Electric Fly Killers: Why Changing the Bulb Really Matters

Monday 19/01/2026

Change the Bulb, Beat Fly Season

Electric fly killers are easy to ignore, until flies become a problem. Many small restaurants and cafés assume their unit is working because the light is on. The truth? A glowing bulb doesn’t mean it’s doing its job.

Let’s break down why bulb changes matter, the difference between UVA, LED, and retrofit lamps, and why annual servicing is essential.

The Big Myth: “The Light’s On, So It’s Working”

Flies aren’t attracted to visible light, they’re attracted to UVA output. Over time, that UVA fades, even though the bulb still lights up.

After around 12 months, a fly killer bulb can lose up to half its effectiveness. That means fewer flies caught and more flying around your food areas.

Fly Killer Bulbs Explained (Without the Jargon)

Traditional UVA Fluorescent Bulbs

Traditional UVA fluorescent bulbs are the most common type found in older units, offering strong attraction when new, but their effectiveness drops over time, which is why they must be replaced annually.

LED Fly Killers

A newer, energy‑efficient option that offers lower running costs, a longer lifespan, and more consistent UVA output. Quality matters, cheap LEDs don’t always attract flies effectively.

Retrofit LED Bulbs

Retrofit LED bulbs are an easy upgrade for existing units, fitting into older fly killers, reducing energy use, and requiring less frequent bulb changes.

Only specialist fly killer LEDs work, standard UV lamps won’t.

Why Annual Servicing Is Worth It

For small restaurants and independent operators, annual servicing is often skipped, and that’s where problems start.

A proper service includes:

Replacing bulbs and glue boards

Cleaning the unit

Checking electrical safety

Making sure it’s positioned correctly

It keeps your fly killer effective, compliant, and inspection-ready.

Keep Your Fly Control On Track

Electric fly killers aren’t “fit and forget.” Without regular bulb changes and servicing, they quickly lose their impact. Whether you’re using UVA, LED, or retrofit bulbs, an annual service is a simple way to keep flies under control, and your business protected

Keep your fly killer working at full strength, shop our full range of replacement bulbs here:
Replacement Bulbs

No fly killer installed yet? Protect your business, customers, and hygiene standards with our electric fly killer range: Electric Fly Killers