List of British politicians who have crossed the floor

Members of the House of Commons of the United Kingdom, British members of the European Parliament, and members of the British devolved assemblies sometimes cross the floor and abandon a previous party membership to take up a new one. The following list details the dates, members involved, previous and new party affiliations, and an explanation for their switch. In addition, this list notes MPs who have lost or resigned a party whip to become independent, or moved from being independent to taking a party whip.

Formed new party

These MPs were suspended by their Parliamentary Parties but continued to receive the Whip.

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