The Union of Orthodox Hebrew Congregations has welcomed a court ruling which may force the government to ease restrictions on marriage visas.
Two years ago, new rules were introduced to refuse entry for spouses from outside the European Union if they or their British spouse were under 21.
But the change hit the Charedi community, where people marry young and often choose partners from Israel or the USA.
The Court of Appeal has now called into question the whole policy - which was designed to combat forced marriages - after upholding appeals on behalf of two non-Jewish couples.
Presiding judge Lord Sedley said the "arbitrary and disruptive impact of the rule on the lives of a large number of young people makes it impossible to justify, at least where one spouse is a United Kingdom citizen, notwithstanding its proper objective".
Chanoch Kesselman, executive co-ordinator of the Union, which made a submission to the court on behalf of the appellants, said the community was "very pleased" with the decision.
He said the law as it stood was "unfair to the Charedi community and others, since it breached the civil liberties of Jews under the age of 21 to marry a partner of choice and live in the UK.
"We look forward to the law being changed without further delay."
The case was brought on behalf of Diego and Amber Aguilar, and Suhayl Mohammed and Shakira Bibi.
Mr Aguilar, 20 from Chile, met his wife Amber while studying in Britain and they married in 2008 when she was 17. But they were forbidden to live here after his student visa expired.
Mr Mohammed, 20, a UK citizen, married his wife Shakira in Pakistan two years ago when she was 18. There was no suggestion the marriage was forced, Lord Sedley said, but the "couple are still apart".
Immigration Minister Damian Green said he was disappointed by the decision, and the government planned to appeal. Mr Kesselman's submission pointed out "Jews are encouraged to marry from 18, and the test of time has shown marriages within the Jewish community are successful".