LAST UPDATED: December 25, 2020

The Best Rear Bike Lights (Review & Buying Guide) in 2021

Best Choice Ascher LED Bike Tail Light Ascher LED Bike Tail Light
Best Value Stupidbright SBR-1 Rear Bike Light Stupidbright SBR-1 Rear Bike Light
Premium Pick Garmin Varia RTL510 Tail Light Garmin Varia RTL510 Tail Light

You can’t do anything about the dark nights, foggy mornings with low visibility, or careless and sleepy drivers on the road. You still have to power through and cycle to or from work despite these conditions. One of your best lines of defense against the perils on the road is installing headlights and rear lights on your bike to help illuminate your cycling path and make you more visible on the road. 

As the name suggests, rear bike lights (also known as tail lights) are attached to the back of your bike. You can also attach these lights anywhere on the wheel frame, on your cycling gear, or on your backpack. If you are in the market for a great set of rear bike lights, then this is a great place to start.

Each of these lights is fitted with five LED chips and features four light modes: full, half-bright, slow flash, and fast flash. To prevent rain damage, the lights are IPX4-rated for water resistance so you can stay visible even when riding in the rain. A rechargeable 330mAH lithium battery powers the lights. The lights can last for a maximum of 11 hours if used on slow flashing mode. They can be mounted on the seat post either vertically or horizontally, and you can detach them without removing the mounting strap. You also get two USB charging cables for each light.

One drawback to these rear bike lights is that they are not as bright as higher-priced rechargeable lights. Also, they don’t hold a charge for long when at the highest mode setting.

Key Features
  • Five LED chips
  • Four light modes
  • USB rechargeable
  • Up to 11 hours of battery life
Specification
  • Brand Ascher
  • Model N/A
  • Weight 4.48 ounces
PROS

Great bargain

Easy to install on any bike

Resistant to inclement weather

Small and compact

CONS

Not as bright as higher-priced rechargeable lights

Doesn't hold a charge for long at the highest setting

These rear bike lights produce a wide 180-degree beam that’s visible from the back and sides. By simply pushing a soft click-button, you can switch between three light modes: solid, fast-strobe, and slow strobe. It features high-intensity LED bulbs that are housed in a water- and shock-resistant aluminum alloy casing. The construction also includes a rubber gasket that helps to keep water out of the battery compartment. The lights come with a versatile rubber strap that can attach to your backpack, bike frame, or your helmet. You have to budget for disposable batteries in the long run, but the manufacturer starts you off with two long-lasting CR2032 lithium batteries.

Some downsides of this rear bike light are that it doesn’t have a rechargeable battery, so it’s not as bright as rechargeable lights. Also, the light doesn’t fit securely on thinner seat frames.

Key Features
  • 180-degree beam angle
  • Aluminum construction
  • Water- and shock-resistant
  • 50-hour battery life
Specification
  • Brand Stupidbright
  • Model SBR-1
  • Weight 0.09 pounds
PROS

Comes with two tail lights

Durable construction

Comes with a non-slip rubber strap mount

Batteries included

CONS

Non-rechargeable battery

Doesn’t fit securely on thin seat frames

Not as bright as rechargeable lights

This rear bike light emits a 220-degree beam within a range of 459 feet that’s strong enough to be visible in the daytime. It’s also a smart gadget and has a sensor that will give you audio and visual alerts whenever a vehicle is approaching at high speeds within its range to provide you with enough time to react. The lights feature three light modes: flash, solid, and night flash mode. It’s powered by a single lithium-polymer battery that can last for a maximum of 15 hours in flash mode. The unit mounts vertically on the saddle post and can be mounted on racing, touring, commuter, and off-road bicycles.

A few things to note about these lights is that they can only be mounted on the seat post and nowhere else on the bike, and the audio alert may be inaudible. Also, it’s a super expensive option.

Key Features
  • 220-degree beam angle
  • 459 feet (153 yards) sensor range
  • Up to 15 hours of battery life
  • Three lighting modes
Specification
  • Brand Garmin
  • Model 010-01980-00
  • Weight 0.51 pounds
PROS

Compatible with other Garmin devices

Can be used as a standalone light

Long battery life

Fits securely on the seat post

CONS

Expensive

Can only be mounted on a seat post

The audio alert may be inaudible

This compact tail light from Cygolite is a two-watt, red, LED bulb that emits 150 lumens of light. The bulb is fitted in a durable and water-resistant plastic housing. With five lighting modes, you can have the lights on in both daytime and at night. They include steady, zoom, day lightning flash, triple flash, and random flash. It runs on a rechargeable battery, and depending on the mode you choose, the battery can last for 4.5 to 500 hours. You can mount it on a backpack, wheel frame, or the seat post.

The battery may drain even when the light isn’t in use and may die if you let it drain completely, but Cygolite includes a battery life indicator that lets you know when the battery is almost depleted. Also, the mode selection button can be somewhat difficult to press.

Key Features
  • Two-watt LED light
  • USB rechargeable battery
  • Water-resistant construction
  • 4.5 to 500-hour runtime
Specification
  • Brand Cygolite
  • Model N/A
  • Weight 0.2 pounds
PROS

Compact and lightweight design

Comes with a USB charging cable

Comes with five different lighting modes

Long battery life on the lowest mode

CONS

Can’t hold a charge when it’s not in use

Mode selection button can be somewhat difficult to press

Battery may die if you let it drain completely

The light comes with two 0.5-watt LED bulbs that light up in red with three different lighting modes: pulse, flash, and steady mode. A rear-mounted switch button helps to adjust the mode. It’s powered with two AAA batteries, and though they are disposable, they offer a long 50-hour runtime on flash or pulse mode and 15 hours on steady mode. The bulbs are housed in a weatherproof, plastic housing that resists fogging in rainy or humid conditions. It comes with an adjustable mounting bracket, and the manufacturer also includes a backpack clip if you don’t want to have it on your bicycle.

However, some downsides to this rear bike light are that the horizontal mounting bracket is sold separately. Also, customers report that the light has low visibility during the day.

Key Features
  • 0.5-watt, LED bulb included
  • 50-hour maximum run time
  • Three lighting modes
Specification
  • Brand Portland Design Works
  • Model 410
  • Weight 1.59 ounces
PROS

Extra backpack clip included

Easy installation

Emits a bright light

Weather-resistant design

CONS

Horizontal mounting bracket sold separately

Non-rechargeable battery

Low visibility at day time

This light not only keeps you safe at night but also during the daytime thanks to NiteRider’s Daylight Visible Flash (DVF). It features four light modes, including high, low, pulse flash, and fast flash mode. The light is powered with a USB-rechargeable lithium polymer battery that can run for a maximum of 15.5 hours and a minimum of 4.5 hours, depending on the light mode. A low-battery indicator will flash blue when the battery level is below 20 percent, giving you enough time to cycle back home and charge it. Additionally, it’s made of plastic material that’s dust resistant and has an IPX4 rating for water resistance.

There are some issues with this light’s battery: the battery has a long charging time and takes two hours to charge to full capacity. Also, the battery has a short lifespan on the highest flash mode.

Key Features
  • Daylight Visible Flash
  • Two steady and two flash modes
  • USB rechargeable battery
Specification
  • Brand NiteRider
  • Model 5084
  • Weight 0.18 pounds
PROS

Increases rider safety even at daytime

Long-lasting battery

Includes a low-battery indicator

Covered with a limited lifetime warranty by NiteRider

CONS

Bulky body

Long charging time

Short battery lifespan on high mode

Best Rear Bike Lights Buying Guide & FAQ

If you already have a bike bell, light reflector, and a helmet, then the next logical step to improving your safety on the road is to add rear lights to your bike. Since you can’t always look back as you cycle, rear lights come in handy for keeping you secure from the rear; motorists can spot you even if you can’t see them.

However, how do you find a rear light that fits your budget, suits your riding style, and is adaptable to your cycling environment? You only need to go into the market armed with all the information you can get on rear bike lights. This involves knowing how to identify a good or subpar product, and our buying guide will help you with this. 

The Benefits of Owning a Rear Bike Light

Most bikes come with a red light reflector that’s positioned at the back of the bicycle. This meets basic legal requirements, but there are times when motorists cannot see this red reflector, which could lead to an accident. For this reason, you need to upgrade to an active rear light that either runs on batteries or charges with a USB to help to draw attention to your bicycle.

Rear lights are not only useful at night, but in other low light conditions, including rainy days, foggy mornings, or when cycling in dimly lit alleys. You can also leave them on during the daytime for enhanced safety.

  • It helps you cycle more safely in the dark. 
  • It can be attached almost anywhere on your clothing, backpack, or bike. 
  • It installs easily with no extra tools or equipment. 
  • It can upgrade the look of your bike. 
  • You can install more than one rear light to be more visible. 

Popular Types of Rear Bike Lights

the best rear bike lights to install
Rear bike lights help make you more visible on the road

All bike lights typically function the same way—that is, they illuminate light within a specific range to make the cyclist more visible. However, some run on rechargeable batteries, whereas others run on disposable batteries.

USB Rechargeable 

If you only use your bike for short trips or commutes, then rear lights with a USB-rechargeable battery will work for you. The light is typically fitted with a lithium-ion or lithium-ion polymer battery that’s charged via a USB connection. These types of batteries will last for at least four hours.

They come with different lighting modes, and you can switch to the lowest setting if you want to preserve the battery. You can get about 11 hours of continuous use with most of these rechargeable lights on the lowest setting. Some advanced options come with battery life indicators so you can tell when the battery is almost depleted. The main drawback of this option is that you have to replace the lights if the charging system is faulty or if the built-in battery dies. 

Non-Rechargeable

Lights that use disposable batteries are usually the least expensive on the market. This is because they have a simple design with a metal or plastic housing and a battery compartment. The disposable batteries can last for up to 50 hours before you have to replace them. Therefore, they are better for longer journeys where you don’t have time to stop and recharge the battery.

However, this option isn’t as eco-friendly since most disposable batteries contain harmful chemicals, and they have to be properly disposed of. 

What to Look for When Buying Rear Bike Lights

We prioritized bright rear lights that have various light modes. You want the allowance to switch between a steady and a flash mode whenever you need to. The beam angle is equally important, especially if the lights are being used on a mountain bike. We chose lights with a wide beam angle of about 180 degrees or more to be visible from the sides. 

Any light that’s mounted on your bike should have a long-lasting battery that can last you through several trips or at least your daily commute. This is why we included lights with long-lasting, rechargeable or disposable batteries.

We also prioritized lights that are easy to install. This includes minimal designs with a lightweight mounting bracket that quickly attaches to your seat post. The mounting system should also have rubber straps that can remain firm on the seat even when you’re riding on rugged terrain. 

The Most Important Features of Rear Bike Lights

rear bike lights installed on a bike
Rear bike lights are a must-have

The market is flooded with a variety of rear bike lights that come in different shapes and designs. The following features will help you narrow down your options so you can end up with the best rear lights for your bike. 

Lumens

The amount of light emitted by a bulb is measured in lumens, or simply put, it’s the brightness level of your rear light. You want a rear bike light that’s bright enough for the driver behind you to see you but not too bright that it blinds them. A lumen count of about 50 to 200 is ideal for a rear light.

You should also consider where you will be cycling so you can determine the appropriate brightness level. For example, if you only use your bike to commute, you can choose a bulb with a smaller lumen count. However, if you use your bike for mostly off-roading on rugged terrain, then you can choose a light with a higher lumens count so it can make you more visible in the less-traveled route. 

Light Settings 

The best cycling lights have multiple light settings or modes to choose from, so you can adjust the light to suit the cycling environment or the time of day. The most basic important function is a steady mode, where the light doesn’t flash or pulsate. It can be used for night riding in a less crowded city.

Pulse, blinking, or flashing lights are warning lights that are best used in crowded cities so you can draw the attention of motorists to your bicycle. These modes also help save on battery power so that you can ride for longer with the lights on. Also, ensure that the design allows you to switch between the modes easily. 

Design 

Always choose lights with a compact and lightweight design, so it doesn’t take up too much space on your saddle post. You don’t want a heavy unit that slides down the frame whenever you ride on rugged terrain. Also, ensure the design allows for optimal light output. The bulb casing should enable the bulbs to provide a wide beam with no obstructions. 

Besides that, ensure that the unit has a weather-resistant construction to keep on working through the rain or snow. It should also have a solid build that resists damage from road debris.

Best Rear Bike Lights FAQs:

When choosing a rear bike light, it’s evident that you need one that provides decent lighting, whether at night or daytime. This helps to ensure your safety on the road at all times. If you are looking for further clarification on rear lights, read some of the answers we’ve provided to some frequently asked questions.

Q. How many lumens do I need for a rear bike light?

The lumen count on rear bike lights is typically around 50 to 200 lumens. You can choose a lumen count on the lower side for street riding, so you don’t blind other road users. However, if you have a mountain bike and mostly use it for trail riding, then you need a brighter light that can go beyond 200 lumens. 

Q. What is the brightest rear bike light?

The Garmin Varia RTL510 Tail Light is one of the brightest lights out there and can illuminate a distance of about 153 yards. It’s bright and powerful enough to be used as a standalone rear light. 

Q. What is the best bike light for night riding?

Any of the lights featured in our review will provide decent illumination for night riding. 

Our Top Pick

The Ascher LED Bike Tail Light tops our list thanks to its rechargeable lithium battery, four light modes, and an IPX4 rating for water resistance. We love that this light can be mounted to the seat post both vertically and horizontally and that it lasts for a maximum of 11 hours. 

Final Thoughts

If the Ascher LED Bike Tail Light is out of your budget, then you can opt for the Stupidbright SBR-1 Rear Bike Lights. You get a pair of bright lights at an affordable price, and they are easy to install. They are great for long trips on the trail since they come with long-lasting batteries that can last for up to 50 hours.

Sources:

  1. Bicycle Lighting – Wikipedia