The best bike rear light is more than just a red LED blinking away at the rear of your bicycle; it also provides an extra layer of security to your rides, no matter the light conditions. Some models even have built-in cameras that connect to your smartphone and alert you of potentially dangerous traffic situations as they unfold behind you.
According to research, the "majority of casualties occur during daylight, but there is still a significant minority that occurs after dark." Drivers are often sleepy, and visibility is often poor in the mornings and early evenings, so it is highly recommended that you add a bike light to your bicycle before you kick off from the curb.
If you're interested in cycling gear, check out T3's best electric bike and best road bike guides. These days, most electric bikes come with built-in lights, but road bike users can also benefit from browsing our best front bike light guide.
Our current favourite bike rear light is the Bontrager Flare RT, which offers excellent overall performance with its 90-lumen output, compact size, and impressive visibility range. For those needing a built-in camera, the Garmin Varia RCT715 is the best choice, featuring rear radar and a 1080p dash cam. If you're looking for a light that's ideal for daytime use, the Lezyne Strip Drive Pro 400+ stands out with its 400-lumen output and long battery life.
Best bike rear lights to buy right now
Why you can trust T3
Best overall
The Bontrager Flare RT is now 30% more powerful at 90 lumens and 36% smaller. It offers excellent visibility up to 2km, multiple modes, battery-saver, and smart connectivity with Garmin devices.
Best for built-in cam
Garmin's rear safety device includes rear radar and a 1080p dash cam. It detects vehicles up to 140m away, pairs with Garmin Edge for warnings, and saves incident footage, offering six hours of battery life.
Best for daytime use
The Lezyne Strip Drive Pro 400+ boasts longer battery life, brighter 400-lumen output, compact shape, faster charging, and 270° visibility. It's waterproof (IPX7) and easily mounts on most bikes.
Best overall
1. Bontrager Flare RT2
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The Bontrager Flare RT was already one of our favourite lights, but this version steps things up a notch. It’s 30 per cent more powerful, with the maximum output now amped up to 90 lumens, and 36 per cent smaller, so while the light may pack a mean punch, it takes up barely any space on your bike.
Bontrager was among the first brands to pioneer daytime bike lights, and the Flare RT has a specifically designed focus and flash pattern for daytime use. That, combined with the raw power of the light, apparently means it’s visible up to 2km away on the most powerful setting. Otherwise, you also have 45-lumen and five-lumen flash modes to choose from, as well as 25-lumen and five-lumen steady-state options.
The Flare RT may have one simple goal at its heart – to keep you seen on the road – but it’s a smart little light, too. The battery-saver mode provides 30 minutes of additional runtime when the juice reaches 5%, while Ant+ and Bluetooth Smart connectivity means you can pair the light with your Garmin computer. For example, you can program the Flare RT to automatically turn on whenever your computer is powered up, or you can keep an eye on the battery life using one of your Garmin’s data screens.
Best with built-in cam
2. Garmin Varia RCT715
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Garmin has crammed a lot into this diminutive safety device, including rear radar and a dash cam for the back of your bike.
Granted, it’s a ridiculously expensive rear light, but it is one of the only lamps on the market that has your back in the case of close calls or accidents.
Based on the RTL515, the rear radar detects approaching vehicles from up to 140 metres away.
Once detected, it can pair to one of Garmin’s Edge head units (as well as some others) to offer a visual and audible warning of approaching vehicles, as well as their approach speed.
The integrated camera records what’s behind you at up to 1080p/30 fps and automatically saves the incident if it detects and accident.
Use Garmin’s Varia app to access footage, while a battery life of up to six hours should be enough for even those longer rides.
Best for daytime
3. Lezyne Strip Drive Pro 400+
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The Lezyne Strip Drive Pro range has been in existence for some time now and the 400+ essentially builds upon everything that has historically made this series great.
A longer battery run time, brighter output, more compact shape and faster charging are just a few headlines, although we appreciate the fact Lezyne designers have managed to increase the visibility range to a whopping 270° visibility range.
For us, this has been a regular fixture on the back of our test bikes, as the long battery life and super bright 400 lumen output means it increases visibility in pure daylight, as well as during those low light evening rides.
It is contracted and tested to IPX7 waterproofing standards, which means it can take a battering from the elements, while the simple rubber band mounting system ensures it will happily attach to most bikes - even those with fancy aero posts.
Best value rear camera
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The DVR80 pairs a brilliant rear light with a clear action camera that’s able to record in 1080p. The 80 lumens light is bright enough to be used during the day and at night, with claims by Tooo Cycling that it is visible one mile away.
The camera records clear footage in a variety of conditions. While it lacked the image stabilisation capabilities of the best GoPro, it's able to capture car license plates from upwards of five meters – important if you need video evidence after an accident or close pass.
The biggest failing of a rear light is often its durability in the face of the UK’s winter conditions. The DVR80’s IPX5 waterproofing passed our tests with flying colours during a month of use. It does come with a two-year warranty, though, if things don’t work out long-term.
Read our full Tooo Cycling DVR80 review.
Best for easy mounting
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The Thousand Traveler bike lights are a solid option providing exceptional visibility to others on the road. They’re a bit lacking in side visibility, and the headlight doesn’t offer much of a beam for spotting obstacles on the road, but this is a handy option for city riders who have well-lit streets and want extra-convenient lights that just help protect them from drivers.
Read our full Thousand Traveler Bike Light review.
Best budget
6. Moon Nebula
Specifications
Reasons to buy
Reasons to avoid
This neat little package arguably offers too much light for a rear light, which will only ever be a problem for those regularly riding in groups, but the Moon Nebula's super-bright LEDs are perfect for riders who want to alert fellow motorists to their presence.
A day flash mode gives a lower output to preserve battery levels but still affords good visibility, while the flashing night mode bangs out the maximum 180 lumens. The light's long, thin shape might not fit every mounting requirement, although plenty of mounting options are included in the box, so you should be able to find a space somewhere for the lights with a bit of searching.
How to choose and fit the best rear bicycle lights
The job of a front light is, at least in part, to illuminate the road ahead, as well as to attract the attention of motorists. On the other hand, rear bike lights are all about road safety – making yourself visible to other road users.
Needless to say, the consequences of a rear-end shunt can be severe, so it’s a wise idea to invest in a bright rear light to attract the attention of those around you. In fact, it’s the law. According to UK legislation (the Road Vehicles Lighting Regulations 1989, fact fans), it's illegal to cycle on a public road after dark without lights and reflectors. You’re unlikely to get pulled over if you eschew the latter, but lights are essential.
Rear cycle lights aren't only needed at night. In low light, fog or dappled shade, cyclists can be more difficult to spot on the road, especially if you like to look chic in all black kit. The same even goes for when it’s a beautiful day as a super-bright rear light can help keep you seen when riding into a dazzling low sun.
Due to the fact a rear light is only required to act as a safety beacon, rather than providing illumination to see by, it doesn’t have to be as powerful as a front light. Twenty lumens is a reasonable starting point, but the latest and greatest lights can pump out up to 300 lumens. If you plan on using your rear lamp during the day, the brighter the better, as it has to work harder to stand out - but be careful not to dazzle other road users at night. Also look out for lights with a range of settings, so you can tailor the brightness according to the riding conditions and battery life.
Even the most powerful rear lights tend to be a lot cheaper than the brightest front lamps, with the most expensive dipping below £150, and the average being way lower. It's possible to pick up a basic but powerful rear light for less than £20 so it’s difficult to justify going without.
Fitting rear lights should be simple, with most opting for a rubber strap or a simple plastic ratchet system that clamps around the seatpost. The rubber strap is our favoured system - it's so brilliantly simple, yet reliable (when done well) and means you should also be able to mount the light on an aerodynamic seatpost, as well as a conventional round design. Today’s designs are so slick that we look back on vintage lights with their elaborate metal and plastic clamping systems and wonder, "what were they thinking of?"
Most rear lights are now USB rechargeable, so while you may need to plug it in more often than you’d have to switch a set of regular batteries, it’s a doddle to keep the juice topped up. To be on the safe side, some riders even employ two rear lights, so that if one fails or runs out of charge/battery you're not unwittingly left without. Helmet-mounted lights are another great back-up option as they can be more visible than a seatpost light, which can be obscured by overhanging jackets (watch out for that!) or panniers.
Some rear lights are also designed to attach to backpacks or clothing, once again offering the chance to increase your illumination on the road, especially as they are mounted much higher than an under-seat light for improved visibility in heavy traffic.
So, in short, there's no excuse for not lighting up. Rear lights are more affordable and brighter than ever before, so you should be able to find something that fits your budget and riding style. Now let’s take a look at the best rear lights you can get for your money.
Even more info the subject of bike rear lights can be found here: how to choose the best front and rear bike lights. For those who need just one more article before they make a purchase.
FAQ
What is the brightest rear bike light?
How bright is too bright when it comes to bike rear lights? If your answer is 'nothing is too bright', consider the Lezyne Strip Drive Pro 400+, a red blinker with 11 different modes and a staggering 400-lumen light output.
You might think that 7 different modes for a bike rear light is a bit of an overkill and although we agree, but we also think it provides a lot of flexibility to riders to cheese the correct output for any riding session. You might want to have the max output mode on when it's foggy and you simply can't skip a training session, while other times, especially in broad daylight, a lower power setting might just be enough.
What is the best rear light right now?
For the sheer weight of features, it is difficult to top the Garmin Varia models, but we also love the Tooo Cycling DVR80 for its bright light and reliable camera. Of the more traditional lot, the super-bright and smart design of the rather more straightforward Bontrager Flare RT2 is a clear winner.
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Matt Kollat is a journalist and content creator who works for T3.com and its magazine counterpart as an Active Editor. His areas of expertise include wearables, drones, fitness equipment, nutrition and outdoor gear. He joined T3 in 2019. His byline appears in several publications, including Techradar and Fit&Well, and more. Matt also collaborated with other content creators (e.g. Garage Gym Reviews) and judged many awards, such as the European Specialist Sports Nutrition Alliance's ESSNawards. When he isn't working out, running or cycling, you'll find him roaming the countryside and trying out new podcasting and content creation equipment.