Date | Section of line | Miles/chains |
| 1 Jan 1842 | Total broad gauge mileage | 170m 66c |
| 1 Jul 1842 | Bridgwater - Taunton1 | 11m 45c |
| 1 May 1843 | Taunton - Beambridge1 | 8m 40c |
| 1 May 1844 | Beambridge - Exeter1 | 22m 23c |
| 12 Jun 1844 | Didcot Junction - Oxford | 9m 57c |
| 8 Jul 1844 | Bristol - Gloucester4 | 32m 0c |
| 12 May 1845 | Kemble Junction - Gloucester2 | 23m 9c |
| 30 May 1846 | Exeter - Teignmouth3 | 14m 78c |
| 30 Dec 1846 | Teignmouth - Newton3 | 5m 15c |
| 31 Dec 1846 | Total broad gauge mileage | 298m 13c |
| Metric conversion: 80 chains = 1 mile; 5 miles = 8 kilometres |
| Note 1: | Bristol & Exeter Railway | |
| Note 2: | Cheltenham & Great Western Union Railway | |
| Note 3: | South Devon Railway | |
| Note 4: | Bristol & Gloucester Railway | |
| |
| | Locomotive Class | Number (+/-) |
| 1 Jan 1842 | Total locomotives | 99 |
| | Fire Fly 2-2-2 | + 18 |
| | Sun 2-2-2 | + 1 |
| | Leo 2-4-0 | + 6 |
| | Hercules 0-6-0 | + 4 |
| | Great Western 4-2-2 | + 1 |
| | Unclassified engines withdrawn | - 2 |
| 31 Dec 1846 | Total locomotives | 127 |