Maricopa County, AZ Outdoor Lighting: Dark Sky Rules (2026)
Key Facts
- Governing rule
- MCZO § 812, Outdoor Light Control Provisions
- Unshielded illumination
- Prohibited on buildings, landscaping, signs
- Exception
- Incandescent under 150 watts, or low-pressure sodium
- Mercury vapor luminaires
- New installations prohibited
- Advertising searchlights
- Banned 11 p.m. to sunrise
Summary
In unincorporated Maricopa County, most exterior lighting must be fully or partially shielded to control glare and light trespass, and unshielded building, landscape, or sign lighting is banned except for small incandescent or low-pressure sodium fixtures.
The unshielded outdoor illumination of any building, landscaping, signing or other purpose is prohibited, except with incandescent fixtures of 150 Watts or less, or low pressure sodium luminaires.
Full Breakdown
Maricopa County Zoning Ordinance Section 812 governs outdoor lighting on unincorporated land to curb light pollution that affects nighttime astronomical observations. Exterior fixtures for buildings, parking lots, landscaping, recreational facilities, and signs must be shielded according to luminaire type: high-pressure sodium, metal halide, quartz, and incandescent fixtures over 150 watts require full shielding that keeps light rays below the horizontal plane at the fixture. Unshielded illumination of buildings, landscaping, or signs is banned outright except for incandescent lamps under 150 watts or low-pressure sodium lights, and installing new mercury-vapor luminaires is prohibited entirely. Advertising searchlights are barred between 11 p.m. and sunrise.
Violations & Fines
Non-compliant outdoor lighting is a zoning violation and public nuisance under MCZO Chapter 12: each day it continues is a separate class 2 misdemeanor, with civil penalties capped at the maximum misdemeanor fine under A.R.S. § 11-815(D).
Frequently Asked Questions
Does Maricopa County require shielded outdoor lights?
Can I install mercury-vapor lights outdoors in unincorporated Maricopa County?
Does this outdoor lighting rule apply inside Phoenix or Scottsdale?
Sources & Official References
Other rules in Maricopa County
Compare Maricopa County to another location·View the Arizona outdoor lighting overview
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