Cyril Patrick Mahon (9 September 1882 – 14 July 1945) was a British banker who served as Chief Cashier of the Bank of England from 1925 to 1929 and comptroller of the Bank from 1929 to 1932. Mahon was succeeded as Chief Cashier by Basil G. Catterns. Mahon was born in Leigh-on-Mendip, Somerset, the son of village vicar Rev. George Augustus Mahon. He was educated at All Saints School, Clifton, and at All Saints School, Bloxham, Oxfordshire.