Cities | Brownsville

Brownsville Multiplex Rules 2026: ADUs, Duplexes, R-3 Apartments and Small Lots

Brownsville zones the land inside its city limits, so the first question for any project is the lot's zoning district. The rules sit in the City's Unified Development Code (UDC), which covers zoning, subdivisions, signs, trees, flood damage prevention and stormwater. The City Commission changed the UDC on January 6, 2026, and again on June 16, 2026, when it rewrote the district tables, cut parking to one space per home and added rules for the 2025 state housing laws. This page gives the main numbers, with the section for each, and links to seven detailed pages.

Brownsville Guide Pages

Where the Current Code Is

The UDC is Subpart B of Brownsville's Code of Ordinances on municode, the online code library the City uses. The version there is Supplement 26, "Codified through Ordinance No. 2026-1797, enacted January 20, 2026." Section 1.3 says the UDC, adopted as Ordinance Number 2020-235.95, took effect on March 31, 2021. The City's own website answered every VanPlex request with an access error, so this guide reads the code from municode and from municode's ordinance bank, which holds the signed ordinances.

Supplement 26 does not yet show the UDC ordinances the City Commission passed on January 6, 2026 (Nos. 2025-235.119 to 2025-235.125, including flood and stormwater changes, a sign rule for rezonings, a zoning check before platting and a plat exemption for single-family lots) or on June 16, 2026 (Nos. 2026-235.127, 2026-235.128 and 2026-235.130). This guide uses those ordinances where they changed the text. Some of the January scans drop words, and on municode Sections 4.6.4 to 4.6.13, which cover fences, accessory buildings and development in the overlays, have headings and no text. Ask the Planning and Redevelopment Department for those sections.

State Law in Brownsville, in Brief

Brownsville had 186,738 people in the 2020 Census, and Cameron County had 421,017. So Brownsville passes the size test in the 2025 laws, by VanPlex count from 2020 Census figures, as the more Texas cities page also lists. The City answered each law in 2026:

• SB 15 became Section 4.2.11.A.5, the "Small Lot Residential Development Modification": on five acres or more in RE, R-1 or R-2 with no recorded plat, lots of 3,000 square feet and 75 feet deep, 30 feet wide where parking comes from an alley, a shared driveway or a slip street, with density "Not applicable."
• SB 840 is named in Ordinance No. 2026-235.127. Corridor Commercial and Regional Center already allowed multifamily by right at 45 feet, and the ordinance added a rule that the City Engineer will not ask for a traffic study when an existing nonresidential building converts to homes. Light Industrial still allows warehouses and no homes.
• HB 24 became the protest rules in Section 4.2.2.F and G, and notice signs of at least 24 by 48 inches.

The state protest rule is Local Government Code 211.0061, in force since September 1, 2025. It keeps two protests. Under 211.0061(b)(1), owners of "at least 20 percent of the area of the lots or land covered by the proposed change" can still force a vote of "three-fourths of all members of the governing body," for any change. Under 211.0061(b)(3), for a change that "has the effect of allowing more residential development" and adds no commercial or industrial use beyond a limited first floor, a protest by owners of the adjoining land within 200 feet needs "at least 60 percent" of that land, and the change then needs "a majority of all members of the governing body." The City's June 2026 text prints this rule with lettering errors, covered under the disagreements below; the statute controls.

How a Lot Reaches Two, Three or More Homes

Source: Brownsville UDC on municode, Supplement 26 (Section 4.4.3 and Section 4.4.4), with the district tables, parking and definitions from Ordinance No. 2026-235.127, June 16, 2026.

Zoning Districts

Table 4.1-1 sets five residential districts (AG, RE, R-1, R-2 and R-3), four nonresidential districts (CC, RC, LI and HI) and six traditional neighborhood and downtown districts (TN, TN-MU, TN-C, DE, DG and DC), with a Historic Overlay, an Airport Overlay, Planned Development Districts and, since June 2025, a Medical Overlay District. A rezoning goes to a Planning and Zoning Commission hearing and a City Commission vote, with mailed notice to owners within 200 feet and a sign on the property, and a residential application of up to 1 acre costs $500. Between March and September 2026 the City rezoned six sets of R-1 land to R-2 for duplexes. The zoning districts page has the use chart and the protest rules.

Accessory Dwelling Units and Duplexes

Section 4.4.4 allows "No more than one (1) Accessory Dwelling Unit for the purpose of a living quarters" on a lot. It may be up to 50 percent of the main house's living space, keeps the main house setbacks, "may be rented or occupied by a guest," may have its own meter, and needs one parking space. A duplex is "A single principal building located on a single lot that contains exactly two dwelling units," allowed by right in R-2, R-3, TN, TN-MU, TN-C and DE. The ADUs and duplexes page covers both, including a numbering error in the use chart.

Townhomes and Apartments

A townhouse row joins two to six units, each on its own platted lot, 30 feet wide and 50 feet deep at most. R-3 allows buildings of any number of homes on lots at least 100 feet wide, up to 45 feet tall, and a building of more than three homes needs Site Plan approval. The districts around downtown add cottage rows, cottage courts and small apartment buildings on 100-foot lots. On commercial land, CC and RC allow apartments by right at 45 feet and one space per home. The townhomes and multifamily page has the details and the SB 840 comparison.

Lots, Yards, Height and Parking

Minimum lots run from 40,000 square feet in AG and 20,000 in RE to 5,000 in R-1 and 2,000 in R-2 and R-3. Since June 16, 2026 the R-1, R-2 and R-3 front setback is 10 feet, a front garage sits 25 feet back, houses may be 35 feet and 3 stories (45 feet in R-3), and buildings may cover 70 percent of a lot in RE to R-3. A story now counts as 10 feet, and where feet and stories conflict "the greater of the two shall prevail." Every home type needs one parking space per home, half that in the TN districts and none downtown. The lot size page and the parking, setbacks and height page have the numbers.

Flood, Drainage and Windstorm

Section 5.5 adopts the Cameron County flood study and maps dated February 16, 2018. A new home in a special flood hazard area puts its lowest floor 2 feet above the base flood elevation, and a home outside it sits 2 feet above the highest adjacent grade. The January 2026 amendments require fill in a flood zone to be offset at a 1:1 ratio and detention for sites over half an acre. Cameron County is a first tier coastal county, and a Texas Windstorm Insurance Association policy needs a Texas Department of Insurance certificate of compliance. The flood, drainage and windstorm page has the details.

What the Numbers Show

Brownsville had 192,957 people on July 1, 2025, by the Census Bureau's Vintage 2025 estimate, up from 186,738 in the 2020 Census. The Census Bureau's 2025 Building Permits Survey file shows Brownsville reported all 12 months, with these counts:

Source: Census Bureau Building Permits Survey, South Region places, 2025 annual. Brownsville's Texas row (place code 10768) shows 12 months reported, so the estimate and reported columns are the same.

The Census counts a building by the number of homes it holds, so a fourplex is one building of three to four units. The file gives counts only. It shows no two-unit buildings permitted in Brownsville in 2025; the duplex rezonings listed on the zoning page came in 2026.

Plats, Permits and Fees

City staff decide preliminary, final, minor and amending plats, and the decision-maker acts within 30 calendar days after an application passes the completeness check; the state rule in Local Government Code 212.009 counts its 30 days from filing. Since January 6, 2026, a plat is accepted only if the use planned for the new lots is allowed by its zoning, and a lot that held a single-family home can sometimes skip platting to rebuild. The FY 2027 Master Fee Schedule lists a minor residential subdivision of up to 1 acre at $350. New homes on two net acres or more pay a park fee of $500 per home, and a new home pays a roadway capital recovery fee of $1,000 at building permit under Chapter 9, unless exempt, rising 5 percent a year for four years. The plats, permits and fees page has the full lists.

Where the City's Documents Disagree

VanPlex found these while reading the UDC and the 2026 ordinances:

• The protest text adopted June 16, 2026 drops the 20 percent protest by adjoining owners for changes outside the residential case, gives the three-fourths vote to the 60 percent protest, refers to an item "F.2.c" that does not exist, and cites "211.061(c)" for 211.0061(c).
• Section 4.2.2.H requires three-fourths after a Planning and Zoning Commission denial, while HB 24 repealed Section 211.006(f) of the Local Government Code.
• The small lot rule allows 30-foot lots only with alley or shared access and keeps a 25-foot front garage setback, while SB 15 bars lots wider than 30 feet and front setbacks above 15 feet on small lots.
• CC and RC limit homes near residential districts to 25 percent of the neighboring density, while SB 840 sets a floor of 36 homes per acre; LI allows warehouses and no homes.
• The use chart says townhouses may share one lot and duplexes may sit on two; the June 2026 definitions put each townhouse on its own lot and a duplex on one lot.
• The ADU row in the use chart points to standard 24 (and RE to standard 4), while the ADU rules are item 25.
• The June 2026 tables print no homes-per-acre limit, while building types and the CC and RC transition rule still refer to density.
• Plats subject to the Model Subdivision Rules carry a note of one single family detached dwelling per lot, beside zoning that allows duplexes and ADUs.
• The fee schedule lists a commercial park fee of $2,000 per acre, where UDC Section 5.2.3.G sets $6,000.

Where a City text conflicts with state law, the statute controls. Section 1.7.2 says that where City rules conflict with one another "the more restrictive provision governs unless otherwise expressly stated." For a definition or a fee, ask the Planning and Redevelopment Department in writing which text it applies to your lot.

Where to Go Next

Related on VanPlex: the insurance and flood page, financing 2 to 4 units and the Texas multiplex guide overview.

Frequently Asked Questions

Official sources (checked October 2026)