Bogus marriages have become an “industry of deceit” that is increasing at an “alarming rate”, MPs have warned.
The Commons Home Affairs Select Committee questioned whether the government knew the “scale of the problem”.
It called for more powers for registrars to stop suspicious weddings and better training to identify potential shams.
The Home Office said it was taking “ever tougher” action.
Registrars told the committee they were left presiding over what they knew to be a “charade”, and one said it was “like being mocked in your own job”.
The committee chairman, Labour MP Keith Vaz, said: “There is an industry of deceit in the UK which uses sham marriages to circumvent immigration control.
“The estimated 10,000 sham marriages appears to be increasing at an alarming rate. One sham marriage can provide UK residence rights to an entire extended family who would otherwise have no right to be here.”