István Tarlós was born in an intellectual family on 26 May 1948 in Budapest, Hungary.
He graduated from Árpád High School in classical studies in 1966 with a good qualification level. Following a deferred admission at the university, he first worked as an unskilled labourer for a year; then he did military service in Orosháza for another year. He studied at the Budapest University of Technology for three years and then at the Transport and Telecommunication Technical College. There he obtained a civil engineer degree in 1973. Afterwards he post-graduated in economics and organization at Ybl Miklós Technical College with an excellent qualification level. During his 15-year civil engineer career spent in the construction industry, his jobs have mainly included investor and contractor tasks. For a few years preceding the change of regime, he managed his own architect studio with his wife Cecília Nagy.
He was neither member of MSZMP (Hungarian Socialist Workers’ Party), nor member of the Workers’ Militia, nor an agent. Tarlós first entered politics by becoming a member of SZDSZ (Alliance of Free Democrats) in 1989. As the common candidate of SZDSZ and FIDESZ (Alliance of Young Democrats), he became Mayor of District III Budapest, Óbuda – Békásmegyer for the first time, in October 1990. In the summer of 1994, he decided to quit SZDSZ after the party entered into coalition with MSZP (Hungarian Socialist Party). Then, as an independent candidate, supported by FIDESZ and KDNP (Christian Democratic People’s Party), he was continually re-elected with great majority as Mayor of Óbuda – Békásmegyer, in 1994, 1998 and 2002. Through the assignment of Budapest district mayors, he became their representative in the Central-Hungarian Regional Development Council, where he held the position of vice-chairman for four years and at the same time he was the head of the Commission for Regional Strategic Planning.
In 2006, he participated in the mayoral election of Budapest City with the support of FIDESZ-KDNP, when he got only 1.6 per cent difference behind Gábor Demszky, the common candidate of SZDSZ and MSZP.
Tarlós, still as independent but declared conservative politician belonging to the FIDESZ‐KDNP Fraction‐Alliance, as the leader of the opposition was leading the FIDESZ Fraction as well as the FIDESZ‐KDNP Fraction‐Alliance in the Municipality of Budapest from October 2006 till October 2010. Besides his role as fraction‐leader, Tarlós led the successful "Social Referendum 2008" campaign, initiated by FIDESZ‐KDNP Fraction‐Alliance.
Tarlós, supported by the FIDESZ-KDNP Alliance, won the municipal elections in October 2010 and became the Mayor of the City of Budapest. He was re-elected as the Mayor of Budapest at the municipal elections on 12 October 2014.
For his work as a mayor, Tarlós has been awarded with several state and civil medals, as well.
He is married, has three children and six grandchildren.