The lower house of British Parliament had a two-hour debate then approved the final changes to a bill legalizing same-sex marriage in England and Wales.
The bill, passed in the House of Lords on Monday (15 July), only now must be signed by Queen Elizabeth II to become law. This is considered to be a formality.
Culture Secretary Maria Miller said: 'The title of this bill might be "Marriage" but its fabric is about freedom and respect.'
The marriage bill has the backing of Prime Minister David Cameron but his Conservative Party was split in its support. Britain's two other main political parties, Labour and the Liberal Democrats, both support the bill.
Gay couples had previously been able to obtain only civil partnerships in Britain.