How to Upgrade Halogen Downlights to LED: Three Retrofit Options Compared

Guides & How-Tos
Jan 27 2026

Upgrading old halogen recessed lighting is one of the simplest ways to improve energy efficiency, lighting quality, and aesthetics in a home. Not all retrofit options are equal. Each comes with its own benefits and potential pitfalls. Here is a breakdown of the three most common approaches, along with Halcyon’s recommendations.

Option 1: Lamp-Only Upgrade

The quickest and cheapest way to switch is to replace halogen lamps with MR16 LED lamps. In most cases, this is more of a short-term fix than a lasting solution.

Because MR16 LEDs are limited by their small size and usually paired with outdated/aging halogen transformers, the results are often disappointing. Lifespans are shorter, dimming is patchy, and flickering is common. Many older transformers also require a 20W minimum load which is far higher than today’s 3–6W MR16 LEDs. Homeowners often discover too late that a simple lamp swap snowballs into a costly electrician callout.

Halcyon Tip: If retaining MR16s is a must, replace the old transformers with Halcyon ULTRA70 or ULTRA105 electronic transformers. These feature a true 0W minimum load for stable, flicker-free performance.

View Ultra Transformers

Option 2: Retrofit LED Module and Driver

A step up from lamp-only upgrades, retrofit LED modules are an excellent choice when housings and trims are still in good condition or when dealing with unusual cutout sizes that make full replacements difficult.

Unlike MR16s, dedicated LED modules with matched drivers are not restricted by tiny form factors or compromised by legacy transformer technology. This means longer lifespans, smoother dimming, and no need to keep spare MR16s in the cupboard.

Halcyon Tip: Retrofitting into older control systems such as C-Bus requires care. Always check the minimum loads on dimming modules. LED upgrades significantly reduce circuit loads and overlooking this detail can cause flicker and instability.

View Retrofit Module Kits

Option 3: Complete Replacement

If trims are looking tired or a more modern style is desired, replacing the entire fitting is the best option. Halcyon offers a wide range of retrofit downlights designed to suit all common cutout sizes. This provides homeowners with a fresh, cohesive look along with the performance of dedicated LED fixtures.

Halcyon Tip: For large cutouts in residential projects, avoid the temptation of installing oversized commercial fittings. Instead, use an adapter plate for a clean finish. For example, Halcyon’s R750 Smart Tilt Downlights feature an optional flush-fit adapter plate accessory that retrofits 100–135mm cutouts without overwhelming the room with excess light.

View R750 Downlight Kit & Optional Adapter Accessory

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