In the UK, opposition to immigration played a key role recent successful campaign to leave the EU. A key question about attitudes toward immigrants is the extent to which opposition to a given immigrant group reflects a general rejection of the other or a more targeted response, rooted in Islamophobia, Racism or both. This work, via an experimental design included in the 8th and 9th waves of the Innovation Panel, explores intolerance toward three specific immigrant groups defined by characteristics intended to operationalize a scale of sociocultural difference by way of three characteristics: nation, race and religion. Moreover, the design acknowledges that intolerance can be masked and manipulates the extent to which anonymity is afforded participants. Three conclusions come to the forefront. First, there is clear evidence that opposition to immigration is masked. Second, Muslim immigrants are distinct in that openly expressed opposition mirrors that which is expressed under absolute and permanent anonymity. Third, there is notable stability before and after the successful Leave campaign, offering little evidence that the stigma of intolerance has lessened in the post-referendum era.