He joined the right of centre
United National Party, serving as its treasurer and entered parliament from the National List at the 2010 General Elections. After the election of
Maithripala Sirisena, Wickramaratne was appointed as the Deputy Minister of Investment Promotions and Highways in the "good governance" government under the premiership of
Ranil Wickremasinghe. He was appointed as the United National Party chief organiser of the Colombo-East electorate before being shifted to the
Moratuwa electorate in 2015. In the
general election that followed he was elected to parliament from the Colombo district gaining 82,737 votes. In 2015, he was appointed Deputy Minister of Investment Promotions and Highways and in 2017 he was appointed State Minister of Finance, holding office until the appointment in 2019 of a new caretaker cabinet headed by
Mahinda Rajapaksa. ==Sri Lanka Cricket==