Montgomery County, MD Outdoor Lighting: Dark Sky Rules (2026)
Key Facts
- Fixture type
- Full or partial cutoff required
- Illumination cap
- 0.5 footcandles at lot line
- Field lighting curfew
- 11 p.m.-7 a.m. ban
- Enforcing agency
- Dept. of Permitting Services
- Exempt municipalities
- Rockville, Gaithersburg, Poolesville, 4 others
Summary
Montgomery County's zoning ordinance requires every new or replaced outdoor lighting fixture to be a full or partial cutoff type that directs light downward, capping on-site illumination at 0.5 footcandles at the lot line.
1. Fixture (Luminaire) To direct light downward and minimize the amount of light spill, any outdoor lighting fixture must be a full or partial cutoff fixture. ... D. Excessive Illumination Except where otherwise stated in this Chapter, on-site illumination must be 0.5 footcandles or less at the lot line, excluding street lights within the right-of-way.
Official source re-checked September 7, 2026: no newer edition of the code had been published (publisher’s edition: 2026 S-90: Montgomery County Code contains legislation effective through May 7, 2026 | Zoning Updated Effective: April 13, 2026 | COMCOR Regulations effective as of July 1, 2026).
Full Breakdown
Montgomery County's Zoning Ordinance (Chapter 59) requires any new or replaced outdoor lighting fixture to be a full or partial cutoff fixture that directs light downward and minimizes spill, under Section 6.4.4.B.1. On-site illumination generally can't exceed 0.5 footcandles at the lot line, security fixtures can't project above a building's roofline or face ground-floor residential uses, and lighting for outdoor playing fields is prohibited between 11:00 p.m. and 7:00 a.m. absent approval of other hours. The Department of Permitting Services reviews compliance through site plan and building permit review. Chapter 59 does not apply inside Rockville, Gaithersburg, Poolesville, Brookeville, Laytonsville, Barnesville, or Washington Grove, which set their own outdoor lighting standards.
Violations & Fines
Fixtures that fail the cutoff or footcandle standards get flagged during DPS site plan or building permit review, and noncompliant lighting must be corrected before permit or occupancy approval issues.
Frequently Asked Questions
Does this rule apply inside Rockville or Gaithersburg?
Can I point landscape lighting upward?
Sources & Official References
Other rules in Montgomery County
Compare Montgomery County to another location·View the Maryland outdoor lighting overview
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