Some former JR East sets were also sold for second hand use in Indonesia, where they operated on the KRL Jabodetabek system in Jakarta between 2004 and 2016.

JR East has previously operated a large number of 103 series sets on the following lines.

A single four-car 103 series set remained in use by JR East on the Senseki Line in the Sendai area between November 2006 up until 21 October 2009.

JR-West continues to operate a large number of 103 series sets, many of which have received extensive life-extension refurbishment.

Four former JR East 103 series 4-car units (Musashino Line sets KeYo 20, 21, 22, and 27) were shipped to Indonesia in 2004 to operate on the KRL Jabodetabek system in Jakarta.

The 103 series was the main rolling stock used on urban commuter services for a time.

Some sets have been used for at least 50 years, and their age is starting to show; as such, their use on various lines is diminishing and they are being replaced by newer trains.

Cars fitted with TR212 bogies feature disc brakes, because they needed to run on higher speeds on the Jōban and Hanwa Lines.

It was equipped with various air conditioning units and tested on the Yamanote Line in Tokyo.

The front end design was changed with the driver's cab raised so that an ATC signalling system could be included.

The cars' bodies and bogies were 101 series originals as the conversions involved minimum modification.

The direct-drive motors and IGBT inverters appear to be of the same specification as used on the experimental E993 series set due to similar cadences.

No JR train since (other than the E993 and E331 series sets) has used direct-drive motors in combination with IGBT inverters.

160 103–1000 series cars (formed 16 10-car sets) were built in 1970 and 1971 for use on Jōban Line-Chiyoda Line inter-running services, which commenced in 1971.

Originally painted in grey with a sea green stripe, they were subsequently displaced by new 203 series trains.

They were initially painted in light blue with a white stripe, but were repainted into a grey and red livery from 1995.

[12][4] Eight 2-car 103–3550 series refurbished sets (M1 to M8) were formed between January and October 2004 ahead of Kakogawa Line electrification in March 2005.