Bolthole Index

Hidalgo County, Texas

Zoning, building permits and septic rules in Mercedes, Texas

Mercedes, Texas has its own zoning ordinance, so every lot inside city limits sits in a mapped district1. The city's code says no new on-site sewage facilities will be allowed inside Mercedes2. Building permits are handled through the City of Mercedes, not Hidalgo County's planning counter3.

At a glance

Zoning
Yes, the city zones; land must conform to its mapped district1
Zoning districts
Sixteen categories4
Building permits
Issued by the City of Mercedes; fees follow the city fee schedule53
Septic
No new on-site sewage facilities inside city limits2
Single-family front yard (Class A)
At least 40 feet, unless an established building line controls6
Height (Class A)
No more than 40 feet7

Who to call

Building permits

City of Mercedes (City Hall)

Main contact for building permits, zoning and code compliance inside Mercedes city limits

956-565-3114

[email protected]

400 South Ohio Avenue

Planning & zoning

City of Mercedes Planning and Development (zoning and rezoning)

Zoning districts and rezoning requests inside Mercedes

956-565-3114

[email protected]

400 South Ohio Avenue

Contact details are copied from each office’s official page and were checked against it on October 24, 2026.

Off-grid gear

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

These are affiliate links — we may earn a commission, at no cost to you. As an Amazon Associate, Bolthole Index earns from qualifying purchases.

Does Mercedes, Texas have zoning?

Yes. Mercedes adopted a zoning ordinance, and land inside city limits must conform to the regulations for its mapped district1. The city's zoning page says Mercedes currently has sixteen categories of zoning4, and the ordinance's own text lists them as part of the zoning map8.

Check the district before you buy, because the rules differ by district. In the Class A Single-Family Residence District, the ordinance requires a front yard at least 40 feet deep, unless an established building line sets the depth, and a rear setback of at least 10 feet for the main building6. Buildings in that district may not exceed 40 feet in height7. Servant's quarters on the same lot are allowed only as bona fide quarters that are not for rent9.

RV, tiny-home and manufactured-home rules inside the city are not confirmed. Ask the City of Mercedes before you plan to live in one3.

Do you need a building permit in Mercedes, and who issues it?

Inside Mercedes, building permits come from the City of Mercedes, not from Hidalgo County. The city code sets permit and inspection fees through a fee schedule, and starting work without a permit doubles the fee5. The city's website has a building permits page under Building and Renovating3.

Hidalgo County's development permit applies to unincorporated land and does not govern a lot inside Mercedes10. We could not confirm the city's step-by-step permit application, when inspections are required, or any owner-builder exception. Call City Hall at 956-565-3114 before you pour a foundation3.

Subdividing is regulated too: the city's subdivision ordinance requires plats to go to the city planning commission11.

How do septic permits work inside Mercedes?

They mostly do not, because Mercedes does not allow new septic systems. The city enforces Texas Health and Safety Code Chapter 366 and adopts the state's on-site sewage rules inside city limits, with a city code-enforcement officer as designated representative12. Its ordinance states: no new on-site sewage facilities will be allowed2. A new home inside the city therefore has to connect to city sewer, and we could not confirm the connection rules, so ask City Hall about water and sewer availability for a specific lot3.

Hidalgo County's septic program applies only outside incorporated municipalities13. If the land you are looking at is outside Mercedes city limits, see the Hidalgo County page.

Building a home in Mercedes: the steps, in order

  1. Confirm the lot is inside city limits and find its zoning district with the City of Mercedes4.
  2. Check district setbacks and height; for Class A single-family lots the front yard is at least 40 feet and height is capped at 40 feet67.
  3. Ask about sewer connection, since no new septic systems are allowed2.
  4. If the lot must be divided, take a plat to the city planning commission11.
  5. Get a building permit from the city and pay the scheduled fee; starting early doubles it5.
  6. Texas exempts owners from state electrician licensing on a dwelling they own and live in, but that is not an exemption from local permits or inspections14.

What stays with Hidalgo County, and what to check before you buy

Hidalgo County says it has no zoning authority under the Texas Local Government Code, so zoning inside Mercedes comes only from the city15. Floodplain rules, driveways onto state highways and groundwater wells can still involve other agencies. A driveway onto a state highway needs a TxDOT permit on Form 105816, and wells may need a groundwater conservation district permit where one exists17.

County figures that apply to Hidalgo County as a whole: the effective property tax rate is 1.8%18 and the median property tax bill is $2,187 a year19. For land outside city limits, use the Hidalgo County page, where different rules apply.

Watch-outs

  • Mercedes's code says no new on-site sewage facilities will be allowed, so a lot without city sewer access may not be buildable by septic2.
  • Starting construction without a city permit doubles the permit fee5.
  • We could not confirm the city's rules on RVs, tiny homes, manufactured homes, minimum house size or short-term rentals; ask City Hall at 956-565-31143.
  • Hidalgo County's rules for unincorporated land do not apply inside Mercedes, and the city's zoning does not apply outside city limits10.

Sources

  1. Exhibit 14A Zoning Ordinance, Article 2 General (Mercedes), quoted and re-checked
  2. Code of Ordinances, Article 13.05 On-Site Sewage Facilities (Mercedes), quoted and re-checked
  3. City of Mercedes (City Hall) (cityofmercedes.com)
  4. City of Mercedes Planning and Development (zoning and rezoning) (cityofmercedes.com)
  5. Code of Ordinances, Article 3.02 Construction Codes and Standards (Mercedes), quoted and re-checked
  6. Exhibit 14A Zoning Ordinance, Article 4 Class A Single-Family Residence District (Mercedes), quoted and re-checked
  7. Exhibit 14A Zoning Ordinance, Article 4 Class A Single-Family Residence District (Mercedes), quoted and re-checked
  8. Exhibit 14A Zoning Ordinance, Article 2 General (Mercedes), quoted and re-checked
  9. Exhibit 14A Zoning Ordinance, Article 4 Class A Single-Family Residence District (Mercedes), quoted and re-checked
  10. Construction Permit, quoted and re-checked
  11. Exhibit 10A Subdivision Ordinance (Mercedes), quoted and re-checked
  12. Code of Ordinances, Article 13.05 On-Site Sewage Facilities (Mercedes), quoted and re-checked
  13. Hidalgo County Permitting Procedures, quoted and re-checked
  14. Exemptions to Electrician Licensing (Texas statewide rule), quoted and re-checked
  15. Fair Housing Activity Statement – Texas, quoted and re-checked
  16. Section 4: Driveway Permits, Design, and Materials (Texas statewide rule), quoted and re-checked
  17. Water Code Chapter 36 — Groundwater Conservation Districts (Texas statewide rule), quoted and re-checked
  18. Effective property tax rate: Bolthole Index county data
  19. Median property tax bill: Bolthole Index county data

Written October 24, 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 Mercedes

Mercedes’s own rules

  • Local zoningPresent (with conditions)

    Land inside Mercedes city limits, subject to the zoning-map district in which the land is located.

    • Uses, erection, alteration, and enlargement must conform to the regulations for the mapped district.
    “The zoning regulations and districts as set forth in this ordinance are hereby approved and established”
  • Zoning districtsPublished (with conditions)

    Zoning districts and zoning map inside Mercedes city limits.

    • The ordinance states that the listed districts and map notations, references, legends, and information are part of the ordinance.

    listed districts: 16 districts (The text says fourteen (14) [sixteen (16)])

    “The City of Mercedes is hereby divided into fourteen (14) [sixteen (16)] districts”
  • Who permits septicLocal (with conditions)

    On-site sewage facilities in incorporated Mercedes.

    • The city enforces Texas Health and Safety Code Chapter 366 and adopts TCEQ on-site sewage rules, with a city code-enforcement officer as designated representative.
    “The rules adopted by this article shall apply to all the incorporated area of the city.”
  • Septic permitLimited

    New on-site sewage facilities in incorporated Mercedes.

    • Existing structures discharging to an on-site sewage facility must comply with the adopted rules; this claim concerns new facilities.
    “No new on-site sewage facilities will be allowed.”
  • Subdividing landRegulated (with conditions)

    Subdivision of land within Mercedes city corporate limits.

    • The ordinance also covers land within five miles of the city; this claim is limited to land within city limits. It requires and regulates preparation and presentation of plats to the city planning commission under stated procedures.
    “REGULATING THE SUBDIVISION OF LAND SITUATED WITHIN THE CORPORATE LIMITS OF THE CITY OF MERCEDES, TEXAS OR WITHIN 5 MILES THEREOF; ESTABLISHING SUBDIVISION DESIGN STANDARDS; PROVIDING IMPROVEMENTS TO BE MADE OR GUARANTEED TO BE MADE BY THE SUBDIVISION AND PRESCRIBING THE SPECIFICATIONS OF SUCH IMPROVEMENTS; REQUIRING AND REGULATING THE PREPARATION AND PRESENTATION OF PLATS TO THE CITY PLANNING COMMISSION AND SETTING FORTH THE PROCEDURES TO BE FOLLOWED BY THE CITY PLANNING COMMISSION IN APPLYING THESE RULES, REGULATIONS AND STANDARDS IN ORDER TO PROCURE THEIR APPROVAL;”
  • Permit feesPublished (with conditions)

    Building and construction permits inside Mercedes city limits.

    • The construction-code article directs that permit and inspection fees are in Appendix A; starting work without a permit doubles the appropriate fee.
    “Permit and inspection fees are as set forth in the fee schedule”
  • Permit processPartial

    Subdivision plat approval inside Mercedes city limits.

    • The located procedure concerns subdivision plats; a full building-permit application process was not located.
    “REQUIRING AND REGULATING THE PREPARATION AND PRESENTATION OF PLATS TO THE CITY PLANNING COMMISSION AND SETTING FORTH THE PROCEDURES TO BE FOLLOWED BY THE CITY PLANNING COMMISSION IN APPLYING THESE RULES, REGULATIONS AND STANDARDS IN ORDER TO PROCURE THEIR APPROVAL;”

Rules another office applies inside Mercedes

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

  • SetbacksSpecified

    Class A Single-Family Residence District inside Mercedes city limits.

    • A pre-established building line can establish the front-yard depth; double-frontage lots need front yards on both streets; corner-side-yard setbacks and recorded-plat setbacks may apply.

    front yard depth: >= 40 feet (Established building line may control) · primary rear setback: >= 10 feet · accessory-building rear setback: >= 4 feet (Or the easement boundary, whichever is greater)

    “There shall be a front yard having a minimum depth of forty (40) feet provided, that if a building line has been established by ordinance or by one (1) or more buildings in one block on the same side of the street, this line shall establish the minimum depth of the front yard.”
  • Building heightSpecified

    Class A Single-Family Residence District inside Mercedes city limits.

    maximum building height: <= 40 feet

    “No building shall exceed forty (40) feet in height.”
  • Accessory dwellingsLimited

    Class A Single-Family Residence District inside Mercedes city limits.

    • The quarters must be bona fide servant's quarters, cannot be rented, must be for servants employed on the premises, and must meet the stated front and street-line locations.

    front lot-line distance: >= 60 feet (Bona fide servant's quarters) · other street-line distance: >= 10 feet (Bona fide servant's quarters)

    “bona fide servant’s quarters, not for rent”

Still unanswered

We looked and could not find an official answer yet. Silence is not permission; ask Mercedes or Hidalgo County directly.

  • Owner-builder exemption — Owner-built residential work inside Mercedes city limits.
  • Inspections — Residential construction inside Mercedes city limits.
  • Certificate of occupancy — Residential occupancy inside Mercedes city limits.
  • Minimum dwelling size — Dwellings inside Mercedes city limits.
  • Lot coverage — Lots inside Mercedes city limits.
9 more unanswered
  • Living in an RV
  • Camping on your land
  • Tiny homes
  • Manufactured homes
  • Septic inspection
  • Mandatory utility hookup
  • Agricultural exemption
  • Driveway access
  • Short-term rentals

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 Mercedes publishes no rule on the point, not that none exists. Hidalgo County’s page lists the county offices to call.

← All of Hidalgo County: county rules, score and offices