Best Water Butts 2026 (UK): Which Size and Style Should You Buy?

Buying Guides › Rainwater Harvesting

Best Water Butts 2026 (UK): Which Size and Style Should You Buy?

By Jim Fellows, Garden Machinery Specialist · Updated July 2026 · 12 min read

Another dry spring, another round of hosepipe restrictions across parts of England - and water bills that keep climbing. A water butt remains the cheapest, simplest piece of kit you can add to a garden: it pays for itself, your plants prefer soft rainwater to treated tap water, and it takes an afternoon to install.

For this guide we've focused on the range at Water Butts Direct, one of the UK's largest specialist suppliers. They stock everything from £35 slimline butts to 1,200-litre tanks, carry the major UK-made brands (Straight, Harcostar, Blackwall, Strata), and sell the award-winning Gutter Mate diverter that we recommend further down. You can browse all of our rainwater harvesting coverage on our water butts hub.

Here's how the range breaks down - and which one is right for your garden.

Best Water Butts 2026: At a Glance

*Prices checked at waterbuttsdirect.co.uk, July 2026. Subject to change.

1. Harcostar 227L Water Butt Kit - Best Overall

£70.00 with stand, tap and diverter included

If you want one recommendation and no homework, this is it. The Harcostar 227L (that's a classic 50-gallon barrel) has been a fixture of British gardens for decades, and this kit version is the sensible way to buy it: the stand, tap and rain diverter are all in the box, so there's nothing else to order and nothing to bodge together from spare parts.

Harcostar is part of Straight Ltd, one of the UK's largest water butt manufacturers, and the barrel is blow-moulded here in Britain from recycled high-density polyethylene. The result is a light but genuinely tough container backed by a 5-year guarantee on manufacturing defects. The child-safe lockable lid is a small detail that matters enormously if you have young children or curious pets, it's fitted as standard.

The included Harcostar Rain Trap diverter is impressively universal: it fits 63mm, 68mm, 80mm and 100mm round downpipes plus 61mm and 65mm square profiles, and comes with a 0.5m flexible hose so the butt doesn't have to sit directly under the downpipe. The only pipes it won't work with are cast iron.

At 96cm tall and 60cm in diameter, it needs a proper corner rather than a narrow passage, that's really the only caveat. If your space is a strip down the side of the house, look at the slimline options below instead.

2. Strata 100L Slimline Space Saver - Best Budget & Small Spaces

From £34.99 (butt, tap & lid) · kit with stand and diverter also available

The cheapest sensible entry point into rainwater harvesting, and arguably the cleverest design in the whole range. The Strata 100L Space Saver is square rather than round, which means it sits flat against a wall or fence and slots into gaps a barrel could never occupy - down the side of a shed, on a decked corner, beside the back door.

Despite the price, the fundamentals are right: it's made in the UK from 100% recycled plastic to strict quality control standards, carries a 5-year guarantee, and comes with tap and lid. For a few pounds more, the kit version adds a multi-piece stand and a diverter that fits standard 68mm round and 65mm square downpipes - which covers the vast majority of UK homes.

One hundred litres won't see a big garden through a dry fortnight, but for a courtyard, balcony downpipe, greenhouse or shed roof it's exactly the right tool. Many buyers start with one of these and add a second once they realise how quickly it fills.

3. Garden Lake 400L Rainwater Harvesting Kit - Best Value Per Litre

£119.99 for 2 × 200L butts with stands, diverter and linking kit

Do the arithmetic and this kit is hard to argue with: 400 litres of storage for £119.99 works out at roughly 30p per litre - comfortably the best value in the range. You get two 200L Garden Lake butts, two stands, a diverter and the linking kit that joins the pair together, so when the first butt fills, the overflow tops up the second automatically.

This is the setup we'd point at anyone with a vegetable patch, an allotment-scale plot, or simply a lot of pots. Four hundred litres is enough to keep a serious garden going through the sort of dry June we've had two years running, and because it's two separate containers you can position them side by side or stagger them along a wall.

Worth knowing: a single 200L Garden Lake butt is available from £49 if you'd rather start smaller and link a second one later - the linking approach is modular by design.

4. Strata 250L Black Slimline - Best Slimline Capacity

From £67.99 with tap and lid

The problem with most slimline butts is that "slim" usually means "small". The Strata 250L is the exception: a square, space-saving profile in matte coal-black plastic that still holds a full 250 litres - more than the classic Harcostar barrel - while remaining easy to position against a wall or on a decked area.

The matte black finish is genuinely smart, and it's the pick we'd suggest for modern gardens where a dark green barrel would look agricultural. It ships with tap and lid; the stand and diverter are optional extras, so budget for those. One quirk to note: the diverter inlet points at the top are templated but not pre-drilled, so you'll need a drill and ten minutes of care when fitting a diverter or linking kit.

5. 350L Magnum Rain Barrel - Best for Large Gardens

From £130.00 · free delivery at time of writing

When 227 litres isn't enough and you'd rather not manage two linked butts, the Magnum is the single-container answer. At 350 litres it's the largest conventional barrel in the Harcostar family - beyond this you're into the Polytank territory of 1,200-litre tanks, which is a different proposition (and a different budget) altogether.

Like its smaller siblings it's UK made from recycled HDPE with the child-safe lid fitted, and it takes the same universal Rain Trap diverter and accessories. A butt this size holds roughly a third of a tonne of water when full, so get the position right first time - level, firm ground, ideally paving slabs - because you won't be nudging it once it starts filling.

6. The Decorative Options: Rattan Effect & Planter Butts

150L Rattan Wicker Effect Polybutt from £100 · 180L Garden Planter Water Butt £247.99

Not everyone wants their rainwater storage to look like rainwater storage, and this is where the range gets interesting. The 150L Rattan Wicker Effect Polybutt (green or black, from £100) does a convincing impression of woven garden furniture, and there are woodgrain-effect versions from £115 in black, green and oak brown if you'd rather it read as a timber barrel.

The premium play is the 180L Garden Planter Water Butt at £247.99 - a butt with an integrated planting bowl on top, available in an unusually broad palette (green, black, millstone, purple, pink, orange, blue stone). Plant it up with trailing bedding and visitors simply won't clock that it's a water store. It's the most expensive per litre here by some distance, but it's solving a different problem: it earns a place on the patio itself, right where watering happens.

Water Butt Buying Guide: What Actually Matters

What size water butt do I need?

As a rule of thumb: 100L suits a courtyard, balcony or greenhouse; 200–250L suits a typical family garden with borders and pots; 350L+ (or a linked pair) suits vegetable growers and larger plots. Remember that a modest UK roof sheds thousands of litres a year - the butt fills far faster than most people expect, so if in doubt, size up or choose a model that can be linked later.

Check your downpipe before you order

Measure your downpipe's diameter and note whether it's round or square. Most UK homes have 68mm round or 65mm square plastic pipes, which every diverter here accepts. The Harcostar Rain Trap stretches the compatibility further (63–100mm round). The recurring exception across the whole range: cast iron downpipes aren't supported - if you have a period property with original ironwork, speak to the supplier before ordering.

Always use a stand

A tap at ankle height is useless - you need room to fit a watering can underneath. Kits that include the stand (the Harcostar 227L kit, the Garden Lake 400L kit, the Space Saver kit) save you buying one separately, which is why we've favoured them throughout this guide.

How do I keep water butt water fresh?

Stored rainwater goes green and smelly if you let light and debris in. Three cheap fixes: keep the lid on (it also keeps children, pets and mosquitoes out), fit a filtering diverter such as the Gutter Mate, and drop in a treatment - either a natural water butt treatment with UV blocker, a microbial disc, or a FreshaTank copper/silver disc. Give the butt an annual rinse-out in winter when it's cheap to empty.

Is rainwater better for plants than tap water?

Yes - rainwater is naturally soft and free of the chlorine and fluoride in tap water, which is why gardeners have always preferred it, particularly for ericaceous (acid-loving) plants like rhododendrons, camellias and blueberries. It's also the obvious choice for topping up ponds.

Frequently Asked Questions

Can I use a water butt during a hosepipe ban?

Yes. Hosepipe bans restrict the use of mains water through a hose - water collected in a water butt is yours to use freely with a watering can, and most restrictions also permit hand-watering from stored rainwater. Always check your local water company's specific rules, but a full butt is exactly what gets gardens through a ban.

How long can rainwater be stored in a water butt?

Indefinitely for garden use, provided the lid stays on and debris is filtered out. Water that's kept dark, covered and reasonably clean won't "go off" for irrigation purposes - problems only arise when light, leaves and organic matter get in and encourage algae. A filtering diverter and an annual rinse solve this.

Is water butt water safe to drink?

No. Stored rainwater is untreated and is for garden and outdoor use only - watering plants, topping up ponds, washing tools and cars. It should never be used for drinking, cooking or filling paddling pools.

Do I need planning permission for a water butt?

No - standard domestic water butts, including large 350L barrels and linked twin setups, don't require planning permission in the UK. They're a plug-in addition to your existing downpipe.

Garden Review is reader-supported. This guide references products sold by Water Butts Direct; prices were checked in July 2026 and may have changed. If this page contains affiliate links, we may earn a commission at no extra cost to you. This does not influence our recommendations.