Choosing the wrong voltage for your landscape lighting can waste hundreds of dollars a year, create safety hazards, or leave you with flickering, dim fixtures. Most residential outdoor lighting systems run at either 120 volts (line voltage) or 12 volts (low voltage), and each has real trade-offs you need to understand before installing anything. Get this decision right upfront, and you'll enjoy reliable, efficient lighting that fits your budget and property for years.
Line Voltage vs. Low Voltage: The Core Difference
Line voltage systems operate at standard household current—120 volts in the US. They're the same circuits that power your kitchen outlets and indoor lights. Low voltage systems step down to 12 volts using a transformer, creating a safer, more flexible alternative for outdoor use.
Line voltage offers raw power and longer cable runs (up to 150 feet without voltage drop), making it ideal for large properties or situations where you want to light distant trees or pathways. You'll pay less upfront for fixtures themselves, but installation requires licensed electricians, conduit, and proper permitting—expect $1,500–$3,500 for professional setup on a typical residential lot.
Low voltage is the default for most homeowners. A 12-volt transformer plugs into an outdoor GFCI outlet, then distributes power via low-voltage wiring buried 6–12 inches underground. Fixtures run $15–$80 each, transformers cost $50–$300, and DIY installation is genuinely possible. Total cost for a modest landscape system: $400–$1,200.
Safety Considerations
This matters more than you'd think. Line voltage can deliver a lethal shock if you hit a cable with a shovel or if outdoor wiring fails. That's why it requires conduit, permits, and inspections. You can't easily modify or extend the system yourself without calling a contractor back.
Low voltage is inherently safer. Even if someone touches a 12-volt wire, there's no electrocution risk. Kids and pets around the system aren't in serious danger. You can bury wiring shallowly, splice it yourself if needed, and reroute fixtures without a license.
If safety is your priority—and it should be—low voltage reduces liability and stress, especially on properties where children play or you plan to use the system for decades.
Cost Over Time
Initial installation favors line voltage only on very large properties (over 1 acre with fixtures 100+ feet from the house). For typical residential lots under 0.5 acres, low voltage wins on total cost within the first 3–5 years.
Why the difference:
- Line voltage: Higher upfront ($1,500–$3,500), lower fixture cost, but harder and expensive to expand or repair
- Low voltage: Lower upfront ($400–$1,200), modular expansion, DIY-friendly maintenance, transformer replacement ~$150–$250 every 10–15 years
Energy consumption also matters. Line voltage fixtures often use older halogen or incandescent bulbs (60–150 watts each). Low voltage systems increasingly use LED versions (4–15 watts), cutting power draw by 80–90%. A 12-light low-voltage LED system might cost $10–$15/month to run; a comparable line voltage system could hit $40–$60/month.
Performance and Aesthetics
Line voltage delivers brighter, more dramatic illumination and is often preferred for accent lighting on architectural features or large trees. It's powerful enough to wash an entire facade without multiple fixtures.
Low voltage creates softer, more intimate lighting—think uplighting in planting beds, deck step lights, or pathway markers. Modern LED low-voltage fixtures have improved dramatically in color temperature and brightness (now available in 5,000K cool white or 2,700K warm amber), but they won't match line voltage's punch for long-distance uplighting.
If you're lighting a dramatic stone wall or want theatrical effect, line voltage may be worth the cost. For everyday landscaping that looks attractive and welcoming, low voltage is the smarter choice.
Hiring vs. DIY
Line voltage installation requires a licensed electrician in most jurisdictions. Get 2–3 quotes and verify they're pulling permits. Budget 2–4 weeks for permits and installation.
Low voltage can be DIY-friendly if you're comfortable burying cable and connecting wiring. Many homeowners complete systems in a weekend. If you're unsure, hire a landscape lighting specialist (costs $500–$1,500 for design and install). Platforms like Mercoly let you compare and find trusted outdoor lighting providers in one place, making it easier to request quotes and see reviews.
Frequently Asked Questions
Q: Will low-voltage landscape lights work if I run the transformer on the same outlet my air conditioner uses? No—AC units draw heavy current and will trip the GFCI when the transformer powers on. Always use a dedicated outdoor outlet for your transformer.
Q: Can I run low-voltage cable 200 feet to light a back corner of my property? Not effectively. Standard 12-gauge low-voltage wire causes voltage drop beyond 100–120 feet; lights will dim noticeably. Use 10-gauge wire (adds cost) or install a second transformer closer to distant fixtures.
Q: Do I really need to bury low-voltage wiring, or can I run it on the surface? Burying 6–12 inches prevents tripping hazards and equipment damage, but above-ground wiring works if you plan carefully and use covers on high-traffic paths.
Compare quotes from multiple outdoor lighting contractors to find the right voltage and system for your property.