|British Rail Class 375 Electrostar|
|In service||2000 - present|
|Manufacturer||Adtranz / Bombardier Transportation|
Derby Litchurch Lane Works
|Refurbished||2015 - 2018|
|Number built||140 units|
|Number in service|
|Car length||20.4 m (66 ft 11 in)|
|Width||2.80 m (9 ft 2 in)|
|Height||3.78 m (12 ft 5 in)|
|Maximum speed||100 mph (161 km/h)|
|Acceleration||0.62 m/s2 (1.4 mph/s)|
|Current collection method||Contact shoe (DC) |
Pantograph (AC) (375/6 only)
|Coupling system||Dellner, 375/3, /6 & /7 units originally had Tightlock couplers when new|
|Track gauge||1,435 mm (4 ft 8+1⁄2 in) standard gauge|
The British Rail Class 375 is an electric multiple unit train that was built by Bombardier Transportation (previously Adtranz) at Derby Litchurch Lane Works, from 1999 to 2005. The class form part of the Electrostar family of units, which also includes classes 357, 376, 377, 378, 379 and 387, is the most numerous type of EMU introduced since the privatisation of British Rail.
These units form the basis of Southeastern's mainline fleet.
These trains are owned by Eversholt Rail Group (formerly HSBC Rail) and leased to Southeastern for operation from London to Kent and parts of East Sussex.
The Class 375 is the principal train used by Southeastern, and replaced the slam-door Mark 1 derived stock, which was more than 40 years old and did not meet modern health and safety requirements. All units have been converted from Tightlock to Dellner couplers.
In May 2015, unit 375301 was moved from Ramsgate Depot to Derby Litchurch Lane Works for a full refurbishment. On 16 May 2015, it was returned to the Kent depot wearing a new livery, similar to, but not based on the 'Highspeed' livery carried by the high speed Class 395 EMU, with a more vibrant shade of blue on the saloon doors and bolder stripes to highlight First Class and Disabled areas. Internally, the unit has received new carpets and lino flooring, new table top covers and the grab poles, side panels and table legs have been re-powder coated. The existing seat covers have been retained, but were dry cleaned to provide a brighter, cleaner interior. This work will also involve combining the two separate First Class sections on four car units into one section in the end of MOSL coach. It is intended for all class 375 units to receive this refurbishment between 2015 and 2018. The original plan was for the first 50 units (375/3s, 375/6s and 375/7s) to be refurbished at Bombardier in Derby and then the remaining units would be transferred for refurbishment at Bombardier Ilford. This plan did not go ahead and the 375/8s and 375/9s were sent to Derby. On 19 September 2015 the last 375/3 unit no 375310 went to Derby for refurbishment. The following week on 26 September the first 375/6 went to Derby for refurbishment. The final 375 to receive the refurbishment and gain the new blue Southestern livery was 375 920, which was returned to Ramsgate depot on 28 April 2018.
Electrostars also work the following outer suburban Southeastern routes interchangeably with Class 465/9 units:
Class 375/3 Electrostar units started operating services on the Medway Valley Line from May 2012 to January 2016, and then from September 2016 to the present day. Previously Class 466 Networkers were the regular units on this line with the occasional Class 465 Networker or 4-car 375 Electrostar being used as a substitute. The Networkers are no longer used on this route as the Class 466s are now non-compliant with the new PRM-TSI law and the volume of traffic cannot support Class 465s or 4-car Class 375s/377s.
From December 2019, Class 375/3 units replaced Class 466 units on the Sheerness line due to the latter being un-compliant with the new PRM-TSI law. 
|Class||Type||Operator||No. in traffic||Year built||Cars per unit||Unit nos.||Notes|
|Class 375/3||Express & Outer suburban||Southeastern||10||2001–2002||3||375301–310||Originally 28 units - Southern's reclassified as Class 377/3 in 2004, following fitting of Dellner couplings.|
|Class 375/6||30||1999–2001||4||375601–630||Dual voltage units.|
|Class 375/9||27||2003–2004||375901–927||3+2 seating in Standard Class and First Class at both ends of the train.|
|375 304||Medway Valley Line 1856 - 2006 (name removed)|
|375 608||Bromley Travelwise (name removed)|
|375 610||Royal Tunbridge Wells (name removed)|
|375 611||Dr. William Harvey (name removed)|
|375 619||Driver John Neve|
|375 623||Hospice in the Weald|
|375 624||White Cliffs Country (name removed)|
|375 701||Kent Air Ambulance Explorer|
|375 703||Dickens Traveller (name removed)|
|375 710||Rochester Castle|
|375 714||Rochester Cathedral|
|375 823||Ashford - Proudly Served By Rail For 175 Years|
|375 830||City of London (name removed)|
Unit 375 624 (White Cliffs Country) was re-liveried with the Southeastern trial livery and did not have its name displayed. This unit has since been refurbished with the new Southeastern blue livery.
Unit 375 610 (Royal Tunbridge Wells) previously carried a livery with royal blue doors and a gold stripe to mark the Golden Jubilee of Elizabeth II, this livery was removed upon refurbishment in January 2016, the gold stripe having been removed several years prior.