Non-compete agreements (or any clause restricting working elsewhere) are generally not enforceable in UK zero-hours contracts. Explicitly since January 2016, an

Non-compete agreements (or any clause restricting working elsewhere) are generally not enforceable in UK zero-hours contracts. Explicitly since January 2016, and in practice before then.[1] [1] https://www.gov.uk/government/publications/zero-hours-contracts-guidance-for-employers/zero-hours-contracts-guidance-for-employers https://www.gov.uk/government/publications/zero-hours-contra... (Bottom para.)