She was a Member of the European Parliament (MEP) for the South East England region of the United Kingdom from 2005 to 2014.

She was nominated for a life peerage in the 2015 Dissolution Honours and was created Baroness Bowles of Berkhamsted, of Bourne End in the County of Hertfordshire, on 23 October 2015.

She was also a member of the European Parliament's delegation for relations with the countries of South East Asia and ASEAN.

Shortly thereafter Bowles was elected chairwoman of the Committee on Economic and Monetary Affairs, succeeding Pervenche Berès.

Bowles was re-elected chairwoman of the Economic and Monetary Affairs Committee in January 2012 and served in this role until the end of the parliamentary term in 2014.