Supporters of the bill in Parliament's upper house wore pink carnations Monday as the Lords agreed to send it back to the House of Commons, where lawmakers will review government amendments before it becomes law.
That is expected to go without a hitch, as the House of Commons earlier passed the bill 390 to 148.
The bill will enable gay couples to get married in both civil and religious ceremonies in England and Wales, though the Church of England, which is divided on the issue, is barred from offering same-sex ceremonies.
Currently, same-sex couples can form civil partnerships, which carry similar rights and responsibilities to marriage.
Copyright 2013 The Associated Press.
Photo: Crowds in Trafalgar Square at the Pride London gay pride parade The London Pride Parade 2013, London, Britain - 29 Jun 2013 This year's theme is Love (and Marriage), celebrating not only the achievement of equal marriage in the UK, as well as in various countries around the world, but also the love and support that exists within the LGBT (lesbian, gay, bi(sexual) and trans(gender), community and their friends and families.