Christian Susanne Wilkinson lost her appeal against a ruling that she unlawfully discriminated against a gay couple when she refused to let them stay in a double room.
She refused to let Michael Black, 64, and partner John Morgan, 59, have the room at the Swiss Bed and Breakfast in Cookham, Berkshire, in March 2010.
A judge at Reading County Court heard that the pair, from Brampton, near Huntingdon, Cambridgeshire, who had made a reservation and paid a deposit, protested at their treatment but Mrs Wilkinson made it clear that it was against her religious convictions to allow two men to share a bed.
Master of the Rolls Lord Dyson, Lady Justice Arden and Lord Justice McCombe, in the Court of Appeal in London, dismissed Mrs Wilkinson's challenge, but gave her permission to appeal to the Supreme Court.
More top news
Labour's Chuka Umunna urged his party to unite around its new leader in an apparent offer of reconciliation to left-winger Jeremy Corbyn.
Britain's ugliest building is the Walkie Talkie in London, according to a public vote.
Britain's stance over taking in more refugees could hurt David Cameron's EU reform plans, a spokesman for Angela Merkel's alliance has said.