The closest to a red scare would be the furore regarding the Zinoviev Letter. The letter was purported to be authored by Grigory Zinoviev, a leading Bolshevik and member of the Comintern, and stated that closer ties between the Soviet Union and the current British Labour government would ensure that Leninism would infiltrate the working classes of the British Empire. The letter was published in the conservative newspaper The Daily Mail a few days before the 1924 general election and was said to have contributed to the Conservative Party's landslide victory over Labour (although in fact the Labour vote increased, mainly from defectors from the declining Liberals, though this was offset by the bigger increase in the Conservative vote).

Modern scholarship errs on the side of the letter being a forgery, though this is not proven. A. J. P. Taylor stated that even if it was a forgery, much of what it contained was in line with Zinoviev's previous statements.

The Lloyd George government intervened in the Russian Civil War on the anti-Bolshevik side and there arose in the British trade union movement a 'Hands Off Russia' agitation that objected to any British intervention. British working class opinion regarded the Bolshevik revolution as an experiment that should be left alone to see what kind of society it would create.

There was no comparable red scare to the one that occurred in America after the Great War. The Labour Party was not a revolutionary or Marxist party. It had originally grown from the trade unions and had strong links with the Liberal Party (both in personnel, ideas and electoral pacts). Although there was apprehension of what Labour would do once in power, the first Labour government in 1924 was moderate and the Labour Chancellor of the Exchequer produced a budget that was more Liberal than socialist (even the Conservative press found it difficult to fault it). All these factors contributed against a red scare.