Everything you need to know about bifenthrin

Bifenthrin is a synthetic pyrethroid insecticide that controls over 75 pest species, including ants, fire ants, termites, cockroaches, spiders, fleas, ticks and mosquitoes. It works by disrupting their nervous system on contact. It’s sold as a liquid concentrate, granules, or ready-to-use spray, and it has a residual effect lasting 4 to 12 weeks, depending on formulation and location. It is registered in Australia for both home and commercial pest control (APVMA). Below, we cover exactly how to choose the right product, how much to apply, how often to reapply, and how to keep it safe around pets, kids and waterways.

What is bifenthrin?

Bifenthrin is a pyrethroid, a synthetic version of the natural pyrethrins found in chrysanthemum flowers. It belongs to Mode of Action Group 3A and is one of the most widely used pyrethroids worldwide, valued for its broad pest spectrum and long residual activity.

It is neurotoxic to insects, paralysing and killing them within minutes of contact or ingestion. Because it provides strong residual activity, bifenthrin doesn’t need to be sprayed directly onto a pest to work. A

Apply it on or around the target area, and it continues killing insects that cross the treated surface for weeks afterwards.

Bifenthrin can be used indoors and outdoors, in small hiding spots such as crawl spaces and under appliances, and across larger areas including lawns, gardens, shrubs and crops — it isn’t absorbed by plant tissue, so it won’t damage the plants it’s sprayed on. It has low toxicity to humans and mammals when used as directed, but it is highly toxic to aquatic animals and should never be applied near waterways, dams or drains.

How bifenthrin works

Bifenthrin disrupts the sodium channels in an insect’s nervous system, causing paralysis and death, typically within minutes of exposure. This ‘knockdown’ effect, combined with a residual film that keeps working long after spraying, is why bifenthrin is rated among the most effective broad-spectrum insecticides available to Australian households, farms and pest professionals.

Which pests does bifenthrin control?

Bifenthrin is registered to control more than 75 insect and arachnid species, making it one of the broadest-spectrum insecticides on the market. Common targets include:

Ants, including fire ants
Termites and borers
Cockroaches
Spiders
Fleas and ticks
Mosquitoes and midges
Armyworms, crickets and grasshoppers
Silverfish, earwigs, centipedes and millipedes
Beetles, moths, wasps and stink bugs

Figure 1: Pest categories controlled by bifenthrin — Specialist Sales

Bifenthrin application methods: liquid, granular or ready-to-use?

Bifenthrin is available in three main forms, each suited to different treatment areas and infestation levels.

Liquid bifenthrin

Liquid concentrate is the most versatile and cost-effective option for treating lawns, gardens and building exteriors. Mix your chosen product with water to label strength and apply with a sprayer — ideal when you’re covering a larger area.

Granular bifenthrin

Granules are well suited to lawn and soil-dwelling pests. Distribute with a broadcast spreader, then water in lightly (unless the label says otherwise) to activate the treatment and move it into the root zone.

Ready-to-use bifenthrin sprays

Ready-to-use sprays need no mixing and are the fastest option for indoor spot treatments, cracks, crevices, skirting boards and small outdoor areas.

Figure 2: Choosing the right bifenthrin format — Specialist Sales

Best bifenthrin products in Australia

There’s a range of generic and branded bifenthrin products across liquid, granular and ready-to-use formulations. Here’s what our team recommends, based on concentration, application and typical use case.

Figure 3: Bifenthrin product comparison — Specialist Sales

Product recommendations at a glance

Zeus Termiticide and Insecticide — Pack sizes: 1L, 5L, 20L | From $95.00 incl. GST. 100 g/L residual insecticide for common household and crop pests.
AntagonistPro Residual Insecticide — Pack sizes: 1L, 5L | Polymer-enhanced formulation — Australia’s only polymer-enhanced bifenthrin, built to outlast standard pyrethroid treatments.
Bifenthrin Ultra 300EC Insecticide — Pack sizes: 5L, 10L, 20L | broad-spectrum insecticide and miticide for agricultural use.
Surround Termiticide — Pack sizes: 1L, 5L | Controls termites plus common household pests; also protects fence posts and service poles.
Surefire Mosquito & Midge Slayer — Pack sizes: 1L | Knockdown and residual treatment for mosquitoes and midges on external surfaces.
Venom Professional 100SC Insecticide — Pack sizes: 5L | Registered for 100+ pest species — a commercial pest control standard for turf and ornamentals.
Surefire Fivestar Insecticide — Pack sizes: 1L, 5L, 20L | Water-based formulation for spiders, ants and mosquitoes, indoors and out.
Surefire Antstar Granular Insecticide — Pack sizes: 500g, 2.5kg, 10kg | Granular treatment for ticks, fleas, ants and other turf pests — knockdown or preventative use.
Bifenthrin Ultra 300ED Insecticide — Pack sizes: 5L, 10L | High-load formulation, non-selective, broad-spectrum insecticide with residual properties.

Bifenthrin application rates and how often to reapply

Bifenthrin is a residual active ingredient, so it keeps working for days, weeks or months after application. As a general rule, outdoor treatments need reapplying every 4 to 8 weeks, while indoor treatments can last up to 12 weeks, but always follow the specific rate and interval on your product’s label first.

Figure 4: Bifenthrin reapplication and dosage quick reference — Specialist Sales

Three factors most affect how often you’ll need to reapply:

Pest pressure: high-activity areas and difficult infestations often need more frequent treatment than the standard label interval.
Environmental conditions: heavy rain can wash away outdoor treatments, so reapply sooner after significant rainfall.
Product formulation: higher-concentration and polymer-enhanced products generally hold their residual activity for longer; always check the label for the exact interval.

Step-by-step: using bifenthrin to treat an ant infestation

Ants are one of the most common reasons Australian households reach for bifenthrin. Here’s a straightforward treatment plan our team recommends:

Identify entry points and nests

Trace ant trails back to where they’re entering the building and, if visible, locate the nest outdoors.

Choose your format

Liquid concentrate for a full perimeter treatment, granules for lawn nests, or a ready-to-use spray for a quick indoor spot treatment.

Mix and apply to the label rate

Follow the label’s mixing ratio exactly. Under-dosing reduces effectiveness and over-dosing wastes product and increases risk to non-target species.

Treat the full perimeter, not just the trail

Apply around door and window frames, foundations, weep holes and any cracks or gaps, as well as the nest site itself.

Keep pets and children clear until dry

Allow treated surfaces to dry completely; this usually takes a few hours. Make sure surfaces are dry before allowing pets or children back into the area.

Monitor and reapply on schedule

Recheck activity after a week; reapply outdoor treatments every 4–8 weeks or sooner after heavy rain.

Call a professional for persistent infestations

If ants return quickly after treatment, a licensed pest technician can identify nest locations you can’t reach and apply commercial-grade product.

Is bifenthrin safe to use around pets?

One of the clearest benefits of bifenthrin over some other fast-acting insecticides is that it’s safe for use around humans and most pets once it has dried on the treated surface. Dried bifenthrin residue doesn’t affect dogs, cats, or other mammals, though you should never spray it directly onto pets to control fleas or ticks. Use a product specifically labelled for that purpose instead.

A few safety tips for pet owners:

Keep pets away from the treatment area during application.
Let treated areas dry completely; this often takes a few hours, depending on conditions — before letting pets back in.
Store bifenthrin products well out of reach of pets.

Ingesting concentrated bifenthrin or direct exposure to a freshly sprayed area can still be harmful. Contact your vet immediately if you suspect your pet has been exposed.

Is bifenthrin safe for the environment?

Bifenthrin is highly toxic to aquatic animals and should never be applied near waterways, dams, drains or ponds. It can also be semi-toxic to birds, so pet owners with aviaries or outdoor birds should take extra care with placement and drift. In Australia, bifenthrin remains a registered active constituent; the APVMA has nominated it for reconsideration after 2029, meaning existing product registrations and label directions continue to apply—always check you’re using the current approved label for your product and use.

Bifenthrin FAQs

Is bifenthrin the same as permethrin?

No. Both are synthetic pyrethroids, but they’re different active constituents with different label registrations, target pests and formulations. Always check the specific active ingredient on the label rather than assuming two pyrethroid products behave the same way.

How quickly does bifenthrin work?

Bifenthrin typically knocks down insects within minutes of contact, with the residual film continuing to kill pests that cross the treated surface for weeks afterwards.

Can I apply bifenthrin and a herbicide at the same time?

Some bifenthrin products can be tank-mixed with certain herbicides or fungicides — Bifenthrin Ultra 300EC, for example, is labelled for combined agricultural use. Always check both product labels for compatibility before mixing.

Is bifenthrin approved for organic use?

No. Bifenthrin is a synthetic pyrethroid, not a naturally derived or certified-organic input.

Do I need a licence to use bifenthrin at home?

Household bifenthrin products don’t require a licence for domestic use — just follow label directions. Commercial pest control application generally requires a pest management technician’s licence under your state’s regulations.

Where can I buy bifenthrin products in Australia?

Specialist Sales stocks a full range of liquid, granular and ready-to-use bifenthrin products, with free and fast shipping Australia-wide.

As an active ingredient, bifenthrin is amongst the best, providing broad-spectrum pest control against more than 75 insect species. With a range of fast-acting, powerful products to suit home gardens, farms and commercial sites, integrating bifenthrin into your pest management plan is straightforward — just read and follow the product label to keep yourself, your pets and the environment safe.

Got questions about the right bifenthrin formulation for your situation? The Specialist Sales team has decades of combined experience advising Australians on safe, effective pest control — contact us and we’ll be glad to help.