Kirkby has been represented at the Houses of Parliament by George Howarth since 1986 first as part of the Knowsley North constituency, then as part of the Knowsley North and Sefton East constituency and since 2010 as part of the Knowsley constituency. He currently holds a 44,374 majority, which makes it the safest Labour seat in the country. He was preceded by Robert Kilroy-Silk, Labour (1974–1986), Harold Soref, Conservative (1970–1974) and Harold Wilson, Labour (1950–1970), although the representing constituency has varied due to regularly shifting boundaries. The boundaries will change once again at the next general election.