San Antonio, TX Building Setbacks & Zoning: Setback Rules (2026)

Every zoning district in San Antonio carries its own setback minimums, spelled out district-by-district in Table 310-1 of UDC Sec. 35-310, the Lot and Building Dimensions Table. For the large-lot single-family districts, RE and R-20 require a 10-foot front setback, 5-foot side setback and a 30-foot rear setback. The smaller single-family districts R-6, R-5 and R-4 keep the same 10-foot front and 5-foot side minimums but the rear setback falls to 20 feet, and in the compact R-3, R-2 and R-1 districts the rear setback shrinks further to 10 feet, 5 feet and 5 feet respectively.

Multi-family districts such as RM-6 use a 10-foot front, 5-foot side and 20-foot rear setback, while commercial districts like C-1 and C-2 carry different front, side and rear figures entirely. Sec. 35-310(a) makes the table binding: no building permit may be issued unless the proposed development conforms to these design regulations, so the setback lines are not aspirational, they gate permit issuance. Sec. 35-516 layers on supplemental rules the table itself does not spell out: an existing residence with a 3-foot or more side yard can keep that line on an addition, but never below 3 feet; up to 15 feet of an abutting alley or utility easement can count toward the required rear or side yard; and reversed corner lots must match the front setback of the lot behind them.

Swimming pools are barred entirely from any front setback and must sit at least 5 feet off side and rear lines if excavated more than 3 feet deep. Garages need 20 feet of clearance from the sidewalk or property line for driveway-accessed entries. Where a subdivision plat imposes tighter setbacks than the UDC through private covenants, the city will not enforce those private lines, only the Table 310-1 minimums.