He stood for Parliament at the February 1974 general election in Rugby but lost by 6,154 votes to Labour's William Price.

Boswell was chosen to contest the Daventry constituency after the sitting Conservative MP Reg Prentice announced his retirement.

Tim Boswell's Westminster career began unsurprisingly as a Member of the Agriculture Select committee in 1987.

In December 1992, Tim Boswell was appointed Parliamentary Under Secretary of State at the Department of Education and moved in the same position at the Ministry of Agriculture, Fisheries and Food until the Major government fell at the 1997 general election.

On 31 March 2006, Boswell announced his intention not to contest the subsequent general election, provided it did not take place unexpectedly soon.