The Coalition followed in the footsteps of the Scottish Government by revealing plans for the rest of the UK.
Culture Secretary Maria Miller said the plans would ensure "equal and fair treatment" for same-sex couples, while protecting religious institutions that do not want to perform ceremonies.
But the Bill is set to encounter fierce resistance from a significant number of Tory MPs.
Mrs Miller said: "In opening up marriage to same-sex couples, we will further strengthen the importance of marriage in our society."
The measures would also allow civil partners to convert their partnership to a marriage, and enable married people to change their legal gender without having to end their union.
MPs will have their first chance to vote on the plans when the Marriage (Same Sex Couples) Bill has its second reading in the House of Commons on Tuesday, February 5.
David Cameron has attempted to head off a rebellion by giving Conservative MPs a free vote.
The Bishop of Leicester, the Rt Rev Tim Stevens, said he was grateful to Mrs Miller for the "constructive" way in which she has consulted with the Church of England on the issue of effective legal safeguards.
Yvette Cooper, shadow home secretary and shadow minister for women and equalities, said: "Couples who love each other and want to make a long-term commitment should be able to get married, whatever their gender or sexuality."
Scotland is likely to become the first part of UK to introduce gay marriage after the SNP Government announced plans.
Ministers confirmed they would bring forward a bill on the issue, indicating the earliest ceremonies could take place by the start of 2015. The move has been strongly opposed by the Catholic Church and the Church of Scotland.