Low Voltage Landscape Lighting and Transformer Sizing
Most home landscape lighting runs at 12 volts from a transformer; load the transformer to about 70% of its rating, and compare fixtures by lumens, not watts.
By Amanda RoseContributing writer.
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The short answer
Landscape lights come in two electrical systems. Line voltage runs at the household 120 volts in the U.S.; low voltage runs at 12 volts through a transformer that plugs into or wires to the house supply. Volt Lighting, which sells both, calls 12 volt the most common choice for homes and keeps 120 volt mainly for commercial, security and very large areas. Size the transformer from the total watts of your fixtures, leaving headroom, and judge brightness by lumens.
Low voltage vs line voltage landscape lighting
| Low voltage (12 V) | Line voltage (120 V) | |
|---|---|---|
| Shock risk | Lower; suits wet areas and yards where children and pets play | Higher; every connection must be waterproof |
| Cable | Does not need deep burial or conduit | Buried 18 inches deep or run in conduit, with sealed junction boxes |
| Installer | Does not need a licensed electrician | Needs a licensed electrician |
| Fixtures | More choice, easy to move | Larger fixtures, fewer options |
| Typical use | Homes, paths, gardens | Commercial and security lighting, lighting large trees or areas |
That summary follows Volt Lighting's comparison. Check your local electrical code before you dig, since rules vary by place. Long cable runs were once an argument for line voltage, but Volt says modern LEDs and multi-tap transformers usually handle voltage drop on 12 volt systems unless the runs are very long.
What size transformer for landscape lighting?
Add up the wattage of every fixture you plan to run from the transformer, then pick a transformer with room to spare. Volt explains the headroom in its transformer guide:
- The National Electrical Code allows a circuit to be loaded to only 80% of its maximum.
- Losses in the cable take roughly another 10%.
- So plan to use about 70% of the transformer's rating.
For a 300 watt transformer, that means about 210 watts of fixtures. If your total is higher, step up a size: Volt's guide notes the same steps apply to its 600, 900 and 1,200 watt models. Leaving spare capacity also lets you add lights later.
How many lumens for landscape lighting?
Lumens measure how much light comes out; watts measure power used. With LEDs, watts say little about brightness. Volt's conversion chart, for example, puts an 800 lumen output at 60 watts for incandescent but 9 watts for LED, and gives LED efficacy as typically 75 to 110 lumens per watt.
When comparing fixtures, look for fixture lumens, the light that actually leaves the fixture. A lamp's own lumen rating applies to the bare bulb, and Volt warns that some makers quote lamp lumens without saying so.
What Wiki Shopping lists
Of the 97 landscape lights listed in patio, lawn and garden on Wiki Shopping on October 26, 2026, the ones that state a type break down as 41 path lights, 24 deck lights, 12 spotlights, 11 figurine lights, 5 in-ground lights and 4 step lights. Many are sold in sets: 27 listings are 2-packs and 19 are 4-packs.
How we count
Type and pack size are read from each landscape light's store listing. Lights that do not state them are left out of those counts. The counts change as listings are added or removed.