The election was won comfortably by the Conservative candidate John Howell with an increased percentage of the popular vote. The governing Labour Party's vote fell by 11% and they finished fifth, losing their deposit.
Henley was considered a safe seat for the Conservative Party—having been held by the party continuously since 1910 up to this election. Johnson had gained a 12,793 majority from the Liberal Democrats at the previous election, though recent local elections have seen the Liberal Democrats' vote rise. Despite this, an easy win for the Conservative Party candidate was predicted, with the Labour Party being given little to no chance of victory. It had been expected that the by-election would be held after the parliamentary summer recess. However, following their victory in the Crewe and Nantwich by-election, the Conservatives took the opportunity to bring the by-election forward to 26 June, in order to capitalise on their strong support.