What's the difference between ULEZ and the Congestion Charge?

The ULEZ charge (£12.50 for most vehicles) is based on your vehicle's emissions standards and operates 24/7 across all of Greater London. The Congestion Charge (£15) applies only to Central London, Monday to Friday 7am-6pm, and Saturday-Sunday 12pm-6pm, regardless of your vehicle's emissions. 

You may need to pay both charges if driving a non-compliant vehicle in Central London during Congestion Charge hours. Electric and ULEZ compliant vehicles still pay the Congestion Charge when applicable.