What a single camera misses
A front only dash cam records what happens in front of your windscreen. Useful as that is, it leaves gaps. The disputes that UK drivers actually argue about tend to happen at junctions, roundabouts, and car parks, and a lot of that action takes place behind you.
A driver rear ends you and claims you reversed into them. Another cuts across you from a side road with no warning. A hit and run happens while your car is parked overnight. With a front camera alone, the story is half told in every one of those scenarios. Add a second camera facing out of the rear window, and the two recordings together give you the full picture.
The insurance argument for front and rear
Insurers accept dash cam footage as evidence, and plenty of them now knock money off premiums for having one fitted. A rear camera strengthens your position in a claim because it shows the incident from two angles.
In a rear end collision, the driver behind is usually at fault, but that is not always how it plays out. If the other party claims you braked suddenly or reversed into them, footage from the rear camera settles the argument. Without it you are left relying on witness accounts and whoever tells the more convincing story.
Worth knowing: footage can also support claims for damage caused by careless driving. See how dash cams affect car insurance →
Parking mode with rear coverage
Parking mode keeps the camera recording while the car is switched off, triggered by motion or impact. If your car lives on the street or in a shared car park, the rear camera is often the one that catches the culprit. Most parking bumps happen to the back of the car, because that is the side other drivers reverse into.
A dual channel camera with parking mode covers both ends. Someone clips your bumper and drives off, and the rear camera has their number plate. A shopping trolley rolls into your door, and the front camera catches it. For anyone parking on the street, that is the difference between having evidence and having nothing.
What to look for in a dual channel dash cam
Dual channel systems vary more than the price suggests. The rear camera on cheaper models records at lower resolution, and footage that is too soft to read a number plate is not worth much. Look for a rear camera that records at least 1080p, ideally with a wide angle lens that covers both lanes behind you.
It is worth thinking about how the two cameras connect. Some rear cameras plug into the main unit with a cable, while others pair wirelessly. Wired connections are generally more reliable and keep both cameras recording in sync. Also check how the rear camera is powered. Some systems only run the rear camera while driving, while others keep it active in parking mode.
If night driving is a regular part of your routine, look closely at the night performance of both cameras. A front camera with strong night vision but a weak rear camera still leaves you exposed after dark.
Installation is easier than you think
Fitting the rear camera is the part that puts most people off, but it is a manageable DIY job. The camera mounts to the rear window and the cable runs along the headliner and door pillars, tucked out of sight. Most kits include a trim tool to help you hide the cable without damaging anything.
If that sounds like too much, plenty of local fitters will install a dual channel system in under an hour. See our dash cam installation guide → for the step by step.
Should you upgrade?
If you already run a front only camera and you have had it for a while, upgrading to dual channel is one of the most useful things you can do. The extra camera costs very little compared with the price of a disputed claim. If you are buying your first dash cam, starting with front and rear means you never have to wonder what was happening behind you.
Browse the front and rear dash cam reviews → to compare the models we have tested, and pick the one that fits your car and your budget.
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