On all Tehran metro trains the first and half of the second carriages from each end are reserved for women.

[11] Initial plans for the metro system were laid in late 1960s but could not be executed until 1982 because of socio-political issues such as the Iranian Revolution and the Iran-Iraq War.

The French company SOFRETU, affiliated with the state-owned Paris transportation authority RATP, won the tender and in the same year began to conduct preliminary studies on the project.

In 1978, construction on the line was started in northern Tehran by the French company, however this development was short-lived with the advent of the Iranian Revolution and Iran–Iraq War in 1979 and 1980 respectively.

On March 3, 1982, the Iranian Cabinet ministers formally announced the stop of Tehran Metro operations by the French company.

In 1985, the "Tehran Metro Execution Plan" was re-approved by the Majiles, the Iranian Parliament, on the basis of legal project of "Amendment of Law of Establishment of Tehran Urban and suburban Railway Company" which had been founded on Farvardin 1364 (April 1985).

By the summer of 1985, urban pressure from the rapidly urbanising population, and lack of developed public transport system prompted the work to be resumed in earnest.

Shahid Ayatollah Haghani to City of Rey) and its extension to Behesht-e-Zahra Cemetery was made a priority.

It was decided that an organisation by the name of the Metro Company should be established in order to handle the future development of the system.

The Metro Company then became managed by Asghar Ebrahimi Asl for eleven years.

During that time, hundreds of millions of dollars were spent on the system and the Metro Company was given government concessions for the exploitation of iron ore mines in Bandar Abbas (Hormuzgan Province), exploitation and sale of Moghan Diotomite mine in the Iranian region of Azarbaijan,[12] export of refinery residues from Isfahan oil refinery as well as tar from Isfahan steel mill.

On 7 March 1999, an overland Tehran-Karaj express electric train started a limited service of 31.4 km (19.5 mi) between Azadi Square (Tehran) and Malard (Karaj) that called at one intermediate station at Vardavard.

The Metro uses equipment manufactured by a wide range of international companies: double-deck passenger cars for the Tehran-Karaj regional line are supplied by CRV (although some trains are from SEGC) via CNTIC and assembled by the Wagon Pars factory in Arak.

New 80 wagons have been added to the system in September 2012 to ease transportation and reduce rush-hour congestion.

[17] A 31-kilometre (19 mi) express line to Imam Khomeini International Airport was opened in August 2017.

[19] Line 1, coloured red on system maps, is 86.9 kilometers (54.0 mi) long, of which 14.9 km (9.3 mi) are underground (from Tajrish station to Shoush-Khayyam crossing) and the rest runs at surface level.

As of 2018[update], the total capacity of line 1 is 650,000 passenger per day, with trains stopping at each station for 20 seconds.

It has also faced major financing issues as the government has refused to release funds earmarked for the project to the municipality.

Its 120 km (75 mi) per hour speeds classify it as an express subway line, the first of its kind on the Tehran Metro.

The construction of a western extension to line 4 has been started in 2012 connecting Ekbatan to Chaharbagh Sq.

[28] An initial 9-kilometer-long (5.6 mi) section between Shohada Square to Dowlat Abad opened on April 7, 2019.

When completed, this line will be 38 km (24 mi) long with 31 stations, connecting southeast Tehran to northwest.

TBM is using earth pressure balanced method to pass safely through urban areas without considerable settlement.

In the south, line 3 will continue for 10.5 km (6.5 mi) from the terminus Azadegan with five new stations to Eslamshahr.

On 18 July 2007, a twenty square metres area immediately adjacent to the entrance of the Toupkhaneh metro station caved in.

On 15 April 2012, safety walls of Mianrood River broke due to heavy rain in Tehran, and consequently, 300,000 cubic meters of water entered metro tunnel of Line 4.

[46] The Cultural Heritage Organization of Iran has complained that the vibrations caused by the Metro were having a significant and highly adverse effect on the Masoudieh Palace in the Baharestan neighbourhood of central Tehran.

[47] The Cultural Heritage Organisation has also complained about vibrations near other historic sites such as the Golestan Palace and the National Museum of Iran.