The West End Riots (sometimes referred to as the Trafalgar Square Riots and the Pall Mall Riots) occurred in London on February 8, 1886, after two groups on opposite sides of workmen’s rights and trade issues had held simultaneous rallies in Trafalgar Square. It was recognized that the groups might clash violently, but there had been no serious public order problems in London since the Hyde Park Riot in 1866, and the British Home Secretary was preoccupied with Irish Home Rule. As a result, authorities did not order serious precautions.

The meetings themselves occurred without incident, but when the speakers left the square a crowd estimated in some press accounts to be as high as 100,000 streamed west along Pall Mall and resumed a meeting in Hyde Park. Due to misinformation, the Metropolitan Police believed that trouble would occur in The Mall instead of Pall Mall, so they marched away to protect Marlborough House and Buckingham Palace. A few hundred meters north the mob rushed unhindered along Pall Mall and St James's, famously smashing the local club windows along the way.

Inquiries following the events of February 8 were critical of the actions of the Metropolitan Police on the day—including their interruption of a speaker attempting to make a speech in front of Nelson’s Column—and the Commissioner of the Metropolitan Police resigned two weeks after the riots.