Best Waterproof Backpacks for Cycling: Full Bags vs Covers

Shopping for the best waterproof backpacks for cycling usually ends one of two ways. You either spend £80 to £200 on a dedicated waterproof rucksack, or you spend a tenner on a cover that goes over the bag you already own. The received wisdom says buy the proper bag. The maths doesn't always agree, and for a lot of UK commuters the cheaper route keeps your kit just as dry.

Here's an honest look at both, including where expensive "waterproof" bags actually let water in, so you can spend your money where it counts.

The two ways to keep your kit dry

A dedicated waterproof cycling backpack is built to shed water: welded or taped seams, a roll top or storm zips and a laptop sleeve inside. A waterproof cover is a lightweight skin you stretch over a normal rucksack when the rain starts, then pack away when it stops.

Both work. They just suit different riders, and the gap in price is bigger than the gap in dryness. Let's take each in turn.

Option one: a dedicated waterproof backpack

If you commute five days a week in all weathers with a laptop on your back, a purpose built bag makes sense. There's no faff in the rain: you close it once and everything's sealed.

The bags that come up again and again in UK reviews sit in a few tiers:

• Roll top classics: the Ortlieb Vario and Rains Rolltop seal by rolling the top down three or four times. No zip means no zip to leak.
• Commuter workhorses: the CamelBak H.A.W.G. Commute (around £160) and Chrome Barrage use tough coated fabric and storm flaps over the zips.
• Water resistant all rounders: bags like the Osprey Metron shrug off a shower and often ship with a separate rain cover, which tells you something about how far the bag alone will get you.

What to look for is short: a roll top or storm zip closure, taped or welded seams, a padded laptop sleeve and some reflective detail for the road. Capacity of 20 to 30 litres covers a laptop, a change of clothes and shoes for most commutes. You rarely need more.

The catch is the price. A genuinely waterproof bag with taped seams starts around £80 and climbs past £150 fast. You're also committed to that one bag, whether or not you like carrying it.

Option two: a cover over the bag you already own

A hi vis waterproof backpack cover takes a different approach. Instead of buying a new bag, you keep the comfortable one you own and pull a waterproof skin over it when the sky turns. Covers cost roughly £5 to £20, pack down to the size of your fist and weigh almost nothing.

The commuter's trick is to layer up cheaply. A normal rucksack you already like, a £10 to £15 reflective backpack cover over the outside and a small dry bag inside for the laptop and phone. That's genuine protection for around £25 to £40 all in, against £150 for a single waterproof bag. We break down that comparison further in backpack cover vs waterproof bag.

There's a second win that pure waterproof bags miss. Most dedicated bags are black. A bright yellow reflective cover turns the biggest surface facing following drivers into a hi vis panel, which matters far more on a dark, wet commute than a few grams of fabric. On UK roads, being seen is the harder problem to solve.

The honest downside is the faff. When the rain starts you have to stop, pull the cover out and stretch it on, which takes 15 to 30 seconds. For an occasional or part time commuter that's a fair trade. For someone riding hard through winter every day, the no stop convenience of a sealed bag wins. Our guide to the best waterproof backpack covers for cycling covers fit and sizing if you go this way.

Where "waterproof" backpacks actually leak

This is the part the product pages skip. A bag labelled waterproof isn't a sealed box, and water finds the weak points.

• Zips: a standard zip is a line of holes. Only taped or storm flapped zips hold water back, and cheaper "waterproof" bags often skimp here.
• Seams: stitched seams leak unless they're taped or welded. This is what separates a £40 bag from a £120 one.
• Strap anchor points: where the shoulder straps are stitched to the body is a classic slow leak on heavy rides.
• The back panel: pressed against your back and under load, it's the panel most likely to wet through in prolonged rain, whichever option you choose.

This is why roll top bags have a following. With no zip and a rolled closure, there's simply less for water to exploit, as long as you roll it down properly. Rushed, single fold closures are the most common reason a "waterproof" roll top still leaks.

The sweaty back nobody solves

Ask commuters what they actually complain about and it's rarely rain getting in. It's the damp patch on their back, and that's condensation, not leakage. Your back heats the panel pressed against it and moisture has nowhere to go.

No backpack fully fixes this, waterproof or not. A ventilated back panel helps, a technical base layer helps more, and on the wettest days many commuters accept a change of shirt at the other end. If a dry back matters that much to you, panniers are worth a look, because they move the load and the sweat onto the bike instead of your spine.

So which should you choose?

Match the kit to how often you actually ride in the wet.

• Two or three days a week, or fair weather with the odd soaking: a reflective waterproof cover over your existing bag, plus a dry bag for the laptop. Cheap, visible and there's nothing to learn.
• Five days a week, all winter, laptop every day: a dedicated roll top waterproof backpack earns its price through sheer convenience. Prioritise taped seams, a roll top closure and a proper laptop sleeve, and don't overpay for litres you won't fill.

Neither is wrong. A £15 hi vis cover on a bag you're happy to wear beats a £150 waterproof bag that digs into your shoulders, and it makes you easier to see in the dark. Spend on the problem you've actually got. If that problem is an occasional soaking, you don't need to spend much at all. For more on keeping the contents dry day to day, see how to keep your backpack dry while cycling to work.

Frequently asked questions

Are waterproof cycling backpacks actually waterproof?

The good ones are, up to a point. Roll top bags with welded seams keep water out reliably, but cheaper bags labelled waterproof often leak at the zips, seams and strap anchors. Check for taped seams and a roll top or storm flapped zip rather than trusting the word on the label.

Is a waterproof cover as good as a proper waterproof bag?

For most commuters, yes. A cover plus a dry bag inside for electronics protects your kit for a fraction of the cost, and a hi vis cover adds visibility a plain black bag can't. The trade off is stopping to fit it when the rain starts, which suits part time commuters more than daily ones.

How do I stop my back getting sweaty with a backpack?

You largely can't, because the damp is condensation from your body heat rather than rain. A ventilated back panel and a technical base layer help. If it really bothers you, panniers shift the load off your back and onto the bike.

What size backpack do I need for commuting?

Around 20 to 30 litres suits most commutes with a laptop, a change of clothes and shoes. Go smaller if you travel light. Bigger bags tempt you to overpack and sit awkwardly when half empty.

Backpack or panniers for a rainy commute?

Panniers keep weight and sweat off your back and carry heavy loads more comfortably, but they need a rack and are less flexible. A backpack is quicker to grab and go. Plenty of commuters keep both and choose by the day.