Scientologists Louisa Hodkin and Alessandro Calcioli had put the ceremony on hold after a High Court judge said services run by Scientologists were not “acts of worship”.
But the Supreme Court yesterday overturned that decision and ruled that the Scientology church was a “place of meeting for religious worship”.
Ms Hodkin took legal action after the registrar general of births, deaths and marriages refused to register the London Church Chapel for the solemnisation of marriages under the 1855 Places of Worship Registration Act, because it was not a place for “religious worship”.
Five Supreme Court justices upheld Ms Hodkin’s challenge after analysing the issue at a hearing in London in July.
Judges said religion should not be confined to faiths involving a “supreme deity”.
They said the Church of Scientology held religious services; therefore its church was a “place of meeting for religious worship”.
In 1970, the Church of Scientology launched a similar case. Then the Court of Appeal ruled that Scientology did not involve religious worship because there was no “veneration of God or of a supreme being”.
Ms Hodkin argued that the 1970 ruling should not be binding because Scientologist beliefs and services had evolved during the past four decades. She said services were “ones of religious worship” and likened Scientology to Buddhism and Jainism.
She said she was “really excited” by the ruling. “I wanted to be treated like any other religious person,” said Ms Hodkin, a church volunteer. “I want to get married in my own church. It’s a human rights issue.”
Mr Calcioli, a graphic designer, said he was “ecstatic” and went on: “I think the court’s definition of religion is excellent. I think it’s what most people today would understand religion to be.”
The couple, both 25 and from East Grinstead, West Sussex, said they aimed to marry in the next few months but had yet to set a date.
Government ministers at Westminster have raised concerns and say the ruling has tax implications. Communities secretary Eric Pickles welcomed the earlier High Court ruling.
Mr Pickles previously said the Church of Scientology might have been entitled to tax breaks – because of rules governing places of public worship – if a decision had gone in its favour.
He said taxpayers would not want “such a controversial organisation” to get special treatment.
And yesterday local government minister Brandon Lewis said his department would be taking legal advice as a result of the Supreme Court ruling.
“I am very concerned about this ruling and its implications for business rates,” he said.
“In the face of concerns raised by Conservatives in opposition, Labour ministers told Parliament during the passage of the Equalities Bill that Scientology would continue to fall outside the religious exemption for business rates.
“But we now discover Scientology may be eligible for rate relief and that the taxpayer will have to pick up the bill.”
He added: “Hard-pressed taxpayers will wonder why Scientology premises should now be given tax cuts when local firms have to pay their fair share.”
Andrew Copson, chief executive of the British Humanist Association, said: “In an open society, it’s difficult to see why the adherents of one religion should be denied the same rights granted to adherents of another.
“Those who find today’s ruling uncomfortable should turn their focus on the problem of religious privilege in England in general, which encourages the sort of ‘levelling up’ rulings we see today and often.”