Insect Repellent Coils UK 2026: The Best Options for Camping, Gardens and Festivals

A British summer evening outdoors has two enemies: the mosquito working the standing water at the bottom of the garden, and the Highland midge that can empty a campsite by nine o’clock. Insect repellent coils remain one of the cheapest, lightest answers to both — a smouldering spiral that costs pennies an hour to run, needs no batteries, no gas canister and no plug, and slips into a rucksack pocket alongside the tent pegs. Choose the wrong one, though, and you either spend the evening breathing smoke for nothing, or you site a pyrethroid somewhere it can harm a cat or a garden pond.

This is a research-based guide. It compares manufacturer specifications, published UK health and regulatory guidance, and verified owner feedback across retailer review pages — it does not claim hands-on testing. Prices shift constantly between retailers and across seasons, so every figure below is an approximation for guidance only.

At a Glance: The Best Insect Repellent Coils and Alternatives in 2026

The short answer: for traditional smouldering coils, the best-evidenced UK pick is Lifesystems Mosquito Coils, because it is the one product in the category whose active ingredient, burn time and treated volume are all published by the manufacturer. If you want no smoke and no open flame — for a patio table with children around it, or anywhere a festival’s site rules forbid smouldering items — a Thermacell device is the compliant alternative.

How Insect Repellent Coils Work — and How to Choose

A mosquito coil is, mechanically, a slow-burning incense stick coiled into a spiral. The sawdust-and-binder base smoulders rather than flames, releasing a steady plume of insecticidal vapour that disrupts an insect’s nervous system and its ability to locate you. Because the active ingredient rides on smoke particles, coils perform best in still air, where vapour accumulates around a seating area or a camping chair. In a stiff breeze it disperses before it can do much — which is why placement and weather matter as much as the label.

Prallethrin, allethrin and citronella: what is actually in them

Most effective coils sold in the UK use a synthetic pyrethroid rather than a plant oil. Lifesystems’ own product page states its coils contain prallethrin 0.036% w/w as the active ingredient, and the same page states each coil treats approximately 20 m³ / 700 ft³. Thermacell’s mat-based system uses allethrin, a closely related compound, which is heated by a butane cartridge rather than burned.

Citronella coils — the cheap multipacks found on Amazon UK, in garden centres and at retailers such as Wilko and B&Q — rely on plant-derived citronella oil instead. The percentage is rarely disclosed on budget packs, which makes them hard to compare on anything except price and pack count. They smell pleasant and cost little, but owner reviews generally describe them as mildly useful rather than decisive. If midges or mosquitoes are genuinely bad, a pyrethroid coil is the better bet; citronella is a background deterrent.

Coverage, burn time and what the numbers really mean

Two specifications carry the most weight. The first is burn time per coil: Lifesystems quotes up to 4½ hours per coil, which is why a pack of ten is listed as 45 hours of protection in total. Most budget coils sit somewhere between three and five hours, and wind, damp ground and poor placement can cut that noticeably.

The second is treated volume. Lifesystems’ 20 m³ figure is a useful mental anchor: that is roughly the air inside a small three-person tent, or the seated space around a camping table. Outdoors, that volume disperses far more freely than it would indoors, so treat any coverage claim as a guide to the area directly downwind of the coil rather than a guaranteed force field.

Working out running cost before you buy

The honest way to compare coils, citronella and Thermacell is cost per hour, and it is simple arithmetic: divide the pack price by the hours the manufacturer claims for the pack. For Lifesystems at around £6–£9 per ten-pack, that is approximately £6 ÷ 45 hours ≈ 13p per hour, rising to approximately £9 ÷ 45 hours ≈ 20p per hour at the top of the price range. Both figures sit at the cheap end of outdoor insect protection, and the difference between them is only about seven pence an hour — worth checking, but not worth a detour across town.

Practical placement

Coils belong on the supplied metal stand, on bare earth, gravel or a metal tray, and never directly on dry grass, decking or a picnic blanket. Site the coil upwind of the people you are protecting so the plume drifts across the seating area, and keep food, drinks and children’s hands out of the smoke path. Two coils placed at opposite corners of a patio work better than one in the middle, because the vapour is doing area work rather than person work.

Safety Before You Buy: UK Rules and Health Guidance

They are regulated products. Insect repellent coils are regulated biocides in Great Britain. Before buying anything unfamiliar, check that the product appears on the GB Biocidal Products Register maintained by the Health and Safety Executive (HSE) — the register is searchable at hse.gov.uk/biocides. An authorised product has had its active ingredient, label claims and instructions assessed; an unauthorised import has not.

Outdoor use only. Both the World Health Organization and the UK Health Security Agency note that coil smoke contains particulates and carbon monoxide. UKHSA guidance recommends outdoor use only. This is not a marketing caveat: a smouldering coil in an enclosed space concentrates both combustion by-products and insecticide where you are breathing them.

Asthma and lung conditions. Asthma + Lung UK explicitly flags smouldering coil smoke as an asthma trigger. If anyone in your household has asthma or another respiratory condition, a smoke-free alternative is the sensible choice rather than a compromise.

Cats. Pyrethroids — including prallethrin and allethrin — are acutely toxic to cats. The Veterinary Poisons Information Service (VPIS) and RCVS-registered veterinary practices routinely warn about this class of compound, because cats metabolise pyrethroids poorly and exposure through smoke, residue on fur, or a chewed coil can cause serious neurological signs. Keep coils and Thermacell mats away from cats entirely, and never burn one in a conservatory or on a balcony a cat shares.

Garden ponds and watercourses. Pyrethroids are acutely toxic to aquatic invertebrates and carry an acute aquatic hazard classification — the basis of warnings from the Environment Agency and the ECHA. Do not burn coils beside a pond, and dispose of stubs and ash in the bin, not on the soil or in water.

Never indoors or in a tent. Coils and Thermacell units are outdoor-only products. There is no safe configuration for tent, awning, campervan or enclosed-space use.

The Best Insect Repellent Coils and Smoke-Free Alternatives for 2026

1. Lifesystems Mosquito Coils — best overall

Who it’s for: campers, gardeners and festival-goers who want a traditional smouldering coil and would rather buy the one product whose numbers are actually published.

What you get, per Lifesystems’ own stated specifications: a pack containing 10 coils and 2 metal stands, weighing 120 g and measuring 145 × 135 × 15 mm — small enough to live permanently in a daypack lid. The active ingredient is prallethrin 0.036% w/w. Burn time is up to 4½ hours per coil, giving 45 hours per pack, and each coil is stated to treat roughly 20 m³ / 700 ft³.

Standout strength: the transparency. Lifesystems is the one brand in this category that publishes active-ingredient concentration, per-coil burn time and treated volume on the product page, which means you can compare it against anything else on the shelf instead of guessing. The inclusion of two metal stands also matters more than it sounds — a coil without a stand has to be balanced on something improvised, which is how people end up scorching decking.

Honest caveat: 45 hours is a still-air figure. On an exposed coastal pitch or a breezy hillside, expect noticeably less effective coverage as the plume disperses, and budget on replacing coils sooner than the arithmetic suggests.

Verdict: the default UK buy for smouldering coils — best-evidenced, sensibly packaged and cheap to run.

Where to buy: stocked at Go Outdoors, Cotswold Outdoor and Amazon UK. Prices vary by retailer and season; a ten-pack typically lands somewhere around £6–£9 in 2026 UK outdoor retail, so it is worth checking each listing before ordering.

2. Citronella Coils — best budget background deterrent

Who it’s for: anyone who wants a low-cost, pleasant-smelling coil for a sheltered patio on an average British evening, rather than a serious midge or mosquito defence.

What you get: multipacks of plant-oil coils sold under garden brands and own-label lines. Tikki and Burgon & Ball are among the citronella coil names listed through UK garden retailers, alongside the anonymous multipacks that turn up on Amazon UK and at Wilko and B&Q. The active ingredient is citronella oil, and here is the honest part: the concentration is rarely disclosed on budget packs, so unlike the Lifesystems label you cannot compare them on active-ingredient strength — only on pack size, price and whether an ingredient is listed at all.

Standout strength: cost and tolerance. Citronella coils are the cheapest way to put a deterrent plume over a patio table, and the smell is inoffensive enough that people actually use them rather than saving them for a special occasion.

Honest caveat: owner consensus on Amazon UK and Trustpilot repeatedly describes citronella coils as a mild deterrent rather than a decisive one — pleasant background coverage in light conditions, but not something owners report as reliable when midges or mosquitoes are heavy. If you are buying specifically for a bad midge night, spend the extra couple of pounds on a pyrethroid coil.

Verdict: a cheap, low-commitment background option — just do not expect it to hold a line against a serious midge hatch.

Where to buy: garden centres and UK retailers including Wilko, B&Q and Amazon UK, where listing quality varies; prefer any pack that names its active ingredient over one that does not.

3. Thermacell Patio Shield / MR-300 — best smoke-free alternative

Who it’s for: households with children, asthma or a cat; patio users who do not want smoke drifting over food; and anyone heading to a festival that bans smouldering items.

How it works — and why it is not a coil: a butane cartridge heats an allethrin-impregnated mat, releasing repellent vapour without combustion of the repellent itself. That changes the consumable economics completely, because you are buying two things rather than one.

What the specifications say: Thermacell’s own spec gives a treated zone of approximately 4.5 m × 4.5 m. The butane cartridge is rated at roughly 12 hours and each mat at roughly 4 hours, so one cartridge covers about three mat changes.

Standout strength: no smoke and no open flame. That combination is what makes it acceptable at events and on balconies where a smouldering coil is not, and it removes the particulate and carbon monoxide exposure that UKHSA and Asthma + Lung UK flag.

Honest caveat: running cost. Refill packs typically cost around £8–£12, covering one butane cartridge (about 12 hours) and the mats that go with it, so dividing that out lands well above the 13p–20p per hour the Lifesystems pack works out at. You are paying a premium for smoke-free operation, not for cheaper evenings.

Verdict: the right buy when smoke or open flame is the deal-breaker — and the only one of these three that fits a no-flame venue or a cat-owning household.

Where to buy: Screwfix, Amazon UK and outdoor retailers. The device itself typically costs around £30–£45, with refill packs around £8–£12; verify current pricing and pack contents, since cartridge-and-mat bundles differ between listings.

Midges Specifically: What Actually Works

The Scottish biting midge, Culicoides impunctatus, is a different problem from the garden mosquito, and the difference shapes what you should buy. NatureScot’s guidance on midge avoidance emphasises that smoke and air movement matter as much as insecticide: midges are weak fliers, so a smouldering coil’s plume and even a stiff breeze do a lot of the work before any active ingredient is involved. That is why a coil that underwhelms against mosquitoes on a still patio can still make a Highland evening bearable, and why sitting in the open rather than in a sheltered hollow helps.

That said, pyrethroid coils have only some effect on midges, and they should not be your only line of defence. DEET and picaridin topicals remain UKHSA’s recommended primary defence for biting insects; treat coils, citronella and Thermacell units as area support for a pitch or a seating area, layered on top of something you have applied to yourself.

Festivals: What You Can and Cannot Take

Many UK festivals ban smouldering items and open flames in their published site rules, and those rules are written with fire risk, not insect control, in mind — but they apply to your mosquito coils all the same. Check the specific event’s site rules page before you pack, because the wording varies: some prohibit naked flames, some prohibit anything that smoulders, and some simply ban all off-ground fires. A Thermacell-class device or a topical repellent is the compliant option where a coil is not, and a topical repellent is the only option inside a tent regardless of which festival you attend.

FAQ

Are insect repellent coils legal in the UK? Yes, provided the product is authorised. Insect repellent coils are regulated biocides in Great Britain, and authorised products appear on the GB Biocidal Products Register maintained by the Health and Safety Executive. You can search that register at hse.gov.uk/biocides before buying, which is worth doing for unfamiliar online listings where the active ingredient is not clearly stated. An authorised product has had its claims and label instructions assessed; an unauthorised import has not.

Can I use mosquito coils inside a tent? No. Both the World Health Organization and the UK Health Security Agency note that coil smoke contains particulates and carbon monoxide, and UKHSA guidance recommends outdoor use only. A tent concentrates both the combustion by-products and the insecticide exactly where you are sleeping. Coils and Thermacell units are outdoor-only products with no safe enclosed-space configuration.

Are mosquito coils dangerous to cats? They are a genuine risk. Pyrethroids including prallethrin and allethrin are acutely toxic to cats, as the Veterinary Poisons Information Service and RCVS-registered veterinary practices regularly warn. Exposure can happen through inhaled smoke, residue transferred to fur, or a cat chewing a coil or a Thermacell mat. If you share a home with a cat, a smoke-free device used strictly outdoors and stored out of reach is the safer route.

Will coils harm my garden pond? Pyrethroids are acutely toxic to aquatic invertebrates and carry an acute aquatic hazard classification, the basis of the Environment Agency’s and the ECHA’s warnings on this class of compound. That means pond life — not just fish, but the invertebrates the whole pond ecosystem rests on — is at risk from drift, ash and discarded stubs. Do not burn coils beside a pond, and put stubs and ash in the bin rather than on the soil.

How long does a coil actually last, and how cheap is it per hour? Lifesystems’ own figures are up to 4½ hours per coil and 45 hours per ten-coil pack, so dividing a typical pack price of around £6–£9 by 45 hours gives roughly 13p–20p per hour. Most budget coils sit somewhere between three and five hours per coil, so the pack mathematics is worth checking before you assume the cheaper multipack is better value. Bear in mind that wind and damp ground can shorten real-world burn times.

Do citronella coils work as well as pyrethroid coils? Generally not, on the evidence available. Citronella coils rely on plant-derived oil, and the concentration is rarely disclosed on budget packs, so there is little to compare; owner reviews on Amazon UK and Trustpilot describe them as a mild rather than decisive deterrent. Prallethrin and allethrin coils, by contrast, publish their active-ingredient percentage and burn time. Citronella is best treated as background coverage on a mild evening.

What is the difference between a coil and a Thermacell? A coil smoulders, carrying its insecticide on smoke particles and producing particulates and carbon monoxide in the process. A Thermacell device uses a butane cartridge to heat an allethrin mat, so there is no smoke and no open flame, and the manufacturer quotes a treated zone of roughly 4.5 m × 4.5 m. The trade-off is cost: refill packs run around £8–£12 and cover a 12-hour butane cartridge with 4-hour mats, which works out more per hour than a smouldering coil.

Can I take insect repellent coils to a festival? Only if that festival’s published site rules permit smouldering items. Many UK festivals ban them alongside open flames, and the rules are usually phrased around fire risk rather than insects, so a coil can be excluded even though it seems harmless. Check the specific event’s site rules page, and plan on a Thermacell-class device or a topical repellent as the compliant alternative.

The Bottom Line

For a traditional smouldering coil, Lifesystems Mosquito Coils are the best-evidenced UK pick: prallethrin at 0.036% w/w, 10 coils and 2 metal stands, up to 4½ hours per coil and 45 hours per pack, at roughly 13p–20p per hour from a pack priced around £6–£9. Citronella multipacks are the cheap background option for a sheltered patio, provided you accept that they are a mild deterrent. And if smoke or open flame is the obstacle — children, asthma, a cat, or a festival site rule — the Thermacell Patio Shield is the compliant, smoke-free alternative at a higher cost per hour. Whichever you choose, keep it outdoors, keep it off the ground, and keep it away from ponds and cats.