Billström became a Member of the Riksdag 2002 following Swedish election, he then became a deputy in the Education Committee, Employment Committee and in the Cultural Committee. In 2003, he became a member of the Education Committee where he received a special responsibility for issues related to higher education and research. In April 2005, Tobias Billström became a member of the Social Security Committee and Moderate Party spokesperson on issues related to migration and integration. During the period from 2003 to 2007, Billström was Chairman of the Moderate Party in Malmö. Billström became a member of the board of the Swedish Migration Board in November 2005, a position he left when he was appointed Minister in 2006. Billström participated as a Member of the Riksdag in the discussion of migration policy. He opposed the temporary asylum law that was implemented by the social democratic Persson cabinet, arguing that the law was not fair and that it was based on collective judgment.
The Reinfeldt Cabinet set a new target for the Swedish migration policy after it took office in October 2006, which was to increase the opportunities for labour immigration. Tobias Billström has emphasised the importance of creating a balance in the policy area where asylum issues often dominate. He also pointed out that labour immigration today is a way to help developing countries beyond the traditional aid.
Re-establishment support
The government implemented, on 1 August 2007, a re-establishment support to facilitate the repatriation of those who have had their asylum applications rejected.
Middle East
Tobias Billström has promoted that countries in Europe and the world should help refugees from Iraq. He has emphasised the need for a very strong common asylum and migration policy, and that this could give more Iraqis in need of protection to access this. The work was given a start with the article that Billström wrote with Cecilia Malmström in the Swedish newspaper Svenska Dagbladet. The message has since been represented to the Council of the European Union and at several international conferences where Billström represented Sweden, including in Geneva and in Sharm el-Sheikh. From 30 March until 4 April 2007, Tobias Billström, as the first European Minister for Migration and Asylum Policy, made a trip to Syria and Jordan to create a picture of the situation of the Iraqi refugees residing there. At the time he was interviewed in Damascus by Sveriges Radio. In classified documents revealed by wikileaks, Tobias Billström together with Carl Bildt mentioned in their 2007 visit to Baghdad for the American AmbassadorRyan Crocker the Iraqi refugee situation in Sweden, in specific the reports entail the ministers mentioning honour killings and the Swedish opinion of restricting immigration.
Controversial statements
In an interview about illegal immigrants hidden in Sweden on 18 March 2013, Billström said that "Sometimes we have the impression that the person who is hidden lives with a nice blonde Swedish lady in around the age of 50 to 60 who wants to help. But that's not true. Most people live with their compatriots who is not blond and blue-eyed." The statement was severely criticised by both opposition parties as well as the other governing parties in the Alliance coalition government. The leader of the Moderate Youth League, youth league of the Moderate Party, Erik Bengtzboe also criticised the statement and called for Billström to apologise and to think about what he says. Some even called for Billströms resignation from the position as Minister for Migration and Asylum Policy. The right wing Sweden Democrats party leader Jimmie Åkesson welcomed Billströms statement and said "that he was on the right track". In the early afternoon on the same day, Billström officially apologised for his statement and said that his words came out in the wrong way, and that what he said was not what he really meant. Fredrik Reinfeldt, the Prime Minister of Sweden, welcomed Billströms apology.
First Deputy Speaker
Billström was elected First Deputy Speaker on 29 September 2014. He resigned from the position in October 2017, to become Moderate Party leader in the Riksdag.
At the age of, Billström is the second youngest member of the cabinet, after Annie Lööf. He is also the first openly bisexual person to serve as minister in a Swedish cabinet. He is married to Sofia Åkerman with whom he has one daughter.
TV license controversy
On 11 October 2006, less than a week after he took office, it was revealed that Billström deliberately had neglected to pay his television licence for ten years, despite owning a television. Billström stated that his neglect was based on his political standpoint against public service, but that he had come to appreciate public service and that he believed that citizens and especially legislators should follow the law. Billström also expressed his ambition to repay his debt with interest. However, on 12 October 2006, Radiotjänst i Kiruna AB, a private agency tasked with collecting the license fees, filed criminal charges against Billström together with two other ministers in the Reinfeldt Cabinet: Cecilia Stegö Chilò and Maria Borelius, with the latter two resigning on 14 and 16 October 2006. Billström has stated that he intends to remain in office and has no intention of resigning.