Date | Section of line | Broad | Mixed |
| 1 Jan 1847 | Total mileage | 298m 13c | nil |
| 1 Jul 1847 | Yatton - Clevedon1 | 3m 45c | |
| 1 Oct 1847 | Gloucester - Cheltenham | 2m 2c | 3m 11c |
| 1 Dec 1847 | Reading - Hungerford | 22m 23c | |
| 5 May 1848 | Totnes - Laira Green6 | 21m 16c | |
| 12 Jun 1848 | Tiverton Road - Tiverton1 | 4m 60c | |
| 5 Sep 1848 | Thingley Junction - Westbury2 | 13m 54c | |
| 1 Nov 1848 | Southcot Junction - Basingstoke | 13m 49c | |
| 18 Dec 1848 | Newton - Torquay6 | 5m 1c | |
| 2 Apr 1849 | Laira Green - Plymouth6 | 2m 64c | |
| 8 Oct 1849 | Slough - Windsor | 5m 15c | |
| 18 Jun 1850 | Chepstow - Landore - Swansea3 | 74m 53c | |
| 2 Sep 1850 | Oxford - Banbury | 24m 15c | |
| 7 Oct 1850 | Westbury - Frome | 5m 61c | |
| 12 May 1851 | Exeter - Crediton5 | 5m 60c | |
| 9 Sep 1851 | Westbury - Warminster | 4m 73c | |
| 19 Sep 1851 | Gloucester - Grange Court | 7m 36c | |
| 19 Sep 1851 | Chepstow - Grange Court3 | 18m 70c | |
| 24 Sep 1851 | Neath Junction - Aberdare4 | 19m 0c | |
| 31 Dec 1851 | Total mileage | 552m 70c | 3m 11c |
| Metric conversion: 80 chains = 1 mile; 5 miles = 8 kilometres | |||
| Note 1: | Bristol & Exeter Railway | ||
| Note 2: | Wilts, Somerset & Weymouth Railway | ||
| Note 3: | South Wales Railway | ||
| Note 4: | Vale of Neath Railway | ||
| Note 5: | Exeter & Crediton Railway | ||
| Note 6: | South Devon Railway | ||
Locomotive Class | No. (+/-) | Total | |
| 1 Jan 1847 | Total locomotives | 127 | |
| Star 2-2-2 | 12 | ||
| Fire Fly 2-2-2 | 62 | ||
| Sun 2-2-2 | 21 | ||
| Leo 2-4-0 | 18 | ||
| Hercules 0-6-0 | 4 | ||
| Great Western 4-2-2 | 1 | ||
| Prince 2-2-2 | + 6 | 6 | |
| Iron Duke 4-2-2 | +22 | 22 | |
| Avalanche 0-6-0T | + 1 | 1 | |
| Premier 0-6-0 | +12 | 12 | |
| Pyracmon 0-6-0 | + 6 | 6 | |
| Bacchus 0-6-0 | + 1 | 1 | |
| Bogie 4-4-0T | + 2 | 2 | |
| B&ER 4-2-2 | +20 | 20 | |
| B&ER 0-6-0 | + 8 | 8 | |
| B&ER railcar | + 1 | 1 | |
| B&ER 2-2-2T | + 5 | 5 | |
| VofNR 4-4-0T | + 6 | 6 | |
| SDR 4-4-0T | + 4 | 4 | |
| Unclassified engines | - 1 | 8 | |
| 31 Dec 1851 | Total locomotives | +93 | 220 |
| Key: | B&ER - Bristol & Exeter Railway VofNR - Vale of Neath Railway SDR - South Devon Railway | ||