 1 | 1 | 1.00 | 0 | 0 | 0 | |
| Wiltshire | 1 | 1 | 0 | 14 | 14 | 14.00 | 0 | 0 | 0 | |
| Worcestershire | 5 | 5 | 0 | 21 | 12 | 4.20 | 0 | 0 | 0 | |
| Yorkshire | 4 | 3 | 0 | 26 | 19 | 8.66 | 0 | 0 | 0 | |