Class 158 'Super Sprinter' (11 units)
Diagrams (SX): 5 diagrams (SX)
Routes operated: Salisbury to Romsey via Redbridge and Swaythling
Capacity: 114 standard in 2+2 formation, 13 first in 2+2 (127 total)
Location of first class: Situated at one end of the train
Length: 2 23m long coaches

These units are small long distance coaches, and can be found on Salisbury to Romsey via Southampton Central shuttles, as well as some Southampton Central to Portsmouth Harbour shuttles.

Class 159 'Super Sprinter' (22 /0 units, 8 /1 units)
Diagrams (SX): 24 diagrams (SX)
Routes operated: All West of England line services (including Bristol)
Capacity: 172 standard in 2+2 formation, 23 first in 2+2 (195 total)
Location of first class: Normally at London end of unit
Length: 3 23m long coaches

Although not strictly on the SWML, the class 159s operate the West of England line services between London and Bristol, Exeter, Paignton & Plymouth.

Class 421 3-CIG (2 units, based at Bournemouth depot)
Diagrams (include ECS timings): SuX, SuO
Routes operated: Brockenhurst to Lymington Pier
Capacity: 128 standard in 3+2, 36 first in compartments (164 total)
Location of first class: Either end of the train
Length: 3 20m long coaches

Preserved by South West Trains and refurbished at Wimbledon Park depot, these units operate the community line between Brockenhurst and Lymington Pier.

Class 444 'Desiro' (45 units)
Diagrams (SX): 41 diagrams
Routes operated: London to Weymouth, London to Poole
Capacity: 299 standard in 2+2 formation, 35 first in 2+1 (324 total)
Location of first class: Closest towards London end of train
Length: 5 23m long coaches

These units are the primary units on the London to Weymouth route, as well as covering routes into Portsmouth Harbour additionally. These units replaced the class 442 'Wessex Electric' units on the route.

Class 450 'Desiro' (127 units, some 'HiDensity')
Diagrams (SX): First 45 (low density), remaining 45, rest coming soon
Routes operated: London to Poole, some services to Weymouth
Capacity: 246 standard in 3+2 formation, 24 first in 2+2 (270 total)
Location of first class: 2nd coach towards London end of train
Length: 4 20m long coaches

These units are primarily for short distance suburban work, however they may be formed of a longer train (ie, London to Poole). On London to Poole services, a change will generally result in a faster journey time.

Class 458 'Juniper' (30 units)
Diagrams (SX): 25 diagrams
Routes operated: London to Reading and Aldershot, Guildford to Ascot
Capacity: 250 standard in 3+2 formation, 24 first in 2+2 (274 total)
Location of first class: Located either end of 4-coach unit.
Length: 4 20m long coaches

These units are based at Wimbledon Park depot although mostly are outstabled overnight. These units replaced slammers, and then class 450s, on the Reading suburban lines.

Class 220 'Voyager' (34 units + 24 5-car tilting 'Super Voyagers')
Routes operated: Bournemouth - Reading - the north
Capacity: 162 standard in 2+2 formation, 26 first in 2+1 (188 total)
Location of first class: Located by yellow strap on buffer beam, either end
Length: 4 23m long coaches

These units are long distances units and operate Arriva's CrossCountry services between Bournemouth and the north (primarily Manchester from December 2008).