Best mosquito repellents under $25

Four jobs, and twenty-five dollars buys any one of them

"Mosquito repellent" covers four different jobs. Buying the wrong one is the usual reason people conclude that nothing works.

1. Keep them off my skin. A topical repellent with a registered active. This is the only category that reliably prevents a bite on your arm, and it works by making you hard to locate rather than by killing anything.

2. Keep them out of this chair. An area repeller — a heated mat or cartridge that releases a repellent vapor and produces a protected bubble around a seating area, roughly fifteen to twenty feet across depending on the unit and the wind, per the manufacturer. Minutes to effect, nothing on your skin.

3. Reduce the number in my yard. A yard concentrate sprayed on the vegetation mosquitoes rest in during the day — the shaded undersides of leaves, the hedge base, the long grass. A residual treatment, applied every few weeks in season.

4. Stop next week's mosquitoes. A larvicide in standing water you cannot drain. The only one of the four that attacks the population rather than the symptom.

Twenty-five dollars will buy you any single one of these, and the right choice depends entirely on which sentence you just said out loud. If it was "I cannot sit on my patio", buy the area repeller. If it was "I am covered in bites after walking the dog", buy the skin repellent.

On skin: what the actives do

Four actives are registered for repelling mosquitoes and all four are available cheaply.

DEET is the reference standard and still the most dependable product under heavy pressure. Concentration governs duration rather than strength: around 20-25% gives several hours, and going much higher mostly buys more hours, not more protection. It will soften some plastics and synthetic fabrics, which is its practical drawback.

Picaridin performs comparably to DEET at 20% in published comparisons, does not damage plastics or gear, and is noticeably more pleasant to wear — lighter, close to odourless. For families and for anyone handling fishing tackle, watch straps or sunglasses, it is the easier recommendation.

Oil of lemon eucalyptus, as the refined active, is the one plant-derived repellent with real registered standing. Shorter duration than DEET or picaridin, and labeled not for use on children under three. Worth knowing the distinction: the registered refined active is not the same thing as lemon eucalyptus essential oil from a shelf of home remedies.

IR3535 is the mildest of the four and the most commonly found in family-branded formulations.

The deeper comparison is DEET vs picaridin, the skin-specific roundup is best mosquito repellents for skin, and for children and dogs the right pages are kid-safe mosquito repellents and mosquito repellent for dogs.

Read the label as the governing document in all four cases. Age restrictions, reapplication intervals and whether it can go on a face are on there, and they vary.

In the yard: the concentrate and its limits

A hose-end or pump-sprayer concentrate treats the places adult mosquitoes rest during the day, which is not the open lawn but the shaded, humid, sheltered foliage: the undersides of hedge leaves, ivy, the base of shrubs, the dense corner nobody weeds.

It works, it lasts a few weeks depending on rain, and it is cheap per application. Two honest caveats. It is an insecticide, so it is not selective — it is going on vegetation where pollinators forage, which means treating at dusk, avoiding anything in flower and keeping well away from water. And it is a treatment, not a fix: untreated mosquitoes fly in from next door the following week.

If dogs are on the grass, the choice narrows, and pet-safe mosquito yard sprays and wondercide vs cutter cover the trade-off between a botanical spray and a synthetic residual.

The free part that beats all of it

Mosquitoes breed in still water measured in tablespoons, and the ones biting you were almost certainly born within a few hundred feet of where you are standing. Weekly, walk the property and tip out:

• plant pot saucers and the trays under them
• the wheelbarrow, the kids' paddling pool, a bucket
• blocked gutters and the sagging corner of a tarp
• bird baths — refresh, do not just top up
• the dog's water bowl, the recycling bin lid, an old tire
• the drip tray under the air-conditioning unit

For water that has to stay — a pond, a rain barrel, a gully, a water feature — a Bti larvicide is the answer. Bti is a bacterium specific to mosquito and blackfly larvae, which is why dunks and granules are usable in a rain barrel and around fish and wildlife. Granules work faster and are easier to dose in a small volume; briquettes last longer in a steady body of water. See do mosquito dunks work and mosquito dunks vs bits.

Twenty minutes a week here does more than any single purchase on this page, and the larvicide that supports it costs a fraction of your twenty-five dollars.

Where not to spend the money

Citronella candles. They produce a modest effect in still air directly beside the candle, and much less than people expect. Compared against a heated-mat repeller they are not close — thermacell vs citronella candles.

Ultrasonic repellers, wearable or plug-in. The claim does not survive testing. Do ultrasonic repellers work is about rodents and the same pattern applies here.

Bug zappers, if bites are the complaint. They kill light-seeking insects, which mosquitoes are not. Do bug zappers work.

Wearable bracelets and clip-ons without a registered active. The protected volume is, at best, the few inches around the device.

The twenty-five dollar shopping list

If you are starting from nothing and have exactly twenty-five dollars: buy the cheap area repeller for the patio if sitting outside is the problem, or the picaridin spray if being outside and moving is the problem. Then, next payday, add a tub of Bti granules and spend twenty minutes a week emptying water. That combination — zone, skin, source — is the whole of effective mosquito control, and it is remarkably cheap. How to get rid of mosquitoes in your yard puts it in order.