Simultaneously, a vacancy occurred in the Westland North parliamentary electorate through Timothy Gallagher's resignation and on 1 June 1860, Kynnersley advertised his candidacy. He stood as an independent, but supporting the Fox Ministry in their stance on the New Zealand War. He also advocated for the abolition of the provincial government system. Kynnersley was unopposed in the resulting 2 July by-election and represented the electorate until the dissolution of the 4th Parliament on 30 December, when he retired.