[clarification needed] In 2005 and 2006, the Bulgarian State Railways began operating Desiro trains as part of a €67 million deal with Siemens AG for a total of 25 Diesel multiple units.

The EMUs were fitted out in Varna, where BDZ and Siemens AG are intending to establish a joint venture company.

Private railway company Arriva vlaky operates with two Desiro trains borrowed from Deutsche Bahn (DB).

Because they have often replaced push/pull trains, their shorter journey times, such as on the Müglitz Valley Railway, have encouraged greater passenger numbers.

Originally DB intended to operate together modern DMUs purchased from different manufacturers, but due to software incompatibilities this proved to be impossible.

During the summer months (when fewer units are used on the Budapest suburban routes) Desiros appear on some local train diagram on the north shore of the Lake Balaton.

The 57 km (35 mi) KLIA Ekspres, an airport rail link service between Kuala Lumpur Sentral station and Kuala Lumpur International Airport to the south, uses the Desiro ET 425 M four-car electric multiple units (EMUs) (which are technically similar to DBAG Class 425 sets in Germany).

CFR Călători, Romania's national railway operator, is one of the largest users of the Siemens Desiro trainsets (as the light train variant).

They are used as commuter stopping trains on electrified lines, i.e., from Ljubljana to Koper, Jesenice (via Kranj), Maribor and Dobova (via Zidani Most).

It serves Northern San Diego County, California, United States between Oceanside and Escondido along a 35 km (22 mi) railway line.

Mountain Rail, one of two competing coalitions bidding on a large portion of FasTracks in Denver, appeared to be proposing a Siemens Desiro ML derived vehicle that is Federal Railroad Administration compliant.

By the end of December 2021 ÖBB received the last three-car cityjet Desiro ML from the framework contract for 200 vehicles in April 2010.

In August 2021 ÖBB acquired 21 additional four-car cityjet Desiro ML trains with eight doors per side and more than 290 seats.

In August 2014 the head of the NMBS/SNCB explained to the newspapers that the Desiro trains need repairing too often, i.e., at a rate of one technical intervention per 8000 kilometers.

Desiro ML Mittelrheinbahn is used by the private rail operator trans regio for regional services between Cologne and Mainz on the left bank of the Rhine.

Desiro RUS, designated ES1, is a 1,520 mm (4 ft 11+27⁄32 in) broad gauge electric commuter and regional train developed for Russian railways, which calls them Lastochka (English: Swallow).

In mid-2013 a joint venture between Siemens and Ural Locomotives began production of the second batch of 16 trains at a factory in Ekaterinburg.

A further modification with variable length train sets, from 4 to 12 cars, and local asynchronous power unit called ES104 (Finist), which began its operation at the end of 2023 in Yekaterinburg.

The trainsets have modern equipment such as toilet waste retention tanks, ergonomic seats, and automated information displays with spoken announcements.

[19] The only significant difference from the UK units is a much larger air conditioning pod on the roof, providing extra cooling to cope with the Thai climate.

[21] The first Desiro UK units were ordered by South West Trains in 2001 for both short- and long-distance service out of London Waterloo to Alton, Basingstoke, and the Hampshire/Dorset coast, to replace its Mark 1 slam-door EMUs, which were due for replacement by the end of 2005 as they were more than 40 years old and did not meet modern health and safety requirements.

[24][25][26] First Great Eastern acquired 21 Class 360/1 four-car units which operate from 25 kV overhead electrical supply for services from London Liverpool Street to Clacton-on-Sea and Ipswich.

[34][35] As part of the modernisation of the West Coast Main Line, the Strategic Rail Authority (SRA) ordered 30 Class 350 dual-voltage sets for use on stopping services by Central Trains and Silverlink.

In 2003 First TransPennine Express ordered diesel-powered Desiro UK trains for use on its inter-city services across the north of England and to southern Scotland.

[42] A £1.6 billion order for 115 eight-car and twelve-car units (1,150 vehicles) for the Thameslink rolling stock programme was awarded in 2011 and finalised in 2013.

[49] In April 2015, Siemens announced that it had won a tender[50] to build a fleet of 82 Desiro HC trains for the Rhein-Ruhr-Express (RRX) project in Germany.

In September 2017, Israel Railways announced that Siemens was the successful bidder in a tender for 60 Electric Multiple Unit sets (for a total of 330 carriages) to be delivered starting in 2021.