Over the years we've clocked up thousands upon thousands of cold, dark winter road miles to test hundreds of rear lights. These are the best rear bike lights you can buy, from brilliant budget beamers to retina-ripping radiants that demand even the dopiest driver's attention.
Best overall: Exposure Boost-R with ReAKT and Peloton
Best money-no-object: Garmin Varia RTL515
Best budget rear light: ETC R65 65 Lumen USB Rear Light
Best rear light for brightness: Cateye Viz 450 Rear Light
Best affordable rear light: Gemini Juno 100 rear light
Best for extra visibility: Brightside Bright, Amber and Sideways
Best combined helmet light: Exposure Link DayBright MK2
Best rear light with a camera: Techalogic CR-1 Rear Light with HD Wide Angle Camera
Best for commuting: Kryptonite Incite XR USB Rear
A more affordable rear smart light: Bryton Gardia R300L Rear View Bike Radar Tail Light
Best super bright rear light: Lezyne Zecto Drive Max 250
Lightest road.cc-recommended rear light: Knog Plus Rear Light, Black
Bets mid-priced rear light: Giant Recon TL 200 rear light
A rear light is a legal requirement when cycling at night, and using one that's brighter than the legal minimum seems like a sensible way of helping drivers see you — or at least defanging 'but I didn't see them' excuses. The best bike rear lights have long run-times, can be seen from a good distance, and are sufficiently tough and waterproof to fend off day-to-day abuse.
Cycling rear lights universally use one or more red light-emitting diodes (LEDs) to generate their light. LEDs are very efficient, putting out lots of light for modest electrical power, which makes them cheap to run but effective at boosting visibility. Most rear bike lights are now rechargeable, taking power from a USB source like a standalone charger or your office computer. Battery-powered lights are still available and have their adherents who appreciate being able to revive a dead light at any filling station or corner shop.
A flashing red light says 'bike' to most drivers; we recommend using a constant light as well so your position can be easily followed. It can be hard to track the position of a flasher on an otherwise unlit minor road. Rear bike lights are increasingly intended as day-time safety lights too, with super-bright flash or pulse modes designed to be impossible for drivers to ignore. They can be very annoying to other riders though; please use them only when necessary.
If you want to see our top picks of back, front and combined lights all in one place, you can also check out our overall guide to the best bike lights. Just looking for a front beam? Head on over to our guide to the best front bike lights instead.