Noise ordinances › Montgomery County, MD

Montgomery County noise ordinance: quiet hours, limits and complaints

Last updated: November 4, 2026

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Quiet hours in Montgomery County

Chapter 31B sets a day and night clock rather than one quiet-hours ban. Nighttime is 9 p.m. to 7 a.m. on weekdays and 9 p.m. to 9 a.m. on weekends and holidays; daytime is 7 a.m. to 9 p.m. on weekdays and 9 a.m. to 9 p.m. on weekends and holidays (Sec. 31B-2). At night the limit falls from 65 to 55 dBA in a residential noise area and from 67 to 62 dBA in a non-residential noise area (Sec. 31B-5(a)). The noise disturbance ban (Sec. 31B-5(b)) names no hours, so it applies day and night. The County's Noise Control page says it is unlawful to create a noise disturbance anywhere during quiet hours and that the nuisance provision prohibits some noise disturbances at any time; the code has no such split, and the code controls. Construction has its own clock: the higher construction levels apply only from 7 a.m. to 5 p.m. on weekdays, and at all other times, weekends included, the ordinary Sec. 31B-5 levels apply (Sec. 31B-6(a)(1)). The code's examples of construction noise that violates the chapter, if it exceeds the limits or creates a noise disturbance, include delivering materials or loading during nighttime hours in a residential noise area and running construction equipment with audible back-up alarms during nighttime hours (Sec. 31B-6(c)). At a qualifying performing arts facility (County owned or operated, and designated by the County Executive) the outdoor limit is 75 dBA from 11 a.m. to 11 p.m., April 1 through October 31 (Sec. 31B-6A). Sound that is not electronically amplified, from sports, amusements, entertainment events or other public gatherings operating under the required permit or license, is exempt from 7 a.m. to 11 p.m. (Sec. 31B-10(a)(4)). Maryland's state standard keeps a different clock, with daytime hours of 7 a.m. to 10 p.m. and nighttime hours of 10 p.m. to 7 a.m. (COMAR 26.02.03.01), so the County's night starts one hour earlier and, on weekends and holidays, ends two hours later.

Decibel limits

Sec. 31B-5(a) sets maximum allowable noise levels in dBA (decibels on the A-weighting scale of a sound level meter) by the kind of area receiving the sound: 65 dBA daytime and 55 dBA nighttime in a residential noise area, and 67 dBA daytime and 62 dBA nighttime in a non-residential noise area. Which area applies turns on zoning (Sec. 31B-2). Sound that crosses between residential and non-residential noise areas must meet the residential levels (Sec. 31B-5(a)(3)). A prominent discrete tone (a whine or hum heard as a single pitch) or impulsive noise (a short burst, such as weapons fire or a pile driver) must stay 5 dBA below the table, at the location on a receiving property where noise from the source is greatest (Sec. 31B-5(a)(2)). Construction may reach 75 dBA from 7 a.m. to 5 p.m. on weekdays, or 85 dBA if the Department of Environmental Protection (DEP) has approved a noise-suppression plan, measured at the location, at least 50 feet from the source, on a receiving property where noise from the source is greatest; at all other times the Sec. 31B-5 levels apply (Sec. 31B-6(a)). Outdoor arts and entertainment at a qualifying performing arts facility may reach 75 dBA, measured on the receiving property, from 11 a.m. to 11 p.m., April 1 through October 31, and the Sec. 31B-5 levels at all other times (Sec. 31B-6A). A leaf blower may not have an average sound level exceeding 70 dBA at a distance of 50 feet (Sec. 31B-9(a)), and combustion engine-powered handheld, backpack and walk-behind leaf blowers and leaf vacuums are banned whatever their level (Sec. 31B-9(e), (f)). The County Executive may set stricter limits for a designated noise sensitive area (Sec. 31B-8); the text we read does not list any. The County's complaint page says the limits are for external noise measured outside at the property line and that the law has no specific sound limits for internal noise. A noise disturbance needs no decibel reading: the County says those criteria depend on the observations and testimony of witnesses or a code enforcement officer. Maryland's state standard, COMAR 26.02.03.02 Table 1, uses the same numbers for residential land (65 and 55) and commercial land (67 and 62), adds 75 dBA day and night for industrial land, allows construction 90 dBA in daytime hours, and caps air conditioners at 70 dBA and heat pumps at 75 dBA at receiving residential property. Chapter 31B does not cite COMAR; it says only that the chapter does not apply to a source expressly subject to a state or federal noise law that is more stringent (Sec. 31B-10(a)(3)). Since October 1, 2012 the Maryland Department of the Environment is no longer responsible for noise enforcement: it sets statewide standards and redirects local complaints to local contacts.

What the ordinance actually says

Sec. 31B-5(b): "Noise disturbance. A person must not cause or permit noise that creates a noise disturbance."

Sec. 31B-2: "Noise disturbance means any noise that is: (1) unpleasant, annoying, offensive, loud, or obnoxious; (2) unusual for the time of day or location where it is produced or heard; or (3) detrimental to the health, comfort, or safety of any individual or to the reasonable enjoyment of property or the lawful conduct of business because of the loudness, duration, or character of the noise."

Sec. 31B-2: "Nighttime means the hours from 9 p.m. to 7 a.m. weekdays and 9 p.m. to 9 a.m. weekends and holidays."

Sec. 31B-5(a)(2): "A person must not cause or permit the emission of a prominent discrete tone or impulsive noise that exceeds a level, at the location on a receiving property where noise from the source is greatest, that is 5 dBA lower than the level set in paragraph (1) for the applicable noise area and time."

Sec. 31B-6(a)(1): "A person must not cause or permit noise levels from construction activity that exceed the following levels: (A) From 7 a.m. to 5 p.m. weekdays: (i) 75 dBA if the Department has not approved a noise-suppression plan for the activity; or (ii) 85 dBA if the Department has approved a noise-suppression plan for the activity. (B) The level specified in Section 31B-5 at all other times."

Sec. 31B-12(b): "A violation of this Chapter is a Class A violation. Each day a violation continues is a separate offense."

Sec. 31B-12(f): "Except as provided in Section 31B-9(j), an enforcement officer may issue a civil citation for any violation of this Chapter if the enforcement officer: (1) witnesses the violation; or (2) receives complaints from at least 2 witnesses of a noise disturbance."

Sec. 31B-9(f): "A person must not use a combustion engine-powered handheld, backpack, or walk-behind leaf blower or leaf vacuum."

Sec. 31B-9(j): "An enforcement officer may issue a civil citation under this Section if: (1) the Director receives a complaint from at least one witness of a noise disturbance in violation of subsection (f); and (2) the complaint was received by the Director within 7 days of the alleged violation."

Sec. 31B-1(b)(2): "A County agency, municipality in which this Chapter applies, or regional authority subject to County law must not adopt a standard or regulation that is less stringent than this Chapter or any regulation adopted under this Chapter."

Sec. 5-203(a)(6): an owner must not "Allow an animal to cause noise that is loud and persistent enough to disturb another person's quiet enjoyment."

Rockville City Code Sec. 1-8(b)(21), Ordinance No. 15-25: "Chapter 31B (noise control), except that this chapter shall not apply to refuse collection performed by the City;"

COMAR 26.02.03.02 B(1): "A person may not cause or permit noise levels which exceed those specified in this table except as provided in §B(2) or (3), or §C, of this regulation."

Quoted verbatim from the official text (Montgomery County Code Chapter 31B, with COMAR 26.02.03 and related County provisions. Montgomery County Code on American Legal, version 2026 S-92 (current): Chapter 31B (Noise Control), Secs. 31B-1 to 31B-12 (1996 L.M.C., ch. 32, § 1; Sec. 31B-5 last amended by 2011 L.M.C., ch. 7, § 1; Secs. 31B-9, 31B-10 and 31B-12 amended by 2023 L.M.C., ch. 31, § 1, which is Bill 18-22, effective January 8, 2024; Secs. 31B-2, 31B-9 and 31B-12 last amended by 2025 L.M.C., ch. 28, § 1, which is Expedited Bill 30-25, effective December 1, 2025); Sec. 1-19 (fines and penalties); Sec. 5-203 (animal noise) and Sec. 5-301; Sec. 31-9E (Vehicle Noise Abatement Monitoring Pilot Program). Code of Montgomery County Regulations (COMCOR) Chapter 31B, of which only the definitions in COMCOR 31B.00.01 were read. State law: Code of Maryland Regulations (COMAR) 26.02.03.01 (definitions) and 26.02.03.02 (Environmental Noise Standards), read on regs.maryland.gov. Rockville City Code Sec. 1-8, as amended by Ordinance No. 15-25, effective January 1, 2026. Takoma Park City Code Chapter 14.12 (Noise Control), as amended through Ord. 2026-3, 2/25/2026, on eCode360. Text read 2026-11-04.). Verified against the live code on 2026-11-04. Ordinances get amended — before acting on a specific provision, check the linked official code. This page is a plain-language summary, not legal advice.

How to file a noise complaint in Montgomery County

For noise happening now, or any noise complaint after business hours or on a weekend, call the Montgomery County Police non-emergency line, 301-279-8000, which the County lists as available 24/7 for a noise complaint, and use 911 only for emergencies. During business hours, contact MC311 (311 in the County, 240-777-0311 from outside it, Monday to Friday 7 a.m. to 7 p.m., closed weekends and holidays; MC311.com is open 24/7) or file the Department of Environmental Protection's (DEP) online noise complaint; MC311 says a DEP investigator will typically contact you within 3 business days. The County's page also sends noise disturbances from trash collection during quiet hours to MC311. For a noise disturbance no enforcement officer witnessed, two people can file the Citizen's Two Party Noise Disturbance Complaint online, because an officer may issue a civil citation on complaints from at least 2 witnesses (Sec. 31B-12(f)(2)). Both signers must be over 18, each event needs its own form, testimony will be required if the case is heard in District Court, and a copy of the form with your contact information goes to the alleged violator if there is enough evidence for a citation. For a gas-powered leaf blower, one witness is enough if the Director of DEP receives the complaint within 7 days of the violation (Sec. 31B-9(j)). For a barking dog or other animal, call 301-279-8000 and press 2 for the Office of Animal Services, or 240-314-8930 if the incident is in the City of Rockville; MC311 says a violation of Sec. 5-203(a)(6) may result in a $100 fine. For vehicle noise, call the police line, since the County says motor vehicles are regulated under the State Motor Vehicle Code by the Police and not under its noise law. For routine sounds between apartments, the County says the building manager or property management company is responsible, and the Office of Landlord-Tenant Affairs (240-777-0311) can help with questions. In Takoma Park, which exempts itself from Chapter 31B, use the City's Code Enforcement staff (301-891-7113 or 301-891-7243). Penalties: a violation of Chapter 31B is a Class A violation and each day it continues is a separate offense (Sec. 31B-12(b)). Under Sec. 1-19 that means, as a misdemeanor, a fine of up to $1,000, up to 6 months in jail, or both; or, as a civil violation, $500 for an initial offense and $750 for a repeat offense, unless an executive regulation sets a lower amount. Sources: https://www.montgomerycountymd.gov/propertycare/noise-control, https://www.montgomerycountymd.gov/propertycare/noise-control/file-noise-complaint, https://www.montgomerycountymd.gov/office-public-information/make-right-call, https://www3.montgomerycountymd.gov/311/SolutionView.aspx?SolutionId=1-8RQ28P, https://www3.montgomerycountymd.gov/311/SolutionView.aspx?SolutionId=1-2HK5AY, https://www2.montgomerycountymd.gov/DepCaseSurvey/NoiseComplaint.aspx, https://takomaparkmd.gov/314/Noise-Control and https://ecode360.com/47262041.

Step by step, with what to log and what to expect after you file: how to file a noise complaint in Montgomery County. For the general playbook — documenting the problem, talking to a landlord or HOA, when 311 beats 911 — see the noise complaints guide.

Worth knowing

(1) Where the law applies: Chapter 31B is County law run by the Department of Environmental Protection (DEP) and is not limited to unincorporated areas: its definitions reach land zoned by a political subdivision where the County's zoning chapter does not apply, and a person authorized by a municipality may enforce it (Sec. 31B-2). But it also speaks of a "municipality in which this Chapter applies" (Sec. 31B-1(b)(2)), so it does not assume it reaches every town. Takoma Park exempts itself from Chapter 31B "except as expressly set forth in this chapter" (City Code § 14.12.020), so its own Chapter 14.12 applies there: 65 dBA by day and 60 dBA at night, on a different clock, with nighttime from 8 p.m. to 7 a.m. on weekdays and 10 p.m. to 9 a.m. on weekends and holidays (§§ 14.12.030, 14.12.050). A two-party complaint there needs two City residents at separate addresses and must reach City Code Enforcement within 10 days (§ 14.12.130E). The City's chapter keeps two ties to the County: DEP has concurrent authority with City officers over construction noise levels and noise-suppression plans (§ 14.12.060D), and County measurement regulations apply if the City has adopted none (§ 14.12.040B). Rockville's code lists Chapter 31B among the County laws that apply in the city until the City exempts itself, except for refuse collection performed by the City (Rockville City Code Sec. 1-8(b)(21)). We could not confirm how Chapter 31B applies in Gaithersburg and did not check the County's other municipalities, so ask the city or MC311 first. Washington, D.C. is a separate jurisdiction (see the Washington page); this page's map link goes there because the County's own places are not in our noise map. (2) Two tests: a person can break the law with a measured level over the limit or with a noise disturbance, and a disturbance needs no reading (Sec. 31B-5(a), (b)). It covers noise that is unpleasant, annoying or loud, or simply unusual for the time of day or location (Sec. 31B-2). (3) Citations: an officer must witness the violation or receive complaints from at least 2 witnesses of a noise disturbance. The 2 witnesses are needed to issue the citation under that route, not to prove the violation (Sec. 31B-12(f)). (4) Apartments and condos: the County says its law has no specific sound limits for noise between units, and that loud voices, footsteps, slamming doors and similar routine sounds are for the building manager. The code's definition of receiving property does include an apartment, condominium unit or cooperative building unit (Sec. 31B-2), and the County's page says the noise disturbance rule reaches multi-family buildings and townhouses. (5) Page and code differ on what is covered: the County's complaint page says the law does not cover aircraft, railroads or motor vehicles on public roadways. Sec. 31B-10 names none of these; it exempts a source expressly subject to a more stringent state or federal noise law. An editor's note in the code cites a 1992 County Attorney opinion that the Washington Metropolitan Area Transportation Authority, especially Metrorail, is subject to the County's noise law, although an exemption may be obtained if it is in the public interest. Where the page and the code differ, the code controls. (6) Written exemptions (Sec. 31B-10): agricultural field machinery used and maintained to the manufacturer's specifications, emergency operations by fire and rescue services, police or public utilities and their contractors, and non-amplified event sound from 7 a.m. to 11 p.m. The County Executive may by regulation exempt routine daytime residential sources such as home workshops, power tools and lawn and garden equipment from Sec. 31B-5 (Sec. 31B-10(b)); we did not read a regulation doing so. (7) Leaf blowers: the sale ban took effect July 1, 2024 and the use ban July 1, 2025 (Bill 18-22). Expedited Bill 30-25 removed the photo requirement on December 1, 2025, so a single witness complaint within 7 days can support a citation (Sec. 31B-9(j)). Agricultural producers on agriculturally assessed property are exempt from Sec. 31B-9 (Sec. 31B-10(c)). (8) Construction: the person responsible and the site manager can each be held liable for a violation, and recurring violations can bring a stop work order of up to 3, then 5, then 7 working days (Sec. 31B-12(i)). (9) Waivers: the Director may waive the chapter for a temporary event for no more than 30 days, renewable no more than twice, after public notice, or for up to 3 years after a hearing if compliance is not practical and would impose undue hardship (Sec. 31B-11). (10) Animals are covered twice: allowing an animal to create a noise disturbance is a Chapter 31B example (Sec. 31B-5(c)(6)), and Sec. 5-203(a)(6) separately bans animal noise loud and persistent enough to disturb another person's quiet enjoyment. Repeating it after notice from the County is a public nuisance (Sec. 5-203(b)(1)), and the Executive Director of the Office of Animal Services may go to the Animal Matters Hearing Board instead of issuing a citation (Sec. 31B-12(g)). (11) Suing a neighbor: Sec. 31B-12(j) says any person aggrieved by a violation may file a civil action after notifying the alleged violator and the Director at least 60 days before, unless the County Attorney has already sued over the same violation. An editor's note says that in Burrows v. United States (2004) a court read Chapter 31B as allowing neither a private cause of action for noise control nor a suit against the federal government. The code does not explain how the two fit. (12) Vehicle noise cameras: Sec. 31-9E set up a police pilot of 3 noise monitoring systems, with a warning for a first offense and a civil penalty of up to $75 after that. The editor's note says that Act must sunset at the end of June 30, 2026, a date now past; the section still appeared in the code when read, and we did not confirm whether the program continues. (13) State role: Maryland's list of local noise contacts names the County Executive at 240-777-2500, but the County's own pages send complaints to the police line and MC311.

Document it before you report it

Some of Montgomery County's limits are measured numbers, so a reading can help, and a dated log counts either way. Take a quick reading with the free online decibel meter — it runs in your browser and records nothing — and see the nearest city we map, on the Washington noise map. For time-stamped measurement history you can show a landlord or code officer, the app keeps a log.