When did the UK stop using the Half-pence?

Answer 1

The original, pre-decimalised half-pence was withdrawn from circulation in 1969,a and not replaced until 1971, on the day of decimalisation. The modern, decimalised half-pence was last minted en masse in 1983 and withdrawn at the end of that year, by which time its annual minting had fallen from a high of over 350million in 1972 (discounting the initial run) to less than 10million coins in 1983, due to the effective worthlessness of the half-penny by the 1980s.