Arlington | Lot Size and Small Lots
Arlington Lot Size and Small Lots: District Minimums, Replats and SB 15
In Arlington, each zoning district sets a smallest lot, a narrowest width and a shallowest depth. A new lot must meet them, and a split of an existing lot must also match the block around it. Since September 1, 2025 the Unified Development Code (UDC) also has separate small-lot rules for large unplatted tracts, written to follow the state law SB 15. This page gives the numbers and says where the City's small-lot table and the state law do not match. The Arlington overview gives the short version.
Arlington lots in six facts
- The smallest lot for a detached house is 5,000 square feet and 50 feet wide, in RS-5 and RM-12; RE needs one acre and 100 feet of width. Source: Arlington UDC, Sections 2.2.2 to 2.2.7
- A replatted lot must match the width, depth and area of the lots that set the pattern on the same block. Source: Arlington UDC, Sec. 10.4.17.F
- A recorded single-family lot smaller than its district minimum can still get a house if it is at least 50 feet wide and 5,000 square feet, or within 10 percent of the minimum. Source: Arlington UDC, Sec. 11.3.2
- Section 5.5.6 allows small lots of 3,000 square feet, 30 feet wide and 75 feet deep, on unplatted single-family tracts of 5 acres or more. Source: Arlington UDC, Sec. 5.5.6, Table 5.5-7
- Small-lot tracts within 3,000 feet of an airport are excluded, the same distance that SB 15 sets in Local Government Code 211.052. Source: Arlington UDC, Sec. 3.2.1.A.3
- Arlington requires 35 percent of a small-lot site as common open space; Local Government Code 211.055 bars requiring more than 30 percent open space on a small lot. Source: Arlington UDC, Sec. 5.5.6.C.3
Lot Sizes by District
Each residential district page in Section 2.2 has a box headed "C. Lot Dimensions." The table below copies those boxes. Gross living area is the smallest floor area a home may have, and lot coverage is the share of the lot that buildings may cover. Under Section 4.1.4, coverage counts "primary and accessory buildings," and for single-family homes it does not count paving, pools, decks or uncovered patios.
| District and home type | Lot area, min. | Lot width, min. | Lot depth, min. | Gross living area, min. | Lot coverage, max. |
|---|---|---|---|---|---|
| RE | 1 acre | 100 ft | 150 ft | 2,500 sq ft | 50% |
| RS-20 | 20,000 sq ft | 100 ft | 150 ft | 2,200 sq ft | 50% |
| RS-15 | 15,000 sq ft | 80 ft | 100 ft | 2,000 sq ft | 50% |
| RS-7.2 | 7,200 sq ft | 60 ft | 100 ft | 1,500 sq ft | 50% |
| RS-5 | 5,000 sq ft | 50 ft | 100 ft | 1,500 sq ft | 60% |
| RM-12, house | 5,000 sq ft | 50 ft | 100 ft | 1,500 sq ft | 60% |
| RM-12, duplex | 6,000 sq ft | 60 ft | 100 ft | 800 sq ft | 60% |
| RM-12, townhouse | 2,900 sq ft | 20 ft | 100 ft | 800 sq ft | 75% |
| RMF-22, duplex | 6,000 sq ft | 60 ft | 100 ft | Not listed | 80% |
| RMF-22, townhouse | 2,900 sq ft | 20 ft | 100 ft | Not listed | 90% |
| RMF-22, apartments | 15,000 sq ft | 60 ft | 100 ft | Not listed | 90% |
| VG, house | 7,200 sq ft | N/A | N/A | Not listed | 40% |
Source: Arlington UDC, Sections 2.2.2 to 2.2.9, PDF amended by Ordinance No. 25-059. RMF-22 lists no gross living area ("2. Reserved"); VG lists no width or depth.
Three rules change the numbers in the table. Under Section 4.1.3.B, in RE, RS-20, RS-15, RS-7.2 and RS-5 "the Zoning Administrator may reduce the minimum gross living area to 1,000 square feet where a smaller unit size is consistent with existing development in surrounding neighborhoods." The RS-15 page allows one side setback of 5 feet if the other side is 15 feet. And Section 4.1.2 says lot area means "the total gross lot area," and that existing platted lots "shall not be made nonconforming by the acquisition of public right-of-way."
Corner Lots and Lots on Busy Streets
Section 4.1.5 adds width in three cases for one- and two-family homes:
- Corner lot on an arterial. A corner lot with "a side lot line abutting an arterial street" must "provide an additional 20 feet in lot width."
- Other corner lots. "All other corner lots for residential use shall provide an additional ten feet of lot width over the minimum standards."
- Direct access to a major collector. Lots for one- or two-family homes "that have direct access on to a major collector shall have a minimum lot width of 120 feet."
An arterial is a large through street on the City's Thoroughfare Development Plan, and a collector is the next size down. In RS-5, where the base width is 50 feet, a corner lot needs 60 feet, or 70 feet beside an arterial, by VanPlex arithmetic. The 120-foot rule matters for any plan to put homes with their own driveways on a collector street.
When You Need a Plat
A plat is the recorded map that creates legal lots. Section 6.1.4 says "every owner of any tract of land who divides the tract into two or more parts shall cause a plat to be made." This covers a division "regardless of whether it is made by using a metes and bounds description in a deed of conveyance or in a contract for a deed." A metes and bounds description is a written boundary made of distances and directions, which some owners use to sell part of a lot without a new map. In Arlington that still needs a plat.
The plat must be approved and recorded before construction. The Zoning Administrator "shall not issue permits for any construction activity or allow any public improvements for a development until a plat is approved and filed of record," except for land covered by Section 6.1.3 or "a plot or tract conveyed prior to May 29, 1952, and remaining in the same configuration." Section 6.1.3 itself exempts a division "into parts greater than five acres where each part has access and no public improvement is being dedicated." A conveyance plat, which only records lot lines for a sale, gives no right to build: "No building permit shall be issued nor public utility service provided for land that has only received approval as a conveyance plat."
Section 6.3.1 adds four lot rules. Every building must be on a lot. Every lot must "front on a public or private street or private access easement." "Platted or replatted lots must comply with the minimum lot size regulations of the zoning district." And "newly platted or replatted lot lines shall conform to existing zoning district boundaries," so one lot cannot straddle two districts. The plats, permits and fees page covers the plat types, deadlines and fees.
Splitting an Existing Lot: the Block Pattern Rule
Splitting a platted lot means a replat, a new plat that replaces part of a recorded one. Section 10.4.17.F holds a replat to the final plat criteria and adds one more: "lots must conform in width, depth, and area to the predominant pattern established by the existing lots located on the same block, having due regard to the character of the area." The Planning and Zoning Commission decides replats.
This rule reaches further than the district minimum. A 14,000 square foot lot in RS-5 is large enough for two 7,000 square foot lots under the district minimum, but if the other lots on the block are all 14,000 square feet, two half-size lots would not match the block's pattern. The code gives "predominant pattern" no number, so the commission decides each case. Ask the planning staff how they have applied it on your block before you buy a lot to split.
State law adds notice for some replats. If the area was limited in the past five years to "not more than two residential units per lot" by zoning or by deed restrictions, Local Government Code 212.015 applies. Arlington Section 10.4.17.J then requires written notice to "each lot owner of record within 200 feet of the lots replatted not later than the 15th day after the date the replat is approved." Every replat must also carry the line "This plat does not alter or remove existing deed restrictions or covenants, if any, on this property." Section 1.7.3 says the code does not "modify or repeal any private covenant or deed restriction," and that the City is not obligated to enforce them, so private restrictions still bind the new lots.
Building on an Older Small Lot
Many Arlington lots were platted before the 2014 code. Section 11.3.2 says that if a lot of record "created by a subdivision plat has less width or area than the minimum requirements," that shortfall does not stop "a detached single-family dwelling or an accessory structure" if "the lot is at least 50 feet in width and 5,000 square feet in area" or its width and area "do not vary more than 10 percent from the minimum requirements." In RS-7.2, for example, a platted lot of 6,500 square feet and 54 feet wide stays within 10 percent of 7,200 and 60, by VanPlex arithmetic.
Section 11.3.3 adds a limit. "If two or more adjacent and vacant nonconforming lots are in single ownership," they "shall be considered in combination" and need "a combination or replatting of all necessary lots" before a building. An owner of two narrow vacant lots side by side may have to build on them as one.
SB 15 Small Lots: Who Qualifies
SB 15 added Local Government Code 211.051 to 211.058 on September 1, 2025. It applies in a city of more than 150,000 people in a county of more than 300,000. Arlington had 394,266 people in the 2020 Census and Tarrant County had 2,110,640, so Arlington is covered by VanPlex count. The law covers only a tract that "will be platted and located in an area zoned for single-family homes," "is five acres or more," and "has no recorded plat," and it excludes land within "3,000 feet of an airport or military base."
Arlington's version is Section 5.5.6, added by Ordinance No. 25-059. Section 3.2.1.A.3 copies the state test: "an unplatted tract of land of 5 acres or more located in an area zoned for single-family residential," with "no recorded plat," and "not located within 3,000 feet of an airport." Land near Arlington Municipal Airport is therefore out. The section's purpose is "residential lots as small as 3,000 square feet." A small-lot project needs a single-family small-lot development plan under Section 10.4.5D, decided by the Zoning Administrator, and the code requires no public notice for it (Section 10.3.6.H).
Section 5.5.6 serves developers of raw land. A recorded 7,200 square foot lot inside an existing subdivision already has a plat, so its owner would split it through the ordinary replat rules above.
Arlington's Small-Lot Table Against the State Limits
Table 5.5-7 sets the small-lot dimensions. The state law sets limits on what a city may require for a "small lot," which it defines as "a residential lot that is 4,000 square feet or less." The table puts the two side by side.
| Rule | Arlington, Sec. 5.5.6 | State limit, SB 15 |
|---|---|---|
| Lot area, house | 3,000 sq ft | May not require more than 3,000 sq ft (211.054) |
| Lot width, house | 30 ft | May not require wider than 30 ft (211.054) |
| Lot depth | 75 ft | May not require deeper than 75 ft (211.054) |
| Front setback | 15 ft | No more than 15 ft (211.055) |
| Rear setback | 10 ft | No more than 10 ft (211.055) |
| Interior side setback | 50 ft, as printed in Table 5.5-7 | No more than 5 ft (211.055) |
| Height | 3 stories (10 ft floor to ceiling) | May not require fewer than 3 full stories of up to 10 ft (211.055) |
| Parking, lot of 3,000 to 4,000 sq ft | 1 space per unit | No more than 1 space per unit, and no covered parking (211.055) |
| Open space | 35% of gross site as common open space | No more than 30% open space or permeable surface (211.055) |
Source: Arlington UDC, Section 5.5.6 and Table 5.5-7; Local Government Code 211.054 and 211.055, read from the Texas Legislative Council file server.
Seven of the nine rows match. Two conflict. Table 5.5-7 prints the interior side setback as 50 feet and the street side setback on "All roadways" as 50 feet, on a lot that may be 30 feet wide; Section 211.055 bars a setback "greater than" "five feet from the side of the property" on a small lot. And Section 5.5.6 requires developments "to preserve 35 percent of the site's gross area for common open space," while the statute bars requiring "more than 30 percent open space or permeable surface." Section 5.5.6 says its own standards "shall control" over other UDC sections, but a city "may not adopt or enforce" a rule the statute bars, and Section 211.058 lets an affected owner sue. Ask the Zoning Administrator in writing how the City applies both rows before you lay out lots.
Other parts of Section 5.5.6 shape a small-lot subdivision. Blocks may be no longer than 300 feet, with a mid-block open space at least 30 feet wide. "Vehicular access is required to be from the rear of the lots via alleys/private access easements," garages may be "only alley-loaded," and each home needs "a minimum of 60 square feet front porch." Projects with "more than 40 single-family lots" must "provide an amenity center and a pool," owned by a homeowners association. Duplexes are allowed "on minimum 5,000 square feet and 50-foot lot width" but may not exceed 30 percent of the housing types or of a block face.
Smaller Lots in Exchange for Trees
Arlington ties lot size to trees. Section 5.2.3 requires residential developments of one acre or more to preserve 35 percent of the protected tree inches on a site. If the preservation plan exceeds 35 percent, "the applicant may reduce the lot area, lot dimensional requirements, and/or dwelling unit size," by "one percent for each one percent increment" above 35, and the reductions "shall not exceed 15 percent." The incentive "shall not be applicable to small-lot single-family development." The trees, airport and historic page explains how the tree points are counted.
Best For
- ✓ An unplatted single-family tract of 5 acres or more, more than 3,000 feet from any airport, planned for 3,000 sq ft lots.
- ✓ A platted lot of record at least 50 feet wide and 5,000 sq ft that falls short of its district minimum.
- ✓ A replat on a block where the existing lots are already the size you plan.
Usually Fails When
- ✕ The plan splits a lot on a block of larger lots, against the block pattern rule.
- ✕ Two adjacent vacant small lots are owned together and the plan treats them as two building sites.
- ✕ A small-lot layout relies on 5-foot side setbacks without written City confirmation of Table 5.5-7.
What To Verify Before Spending Money
- → The district, any PD ordinance, and the recorded plat for the lot.
- → The distance from the tract to Arlington Municipal Airport and any other airport.
- → Deed restrictions recorded for the subdivision before a replat.
Where to Go Next
Related on VanPlex: the Arlington overview, the SB 15 small lots page, and how Texas zoning works.
Frequently Asked Questions
What is the smallest lot I can build a house on in Arlington?
Can I split my Arlington lot into two lots?
Can I build on an old Arlington lot that is smaller than the district minimum?
Does the SB 15 small lot law apply in Arlington?
Which land qualifies for Arlington small-lot development?
How much open space does an Arlington small-lot subdivision need?
How wide must a corner lot be in Arlington?
Does a platted building line still control setbacks in Arlington?
Can Arlington reduce my lot size for saving trees?
Who approves an Arlington small-lot development plan?
Official sources (checked October 2026)
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