The 24-year-old rejected a new deal with Braintree after scoring 24 times in 55 appearances, due to his desire to make the step up to the Football League.
"Dan gives us another option in the forward areas of the pitch," Colchester boss Joe Dunne told the official club website.
Holman scored 29 goals in the Conference North for Histon before signing for Braintree in the summer of 2012.
Restore Data
| Team | P | W | D | L | F | A | GD | PTS | |
| 1 | Gillingham | 8 | 6 | 1 | 1 | 12 | 2 | 10 | 19 |
| 2 | Walsall | 8 | 6 | 0 | 2 | 15 | 4 | 11 | 18 |
| 3 | BarrowBarrow | 8 | 5 | 1 | 2 | 11 | 5 | 6 | 16 |
| 4 | Notts County | 8 | 4 | 3 | 1 | 15 | 8 | 7 | 15 |
| 5 | Port Vale | 8 | 4 | 2 | 2 | 13 | 11 | 2 | 14 |
| 6 | AFC Wimbledon | 6 | 4 | 1 | 1 | 9 | 4 | 5 | 13 |
| 7 | Doncaster RoversDoncaster | 8 | 4 | 1 | 3 | 11 | 12 | -1 | 13 |
| 8 | Crewe AlexandraCrewe | 8 | 4 | 1 | 3 | 8 | 9 | -1 | 13 |
| 9 | Chesterfield | 8 | 3 | 3 | 2 | 13 | 6 | 7 | 12 |
| 10 | Fleetwood TownFleetwood | 7 | 3 | 3 | 1 | 10 | 7 | 3 | 12 |
| 11 | Grimsby Town | 8 | 4 | 0 | 4 | 12 | 14 | -2 | 12 |
| 12 | Newport CountyNewport | 8 | 4 | 0 | 4 | 12 | 16 | -4 | 12 |
| 13 | Bradford CityBradford | 8 | 3 | 2 | 3 | 10 | 9 | 1 | 11 |
| 14 | Harrogate TownHarrogate | 8 | 3 | 1 | 4 | 8 | 11 | -3 | 10 |
| 15 | Colchester UnitedColchester | 8 | 2 | 3 | 3 | 12 | 14 | -2 | 9 |
| 16 | Salford City | 7 | 2 | 3 | 2 | 4 | 6 | -2 | 9 |
| 17 | Tranmere RoversTranmere | 7 | 2 | 3 | 2 | 3 | 7 | -4 | 9 |
| 18 | Bromley | 8 | 2 | 2 | 4 | 10 | 12 | -2 | 8 |
| 19 | MK Dons | 8 | 2 | 2 | 4 | 7 | 10 | -3 | 8 |
| 20 | Cheltenham TownCheltenham | 8 | 2 | 1 | 5 | 9 | 13 | -4 | 7 |
| 21 | Swindon TownSwindon | 8 | 1 | 3 | 4 | 8 | 12 | -4 | 6 |
| 22 | Carlisle UnitedCarlisle | 8 | 2 | 0 | 6 | 10 | 17 | -7 | 6 |
| 23 | Morecambe | 8 | 0 | 3 | 5 | 6 | 11 | -5 | 3 |
| 24 | Accrington StanleyAccrington | 7 | 0 | 3 | 4 | 8 | 16 | -8 | 3 |
| > League Two Full Table | |||||||||
