No — electronic ultrasonic repellents do not effectively repel or deter rats. Multiple peer-reviewed studies (including research published in pest management journals) have found that rats habituate to ultrasonic frequencies within days of initial exposure. After habituation, the devices have no measurable effect on rat behavior or population.

How Ultrasonic Repellents Supposedly Work

These devices plug into a wall outlet and emit ultrasonic sound waves at frequencies above what people can hear — usually between 20,000 and 65,000 Hertz (Hz). The manufacturers claim that these sounds are uncomfortable or even painful for rats, so the rats will leave the area or avoid entering it.

What the Science Shows

Scientific studies over several decades have tested these devices in both laboratory and real-world settings.

• No reliable evidence: Most well-designed experiments have found that these devices do not drive rats away or prevent them from returning. Some studies show that rats might change behavior for a couple of days, but they quickly return, ignoring the sound completely.
• Rats get used to the sound: Even when ultrasonic noise bothers them initially, rats adapt if food, water, or shelter is available. They simply tune it out.
• Limited coverage: Ultrasonic sound waves don't travel far and cannot penetrate walls, furniture, or ceilings. Only a small portion of a room is affected — rats avoid the sound by moving to other areas.
• Professional organizations agree: Public health agencies, pest control experts, and consumer protection groups almost all say that ultrasonic repellents do not work effectively as advertised.

The FTC Warning

The US Federal Trade Commission (FTC) has taken enforcement action against manufacturers of ultrasonic pest repellents for making unsupported effectiveness claims. When purchasing these products, there are no peer-reviewed studies demonstrating sustained effectiveness against rats.

Price Does Not Make Them More Effective

No price point makes ultrasonic repellents effective. $20 plug-in units and $200 professional-grade emitters have both failed to demonstrate sustained rodent deterrence in controlled studies. The mechanism itself — sound habituation — applies regardless of intensity or price.

Common Problems and Misconceptions

• Marketing claims are exaggerated: There is no independent proof to support claims of eliminating 100% of rats.
• No long-term impact: Even if rats are briefly bothered, they return within days or find new routes into your home.
• No effect on nests: Ultrasonic sound waves don't travel through walls, attics, or crawl spaces — rats already nesting in hidden areas are completely unaffected.
• Can interfere with other pets: The devices may cause irritation to pet rodents like hamsters and guinea pigs — but not to the rats you want gone.

What Actually Works for Getting Rid of Rats

• Remove food and water sources: Sealed containers, clean-up of crumbs, no pet food left out overnight
• Seal entry points: Close gaps, holes, and cracks in walls, foundations, doors, and windows — even the smallest opening can let a rat in
• Use physical traps: Snap traps or live-catch traps in high-activity areas, checked regularly
• Maintain cleanliness: Clear clutter, garbage, and potential nesting materials inside and outside
• Call a professional: Pest control professionals identify access points, set traps, and give recommendations specific to your home

Should You Use Ultrasonic Repellents?

No. There is no consistent scientific evidence that they work, and most pest management professionals do not recommend them. Your time and money are better spent on proven methods: blocking entry points, removing food sources, trapping, and — if needed — professional pest control. Relying on ultrasonic devices alone will almost always lead to continued rat problems.

Call Anchor Pest Services at (603) 785-0118 for proven, eco-friendly rat control across New Hampshire.

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