Outdoors & Fitness
The Best Mosquito Repellent Devices: 4 Compared (and One to Skip)
We compared a rechargeable zone repeller, larvicide dunks, a fuel-powered repeller and a bug zapper against mosquito-control experts' guidance on what works.
The short version
The Thermacell E55 Rechargeable Mosquito Repeller is our pick: it creates a 20 foot zone of repellent around a patio, runs 5.5 hours per charge, and is reviewed by the EPA. Summit Mosquito Dunks are the value pick for stopping mosquitoes at the source, killing larvae in standing water for 30 days or more. The Thermacell Fuel-ZoneGuard Base suits anyone who wants no charging, at the cost of buying fuel and mats. Skip bug zappers like the Flowtron BZ-18: the American Mosquito Control Association says zappers are not effective at controlling biting mosquitoes, and mosquitoes made up only a small share of what zappers killed in studies. Best for: anyone who wants a usable patio or deck on summer evenings.
Our picks at a glance
- Thermacell E55 Rechargeable Mosquito Repeller - Buy. A rechargeable repeller that creates a 20 foot zone of repellent with no spray or smoke.
- Summit Mosquito Dunks - Buy. Floating Bti dunks that kill mosquito larvae in standing water for a month or more.
- Thermacell Fuel-ZoneGuard Base - It depends. A fuel-powered zone repeller with no charging, but a smaller zone and more refills.
- Flowtron BZ-18 Outdoor Bug Zapper - Skip. A UV bug zapper that kills plenty of insects, just not many of the mosquitoes that bite you.
The verdict in 30 seconds
What mattered most
- Method
- Coverage
- Run time
- Active ingredient
- Targets
- Power
Backyard mosquitoes can turn an evening outside into a chore, and the options range from spray-free repellers to traps, zappers and larvicides. Mosquito control professionals have studied many of these devices, and some popular ones do far less than their packaging suggests. We compared a rechargeable zone repeller, a larvicide for standing water, a fuel-powered repeller and a best-selling bug zapper.
A rechargeable repeller that creates a 20 foot zone of repellent with no spray or smoke.
Best for: Patios, decks and campsites where you sit in one area.
- Thermacell says it repels mosquitoes within a 20 foot zone, including species that may carry West Nile, Dengue, Zika and EEE.
- Rechargeable battery with a 5.5 hour run time, reaching full protection in 15 minutes.
- Scent-free and DEET-free, and Thermacell says it is EPA reviewed for safety and effectiveness around people and pets.
- For outdoor use only.
- Repellent cartridges must be replaced, which is an ongoing cost.
- Protection is a zone around the device, so breezy or open spaces are harder to cover.
Floating Bti dunks that kill mosquito larvae in standing water for a month or more.
Best for: Yards with ponds, birdbaths, rain barrels or other standing water.
- Contain Bti, a bacterium that Summit says is deadly to mosquito larvae but harmless to other living things.
- Each dunk covers up to 100 square feet of water and lasts 30 days or more.
- Summit says they are harmless to plants, fish, frogs, turtles and beneficial insects, and labeled for birdbaths and troughs.
- Does nothing about adult mosquitoes already flying.
- Only helps where there is standing water to treat.
- Needs replacing about monthly through the season.
A fuel-powered zone repeller with no charging, but a smaller zone and more refills.
Best for: Campers and occasional users who do not want to charge a battery.
- Thermacell says it repels mosquitoes from a 15 foot zone.
- Runs on a 12-hour fuel cartridge, so there is nothing to charge.
- Reaches full protection in 15 minutes, with no spray or smoke.
- A 15 foot zone versus 20 feet for the E55.
- Needs both fuel cartridges and repellent mats, which last 4 hours each.
- For outdoor use only.
A UV bug zapper that kills plenty of insects, just not many of the mosquitoes that bite you.
Best for: No one looking for mosquito relief.
- A 4000-volt grid that Flowtron says covers up to half an acre.
- Weather-resistant with a non-clogging grid.
- Satisfying if you enjoy hearing insects hit the grid.
- The American Mosquito Control Association says bug zappers are not effective at controlling biting mosquitoes.
- In the studies it cites, mosquitoes made up only 4.1% and 6.4% of what zappers killed, with no significant difference in mosquitoes between yards with and without zappers.
- Most of the catch is harmless or beneficial insects.
- Flowtron suggests adding octenol cartridges to boost mosquito results, an extra ongoing cost.
| Criteria | Thermacell E55 Rechargeable Mosquito Repeller Top pick | Summit Mosquito Dunks | Thermacell Fuel-ZoneGuard Base | Flowtron BZ-18 Outdoor Bug Zapper |
|---|---|---|---|---|
| Verdict | Buy it | Buy it | It depends | Skip it |
| Best for | Patios, decks and campsites where you sit in one area. | Yards with ponds, birdbaths, rain barrels or other standing water. | Campers and occasional users who do not want to charge a battery. | No one looking for mosquito relief. |
| Price tier | $$ · mid-range | $ · budget | $ · budget | $$ · mid-range |
| Method | Heated repellent zone | Larvicide for standing water | Heated repellent zone | UV light and electric grid |
| Coverage | 20 foot zone | Up to 100 sq ft of water per dunk | 15 foot zone | Up to half an acre (maker claim) |
| Run time | 5.5 hours per charge | 30 days or more per dunk | 12-hour fuel, 4-hour mats | Continuous, mains powered |
| Active ingredient | 5.5% metofluthrin | Bti | 21.97% d-cis allethrin | None |
| Targets | Adult mosquitoes nearby | Larvae before they fly | Adult mosquitoes nearby | Mostly other insects |
| Power | Rechargeable battery | None | Fuel cartridge | Mains outlet |
| Evidence | EPA reviewed, per maker | Bti larvicide | EPA reviewed, per maker | AMCA: not effective |
| Best for | Patios and decks | Yards with standing water | No charging | No one |
Which one is right for you?
- Patios, decks and campsites where you sit in one area. Buy it Thermacell E55 Rechargeable Mosquito Repeller
- Yards with ponds, birdbaths, rain barrels or other standing water. Buy it Summit Mosquito Dunks
- Campers and occasional users who do not want to charge a battery. It depends Thermacell Fuel-ZoneGuard Base
- No one looking for mosquito relief. Skip it Flowtron BZ-18 Outdoor Bug Zapper
How we judged the field
Five things decide whether a mosquito device is worth buying: whether there is evidence it reduces bites, how large an area it protects, how long it runs, what it costs to keep using, and whether it targets mosquitoes or everything else. Evidence comes first, because this category is full of products that feel effective but are not. Coverage and run time decide whether it protects the space you actually use.
The field splits into zone repellers, larvicides, traps and zappers, and ultrasonic gadgets. The American Mosquito Control Association has concluded that bug zappers do not control biting mosquitoes and that ultrasonic devices have no repellency value. We picked two zone repellers, a larvicide and a popular zapper, then compared them against that guidance and the makers’ specs.
The Thermacell E55 Rechargeable Mosquito Repeller is the device we would put on a patio table. It heats a repellent cartridge to create a zone that Thermacell says repels mosquitoes within 20 feet, including species that may carry West Nile, Dengue, Zika and EEE. The built-in lithium-ion battery runs 5.5 hours per charge, it reaches full protection in 15 minutes, and there is no spray, smoke or scent. Thermacell says it is independently tested and EPA reviewed for safety and effectiveness around people and pets. It ships with a 12-hour repellent cartridge and a USB cable. The limits are the ones that apply to any zone device: it is for outdoor use only, cartridges are an ongoing cost, and wind or wide-open spaces make a zone harder to hold. For evenings on a deck, it is the most convenient option here.
Summit Mosquito Dunks attack the problem before mosquitoes can fly. Each floating dunk releases Bti, a bacterium that Summit says is deadly to mosquito larvae but harmless to other living things, and covers up to 100 square feet of water for 30 days or more, regardless of depth. Summit says they are harmless to plants, fish, frogs, turtles and beneficial insects, and they are labeled for animal watering troughs, ponds and birdbaths. They do nothing about adult mosquitoes already in your yard, and they only help if you have standing water to treat, so they work best alongside emptying buckets and gutters. You replace them roughly monthly through the season. For yards with ponds, rain barrels or birdbaths, they are an inexpensive way to cut the next generation of biters.
The Thermacell Fuel-ZoneGuard Base is the no-charging alternative. It runs on a 12-hour fuel cartridge that heats a repellent mat, and Thermacell says it repels mosquitoes from a 15 foot zone, reaching full protection in 15 minutes with no spray or smoke. The starter kit includes the repeller, one fuel cartridge and three repellent mats that last 4 hours each. The trade-offs are the zone and the refills: 15 feet instead of the E55’s 20, and two kinds of consumables to buy, since mats run out faster than fuel. It is also for outdoor use only. For camping trips and occasional use where charging a battery is inconvenient, it works well. For regular evenings at home, the rechargeable E55 is simpler to live with. Keep spare mats and fuel in the kit so a trip is not cut short.
The Flowtron BZ-18 Outdoor Bug Zapper is a popular choice that we would skip for mosquitoes. Flowtron says its UV light attracts mosquitoes, flies and other flying insects to a 4000-volt grid, covering up to half an acre, and suggests adding octenol cartridges to boost mosquito results. The American Mosquito Control Association’s view is blunt: bug zappers are not effective at controlling biting mosquitoes. It cites controlled studies in which mosquitoes made up only 4.1% and 6.4% of the daily catch over a season, with no significant difference in mosquito numbers between yards with and without zappers, and notes that most of the catch is non-pest insects. The satisfying zap is mostly moths and beetles. A repellent or larvicide does far more for your evenings. If you already own one, it is harmless to run for moths, but do not count on it for bites.
Thermacell E55 Rechargeable Mosquito Repeller vs Summit Mosquito Dunks: which should you buy?
The Thermacell E55 and Mosquito Dunks work on different parts of the problem. The E55 repels adult mosquitoes from a 20 foot zone around you right now, for 5.5 hours per charge. Mosquito Dunks kill larvae in standing water so fewer mosquitoes hatch over the following weeks.
If you mostly want a comfortable patio tonight, buy the E55. If your yard has ponds, birdbaths or rain barrels, add Mosquito Dunks as well; they cost little and reduce the population over the season. Used together, they cover both the source and the space you sit in.
What to look for
- Evidence, not light shows: zappers and ultrasonic gadgets have poor records against mosquitoes.
- A stated zone size: repellers should say how far protection reaches.
- Run time and refills: check what you need to buy to keep it working.
- Source control: treating or emptying standing water reduces mosquitoes at the start.
- Outdoor rating: zone repellers are designed for outdoor use.
- Safety labeling: follow the label around children, pets and fish.
Our final take
Repel where you sit and stop mosquitoes where they breed. The Thermacell E55 Rechargeable Mosquito Repeller is our pick because it covers a 20 foot zone for 5.5 hours per charge with no spray. Summit Mosquito Dunks are the value choice for standing water, lasting 30 days or more per dunk. The Thermacell Fuel-ZoneGuard Base suits campers who do not want to charge anything. Skip bug zappers like the Flowtron BZ-18: mosquito control experts say they do not control biting mosquitoes, and most of what they kill is harmless. Check labels and ask your veterinarian or local mosquito district if you have questions.
Questions, answered
Do bug zappers kill mosquitoes?
They kill some, but not many. The American Mosquito Control Association says bug zappers are not effective at controlling biting mosquitoes, citing studies where mosquitoes were only 4.1% and 6.4% of the daily catch, with no significant difference in mosquitoes between yards with and without zappers. Most of what they kill are other insects.
Do ultrasonic mosquito repellers work?
The American Mosquito Control Association says numerous studies have found no repellency value in ultrasonic devices. The FTC has also challenged claims for ultrasonic mosquito repellers. Spend your money on a repellent or on removing standing water instead.
What is the best way to reduce mosquitoes in my yard?
Start at the source: empty or treat standing water where mosquitoes lay eggs, such as buckets, gutters, birdbaths and plant saucers. Bti products like Mosquito Dunks kill larvae in water you cannot empty. Then use a repellent, on your skin or as a zone device, when you are outside.
Are Thermacell devices safe around pets?
Thermacell says its repellers are independently tested and EPA reviewed for safety and effectiveness around people and pets, and they are for outdoor use only. Keep devices out of reach and follow the label. Pet birds and fish may need extra care; check the label or ask a veterinarian.
Do zone repellers replace bug spray?
They protect a fixed area, so they work best when you are sitting in one place. Walking the yard or hiking still calls for a skin repellent. Wind and open space can also reduce how well a zone device works.
Deciding between the top two? See our head-to-head: Thermacell E55 Rechargeable Mosquito Repeller vs Summit Mosquito Dunks.
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