Britain First's heads have been charged with religious harassment.
Leader Paul Golding, 35, and deputy Jayda Fransen, 31, were initally taken into custody on May 10 and were charged on Wednesday, Kent police said.
They are bailed and due to reappear before Medway Magistrates Court on October 17.
'The investigation related to the distribution of leaflets in the Thanet and Canterbury areas, and the posting of online videos during a trial held at Canterbury crown court the same month,' Kent police said.
Their arrest was linked to a then ongoing trial of four men suspected of gang rape in a flat in Ramsgate.
The trial involved three Muslim men and a teenager, who were eventually convicted of rape and jailed.
Fransen has been charged with four counts of causing religiously aggravated harassment and Golding with three counts.
In a separate case the former leader of the English Defence League Tommy Robinson was given a suspended prison sentence for contempt of court after filming outside the court building during the same rape trial in May.
In a video posted online Robinson described the defendants, who had not yet been convicted, as 'paedophiles'.