Kallas' grandfather was Eduard Alver, one of the founders of the Republic of Estonia on 24 February 1918, and the Commander of the Estonian Defence League during the Estonian War of Independence, and the first chief of the Estonian Police from 1918 to 24 May 1919.
He speaks Estonian, English, Russian, Finnish, and German.
Kallas is of Estonian and distant Baltic German ancestry.
Kallas is married to doctor Kristi Kallas, who, during the Soviet deportations from Estonia, at age six months, was deported to Siberia with her mother and grandmother in a cattle car and lived there until she was 10 years old.
He has one son and one daughter.
His daughter Kaja Kallas is the current leader of the Reform party and Prime Minister of Estonia since 2021.
1948
Siim Kallas (born 2 October 1948) is an Estonian politician, former Prime Minister of Estonia, and former European Commissioner, as well as a former member of the Communist Party of the Soviet Union.
2004
Before that he was the European Commissioner for Administrative Affairs, Audit and Anti-Fraud between 2004 and 2009.
In both Barroso Commissions he was also a Vice-President.
2010
He served as the European Commissioner for Transport between 2010 and 2014.
2014
He was twice appointed the Acting Commissioner for Economic and Monetary Affairs and the Euro in Olli Rehn's stead, from 19 April 2014 to 25 May 2014 while he was on electoral campaign leave for the 2014 elections to the European Parliament and from 1 July 2014 to 16 July 2014 after he took up his seat.
Prior to his tenure as a European Commissioner, Kallas was the Prime Minister of Estonia, Estonian Minister of Finance, Estonian Minister of Foreign Affairs, a member of the Supreme Council of the Soviet Union and a member of the Riigikogu.
Kallas is a member and former leader of the free-market liberal Estonian Reform Party and a former vice-president of Liberal International.
Kallas' inability to address some politically controversial issues such as corruption caused him to renounce his candidacy for the office of Prime Minister of Estonia in 2014.
2016
After leaving the European Commission, Kallas ran in the Estonian presidential election in 2016, but was not elected.
2017
In October 2017, he started as the municipal mayor of Viimsi Parish.
His daughter, Kaja Kallas, is the current prime minister of Estonia.