The 18 teams were divided into three groups of six and each group played a double round-robin tournament. The top two teams from each group and the top two third-placed teams qualified for the knockout stage: a three-round single-elimination tournament. The top team from each group and the best second-placed team then played in a different quarter-final at their home ground. A free draw determined the placement of the remaining four teams and the semi-final and final match-ups.
†Durham were deducted 0.25 points for a breach of team salary payments in 2012.
| Pos | Team | Pld | W | L | T | NR | Pts | NRR |
| 1 | Northamptonshire Steelbacks | 10 | 7 | 3 | 0 | 0 | 14 | 0.329 |
| 2 | Somerset | 10 | 6 | 4 | 0 | 0 | 12 | 0.841 |
| 3 | Glamorgan | 10 | 5 | 5 | 0 | 0 | 10 | −0.168 |
| 4 | Warwickshire Bears | 10 | 5 | 5 | 0 | 0 | 10 | −0.410 |
| 5 | Worcestershire Royals | 10 | 4 | 6 | 0 | 0 | 8 | −0.327 |
| 6 | Gloucestershire Gladiators | 10 | 3 | 7 | 0 | 0 | 6 | −0.245 |
Somerset won the toss and elected to bat. Northamptonshire Steelbacks won the toss and elected to bat. Lancashire Lightning won the toss and elected to field. Nottinghamshire Outlaws won the toss and elected to field.
Northamptonshire won the toss and elected to field. Surrey won the toss and elected to field.
Surrey won the toss and elected to field. , Northamptonshire's innings was interrupted by rain which reduced both teams' innings to 18 overs.
The following table lists the five highest team scores in the season.
The top five highest run scorers (total runs) in the season are included in this table.
This table contains the top five highest scores of the season made by a batsman in a single innings.
The following table contains the five leading wicket-takers of the season.
This table lists the top five players with the best bowling figures in the season.
Sky Sports showed many games during 2013, after showing them throughout the 2010, 2011 and 2012 seasons. S4C also offers some coverage with a few Glamorgan matches available with Welsh commentary.
Source: Wikipedia