Bolthole Index

St. Mary's County, Maryland

Building permits, zoning and septic in Town of Leonardtown, Maryland

Town of Leonardtown, Maryland requires a building permit before erecting a building or addition inside town limits.1 Leonardtown controls its own zoning in St. Mary's County; the Town Planning and Zoning Commission approves new houses.23 Private septic construction, expansion and repair applications go to St. Mary's County Health Department Environmental Health Division.4

At a glance

Building permit
Required before erecting a building or addition1
Zoning
Town zoning applies inside town limits2
Building inspections
Footers and foundations, framing, insulation and final5
Private septic
County Health Department Environmental Health Division4
R-SF setbacks
Front and rear: 25 feet; each side: 8 feet; combined sides: 18 feet6
Private well
Maryland well construction permit required7

Who to call

Building permits

Town of Leonardtown Office of Planning and Zoning

Town building and zoning questions; Planning and Zoning Commission approval for new houses and commercial developments

(301) 475-9791

[email protected]

22670 Washington Street, Leonardtown, MD 20650

Septic permits

St. Mary's County Health Department, Environmental Health Division

Private septic construction, expansion, repairs and inspections

(301) 475-4321

[email protected]

21580 Peabody St. Leonardtown, MD 20650

Contact details are copied from each office’s official page and were checked against it on October 12, 2026.

Off-grid gear

Going off-grid in Town of Leonardtown means bringing your own water and power. The kit we’d start with:

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Do you need a building permit in Town of Leonardtown, MD?

Leonardtown requires a written application and an issued building permit before construction of a building or addition begins inside corporate limits.1 The application must describe the proposed location, size, construction materials and intended use.1 Leonardtown has adopted the Maryland Building Performance Standards and listed ICC codes subject to Town provisions and amendments accepted by the Town Zoning Administrator.8 We could not confirm an owner-builder exemption inside Leonardtown; ask the Town Office of Planning and Zoning whether your proposed work qualifies for any exemption.13

Who handles building approval in Town of Leonardtown?

Start a Leonardtown home project with the Town Office of Planning and Zoning, reached through the town contact listed below.53 The Leonardtown Planning and Zoning Commission has approval authority for new houses and commercial developments.3 Building inspections are initially arranged through the Town Office of Planning and Zoning using an independent inspecting agency under contract.5 Required minimum inspections cover footers and foundations, framing, insulation and final work, with a fee for each inspection under the Town user-fee schedule.5 Ask the town office for the current application materials, inspection scheduling instructions and fee schedule before submitting your project.3

Does Town of Leonardtown have zoning and setback rules?

Leonardtown has its own zoning ordinance for land inside town limits.2 In the R-SF Single-Family Residential District, required yards are at least 25 feet deep at the front and rear, with each side at least 8 feet wide and both sides totaling at least 18 feet.6 Those R-SF standards apply to permitted and special-exception uses, structures and buildings in that district.6 Use the R-SF figures only for an R-SF parcel; ask the Town Office of Planning and Zoning to identify the parcel's district and applicable dimensional standards.63 We could not confirm Leonardtown's minimum dwelling size, lot coverage or building-height limits; request those standards from the town office before choosing a house plan.3

How do private septic permits work in Town of Leonardtown?

For a Leonardtown property proposed to use private septic, St. Mary's County Health Department Environmental Health Division administers countywide individual septic construction, expansion and repair applications.4 New construction or repair requires perc testing, and new construction requires a site plan prepared by a Maryland-registered land surveyor.9 Septic construction may begin after approval of the septic construction application, and the approved permit lasts 2 years from issuance.9 Contact Environmental Health for the inspection before covering the installed system.10 Ask the town office whether the specific parcel must use public sewer before pursuing a private-system design.3

Can you live in an RV or tiny home in Town of Leonardtown?

We could not confirm permission to occupy an RV or tiny home on a private Leonardtown parcel; ask the Town Office of Planning and Zoning about the proposed structure, residential use and duration before relying on either as housing.23 A building or addition inside Leonardtown still requires a building permit before construction starts.1 Maryland protects qualifying new manufactured homes and modular dwellings in zones allowing single-family residential uses, subject to applicable local codes and requirements.11 That protection requires qualifying manufactured homes to be attached to a permanent foundation and converted to real property; it does not require towns to allow mobile homes on wheels or temporary foundations.11

Building a home in Town of Leonardtown: what comes first?

  1. Ask Town Planning and Zoning to confirm the zoning district and proposed use; the Town Commission approves new houses.23
  2. Resolve the wastewater plan; private septic construction requires Health Department approval and new construction requires a surveyed site plan.9
  3. Submit the written building application describing location, size, materials and use, and receive the building permit before construction.1
  4. Arrange the required building inspections through the Town Office of Planning and Zoning.5
  5. Complete Town-approved driveway paving where a new residential structure has driveway, turn-around or parking access from a public street; a permanent certificate of occupancy is withheld until compliant paving is complete.1213

What should you check before buying in Town of Leonardtown?

Leonardtown development in regulated flood hazard areas is subject to the Town's floodplain permit, review and inspection requirements; ask Town Planning and Zoning about the parcel's floodplain status.143 A private well requires a Maryland well construction permit, and a potable well on property already connected to a community water supply needs Department authorization.7 Leonardtown also regulates subdivision of land wholly or partly inside town limits, generally requiring a recorded plat when a parcel is transferred from a larger tract.15 The agricultural land-division exclusion applies to bona fide agricultural divisions not for development and does not provide a general building or zoning exemption.16 For land outside town limits, use the St. Mary's County guide for the county's unincorporated-area subdivision requirements.17

Watch-outs

  • Leonardtown's R-SF setbacks are district-specific; do not apply them to every town parcel.6
  • Budget for approved driveway paving before a permanent certificate of occupancy for new residential structures with access from a public street.13
  • We could not confirm an owner-builder exemption or private-parcel RV occupancy permission in Leonardtown; ask Town Planning and Zoning before buying for either plan.123

Sources

  1. Chapter 48 Building Construction - Town of Leonardtown (Town of Leonardtown), quoted and re-checked
  2. Chapter 155 Zoning - Town of Leonardtown (Town of Leonardtown), quoted and re-checked
  3. Town of Leonardtown Office of Planning and Zoning (leonardtownmd.gov)
  4. On-Site Septic Systems, quoted and re-checked
  5. Chapter 48 Building Construction - Town of Leonardtown (Town of Leonardtown), quoted and re-checked
  6. Article II: R-SF Single-Family Residential District (Town of Leonardtown), quoted and re-checked
  7. Well Construction Permit Applications and Forms (Maryland statewide rule), quoted and re-checked
  8. Chapter 48 Building Construction - Town of Leonardtown (Town of Leonardtown), quoted and re-checked
  9. On-Site Septic Systems, quoted and re-checked
  10. On-Site Septic Systems, quoted and re-checked
  11. mgaleg.maryland.gov (Maryland statewide rule), quoted and re-checked
  12. Article II: R-SF Single-Family Residential District (Town of Leonardtown), quoted and re-checked
  13. Article II: R-SF Single-Family Residential District (Town of Leonardtown), quoted and re-checked
  14. Chapter 78 Floodplain Management - Town of Leonardtown (Town of Leonardtown), quoted and re-checked
  15. Chapter 131 Subdivision Regulations - Town of Leonardtown (Town of Leonardtown), quoted and re-checked
  16. Chapter 131 Subdivision Regulations - Town of Leonardtown (Town of Leonardtown), quoted and re-checked
  17. St. Mary's County Subdivision Ordinance, quoted and re-checked

Written October 12, 2026 from the rules quoted below, each taken from an official source and re-checked by an independent reviewer. This is research, not legal advice: rules change, so confirm with the office before you buy or build.

Answers from the rulebook for Town of Leonardtown

Town of Leonardtown’s own rules

  • Building permitRequired

    Erection of any building or addition within Leonardtown's corporate limits.

    • A written application must state proposed location, size, construction materials and intended use.
    • The permit must be received before construction begins.
    “without first making an application and receiving a permit”
  • Building code adoptedAdopted

    Construction, modification and repair of buildings and structures inside Leonardtown town limits.

    • Maryland Building Performance Standards and the listed ICC codes are adopted subject to Town provisions and Appendix A.
    • Subsequent amendments are adopted upon review and acceptance by the Town Zoning Administrator.
    • Town Code controls over conflicting Maryland Building Performance Standards provisions.
    “adopted as the Building Code of Leonardtown, Maryland”
  • InspectionsRequired

    All buildings and structures governed by the Leonardtown Building Code.

    • Minimum inspections are footers and foundations, framing, insulation and final.
    • Inspections are initially arranged through the Leonardtown Office of Planning and Zoning by contract with an independent inspecting agency.
    • A fee for each inspection is due under the Town user-fee schedule.
    “The following minimum inspections shall be required”
  • Certificate of occupancyLimited

    New single-family, two-family or multifamily residential structures with driveway, turn-around or parking-area ingress or egress from a public street.

    • A permanent certificate of occupancy will not be issued until a compliant paved driveway is constructed.
    • Acceptable paving materials include concrete, hot mix asphalt, pervious pavers or another Town-approved material.
    “A permanent certificate of occupancy will not be issued”
  • Local zoningPresent

    Land inside Leonardtown town limits; Chapter 155 is the Town's zoning ordinance.

    • The zoning chapter was adopted by the Mayor and Council of Leonardtown on 8-12-2002 by Ordinance No. 107.
    “Adopted by the Mayor and Council of the Town of Leonardtown 8-12-2002 by Ord. No. 107.”
  • Agricultural exemptionConditional

    Agricultural land division under Leonardtown subdivision regulations.

    • The subdivision definition excludes a bona fide division or partition of agricultural land not for development purposes.
    • This is an exemption from the chapter's subdivision definition, not a general exemption from all building, zoning, utility or health requirements.
    “shall not include a bona fide division or partition of agriculture land not for development purposes”
  • Subdividing landRegulated (with conditions)

    Subdivision of land wholly or partly within Leonardtown town limits.

    • A plat must be made and recorded before or at the time of sale, exchange or purchase of a parcel from a larger tract.
    • The chapter excludes bona fide division or partition of agricultural land not for development purposes.
    • The regulations do not apply to subdivisions created and recorded before the chapter's effective date.
    “No person shall subdivide any tract of land”
  • Driveway accessRequired

    New single-family, two-family and multifamily residential structures with driveway, turn-around or parking-area access to a public street.

    • The access area must be paved before a permanent certificate of occupancy is issued.
    • Town-approved paving materials are required.
    “All new single-family, two-family or multifamily residential structures with driveways, turn-arounds or parking areas with ingress or egress off of a public street must be paved.”
  • Building in a floodplainRequired

    Development in Leonardtown flood hazard areas.

    • Chapter 78 establishes floodplain administration, permits, application review, inspections and requirements for flood hazard areas.
    • Parcel-specific applicability depends on whether the property lies in a regulated flood hazard area.
    “§ 78-14 Permits required and expiration.”

Rules another office applies inside Town of Leonardtown

Town of Leonardtown does not set these itself; the county, a health district or the state does, and they apply to every address inside its limits.

  • SetbacksSpecified

    R-SF Single-Family Residential District inside Leonardtown town limits.

    • The front, side and rear yard standards apply to uses, structures and buildings listed as permitted or special exceptions in the R-SF District.

    minimum front-yard depth: >= 25 feet · minimum each side-yard width: >= 8 feet · minimum aggregate side-yard width: >= 18 feet · minimum rear-yard depth: >= 25 feet

    “The front yard shall have a minimum depth of 25 feet, a minimum width of each of two side yards of eight feet, and a total aggregate width of 18 feet for both side yards, and a minimum depth of rear yard of 25 feet.”

Still unanswered

We looked and could not find an official answer yet. Silence is not permission; ask Town of Leonardtown or St. Mary's County directly.

  • Owner-builder exemption — Owner-builders constructing inside Leonardtown town limits.
  • Minimum dwelling size — Minimum dwelling size in Leonardtown residential districts.
  • Lot coverage — Lot coverage inside Leonardtown town limits.
  • Building height — Building height inside Leonardtown town limits.
  • Tiny homes — Tiny-home occupancy inside Leonardtown town limits.
5 more unanswered
  • Who permits septic
  • Septic permit
  • Septic inspection
  • Off-grid sanitation
  • Well permit

Each answer was extracted from an official source and independently re-checked against that source by a second reviewer. That is an evidence check, not legal advice. Rules change; confirm with the authority before you buy or build.

Unanswered questions are usually a sign that Town of Leonardtown publishes no rule on the point, not that none exists. St. Mary's County’s page lists the county offices to call.

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