Landscape lighting lamps

Replace halogen landscape bulbs with LED

Identify the base, match the beam spread and color, and pick the LED rated as the halogen equivalent. Then re-check the transformer: the load drops, and the voltage at the fixtures usually rises.

  • Same base, same beam
  • 20 W → about 4 W LED
  • 2700K reads warm
  • Size at 80% load

Checked against manufacturer specifications and our live catalog · Updated October 2026

FX Luminaire NP up light aimed at a tree
Up light on a tree
FX Luminaire PX stainless lighting transformer
Re-check the transformer

Short answer

Match the base first (MR16 bi-pin, G4, PAR36, wedge, or bayonet), then the beam spread, then the color temperature. FX Luminaire rates its 4 W, 5 W, and 6 W MR16 LEDs as replacements for 20 W, 35 W, and 50 W halogen. Keep the transformer load at or under 80% of its rating and check the voltage at each fixture against the lamp’s listed range.

1

Identify the base

Pull one lamp. An MR16 is a 2-inch reflector with two pins. A G4 is a small capsule with two pins. A PAR36 is a 4-1/2 inch sealed beam with screw terminals.

2

Match beam and color

Use the halogen wattage and beam code to pick the LED equivalent. 2700K is warm; 3000K is a little whiter. Use one color temperature across a scene.

3

Re-check the transformer

Add up the lamp VA and stay at or under 80% of the transformer rating. With the system on, confirm the voltage at the fixtures is inside the lamp’s listed range.

Identify the lamp

Which base do you have?

LampHow to spot itUsed in
MR16 (GU5.3 bi-pin)2 in. reflector cup, two thin pinsUp lights, spot lights, well lights
MR11 (GU4 bi-pin)1-3/8 in. reflector cup, two pinsSmall up lights and accent lights
MR81 in. reflector cupCompact accent fixtures
G4 / T3 bi-pinSmall capsule with two straight pins, no reflectorPath, step, and hardscape lights
PAR364-1/2 in. sealed beam with two screw terminalsLarger flood and tree lights
Wedge (T5 / 921, 3156)Flat glass base that pushes straight inPath and step lights
Bayonet (BA15S / BA15D)Round metal base with side pins; S has one contact, D has twoOlder path and area lights

MR and PAR sizes are in eighths of an inch: MR16 is 16/8 = 2 inches across; PAR36 is 36/8 = 4-1/2 inches.

Match the halogen code

Common MR16 halogen codes and an LED starting point

Halogen codeHalogenLED starting point
BAB20 W flood, about 36–38°FX MR16 4 W 35° flood
FMW35 W flood, about 36–38°FX MR16 5 W 35° flood
EXN50 W flood, about 36–38°FX MR16 6 W 35° flood
EXT50 W narrow spot, about 12°Alliance MR16 5 W narrow spot
FNV50 W wide flood, about 60°FX MR16 5 W 60° wide flood

The halogen code is printed on the lamp face or the old box. Watt equivalents follow FX Luminaire’s 20 W / 35 W / 50 W LED ratings.

Lamps we ship

Start with the base you pulled out

These are low-voltage landscape lamps. Check the voltage range on each listing.

Match the symptom

After the swap

What you seeWhat to doStart here
Halogen lamp burned outRead the base and the halogen code, then order the LED equivalent with the same beam.MR16 LEDs · G4 LEDs
LED flickers or shuts offWith the system on, measure the voltage at that fixture and compare it to the lamp’s listed range. Then check the splice.Direct-bury splices
Fixtures look brighter at the end of the runLED load cuts voltage drop. If the run sits on a high tap from the halogen days, move it to a lower tap and re-measure.Transformer calculator
Colors do not match across the yardMixed color temperatures. Pick one (2700K or 3000K) for the scene.LED lamps
Beam looks too tight or too wideMatch the beam code, not just the wattage. Narrow spot for tall trunks, wide flood for walls.Narrow spot · Wide flood
Want to add fixtures after the swapAdd the new lamp VA to the total and stay at or under 80% of the transformer rating.Transformer calculator

The steps people skip

Before you swap every lamp

  1. Turn the transformer off first. Halogen lamps are hot enough to burn; let them cool.
  2. Swap one fixture and look at it at night. Beam and color are easier to judge on one sample than on a box of 20.
  3. Size by VA, not just watts. Lamp listings such as FX Eco show a VA rating. Transformer load is added in VA.
  4. Re-measure voltage after the swap. Less load means less voltage drop. Check the fixtures against the lamp’s listed range.
  5. Check fit in closed fixtures. Some LED lamps are deeper than the halogen they replace. Confirm the lens closes.
  6. Keep the lens gasket. Water in a fixture kills an LED faster than age does.

Common questions

What LED replaces a 20 W, 35 W, or 50 W MR16 halogen?

FX Luminaire rates its 4 W MR16 LED as the 20 W replacement, 5 W as 35 W, and 6 W as 50 W. Match the beam spread of the old lamp as well as the wattage.

Will an LED MR16 fit my halogen fixture?

If the fixture took an MR16, an LED MR16 uses the same 2-inch size and GU5.3 two-pin base. In closed fixtures, check that the LED is not deeper than the halogen so the lens still closes.

Do I need a new transformer for LED landscape lights?

Not usually. 12 V landscape LED lamps run on the same low-voltage landscape transformer. Keep the total load at or under 80% of its rating and confirm the voltage at each fixture is inside the lamp’s listed range.

What color temperature looks like halogen?

2700K is the warm choice most homeowners pick for a halogen-like look. 3000K is slightly whiter. Use one color temperature per scene.

What is the difference between watts and VA on an LED lamp?

Watts is the power the lamp uses. VA (volt-amps) is the load it puts on the transformer, and can be higher than watts on LED lamps. Size the transformer from VA when the listing gives it.

How do I read the beam spread?

Halogen MR16s carry a three-letter code: BAB, FMW, and EXN are 20, 35, and 50 W floods; EXT is a 50 W narrow spot; FNV is a 50 W wide flood. LED listings give the beam in degrees.

Why do my lights look brighter after switching to LED?

LED lamps draw less current, so less voltage is lost along the wire. A run that was moved to a higher tap to make up for halogen drop may now be too high; move it down and re-measure.

Send a photo of the lamp and the fixture

Tell us the code printed on the lamp and the fixture brand. We will match the LED base, beam, and color. Free US shipping.

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