San Antonio data center filings, Q3 2026: one new building registered near Castroville, and Texas halts state environmental permits for data centers.

The small hollow grey dots are data centers operating today, from the public PeeringDB facility list, each linked to its PeeringDB record. An operating building is context for the filings and is in no count on this page.

A registration's estimated cost is the registrant's and is not shown as a city value, so a project with no city permit says so. Values are never added together. A building's site, foundation and temporary power permits are listed with it and do not set its dates.

Texas Commission on Environmental Quality air authorizations in the eight counties since January 2025, limited to those whose facility or operator name identifies a data center. One falls in Q3 2026. Emergency generators are backup plant, listed here and never counted. Misae's permit is for on-site power and is counted in Q4 2025. Each link opens the agency's own document.

1. 22 Sep 2025Medina County: reinvestment zone on US 90 west of Castroville for a CyrusOne data center, 4-0 (minutes).
2. 3 Nov 2025Medina County: CyrusOne tax abatement agreement, 4-0 (minutes, agreement).
3. 14 Apr 2026Kendall County: Resolution R-20260414-5 on responsible data center development, 5-0 (minutes).
4. 21 Apr 2026Guadalupe County: development and tax abatement agreements with CloudBurst, each 3-2 (minutes).
5. 15 Jun 2026Atascosa County: no direct talks with a reported developer (release).
6. 7 Aug 2026San Antonio City Council: three members request a temporary moratorium (release).
7. 12 Aug 2026Medina County: Microsoft's 2021 Chapter 381 agreement terminated, effective this date (agreement).
8. 24 Aug 2026New Braunfels City Council: mayor's direction narrowed from a moratorium to rules reclassifying data centers, no action (minutes).
9. 25 Aug 2026San Antonio City Council: moratorium and code changes discussed, no vote (release).
10. 17 Sep 2026Fair Oaks Ranch City Council: data centers allowed by special use permit in the Logistics Zone only, adopted 7-0 (minutes, amendments).
11. 18 Sep 2026Public Utility Commission: large-load interconnection rule filed with the Texas Register, effective 8 October (record).
12. 21 Sep 2026Governor of Texas: environmental agency directed to halt permits sought by data centers until ERCOT completes its audit, update due 19 October (directive).

Projects reported in the press or in a record that does not say what it builds. None of these is in the counts above.

• CloudHQ SAT campus, western Bexar County. On CloudHQ's campus page. A 2022 city tree permit for underbrush clearing names CloudHQ at 15355 Lambda Drive (city record), and no building filing was found.
• Rowan's Cinco campus, Medina County. A replat of a lot in the Rowan Cinco subdivision on County Road 683, approved in February 2026 (minutes), and a project page, with no building registration.
• Rowan's Project Pirate, Medina County. About 340 acres on Rowan's project page, with no filing.
• Microsoft SAT82, Medina County. Registered in July 2024 (registration) and in December 2025 at another address (registration). The records do not show whether the second replaces the first.
• Stream Data Centers, 11203 W Military Drive. Registered in 2023 as 40 MW (registration), with 175 emergency generators registered with the state in January 2025 (acknowledgement, application). No later building phase is on record.
• Black Mountain Power, southern Bexar County. A 432-acre purchase reported by DCD, with no filing.
• Vantage Rogers Road stationary power. Six generator and electrical house permits issued to VoltaGrid in May 2026 (city record), with no rating, and permanence not shown.
• Fit-outs with no power figure. Vantage TX21 on Rogers Road, 2025 (city record, registration), and the COPT building for Amazon at Potranco, 2026 (registration). Both are inside buildings already on record.
• QTS San Antonio III, western Bexar County. Only the 2021 SAT2-DC1 registration, and no later phase found.
• AWS LBB120 Horizon Junction, Medina County near Lytle. No filing, county record or Amazon statement.
• Microsoft SAT91, Medina County. No registration or county record under that name.
• CloudBurst, Guadalupe and Comal counties. Guadalupe County agreements of April 2026 (minutes). Near New Braunfels the state acknowledged a CloudBurst engine registration in October 2025 (air record), and a separate air application describes gas engines for on-site data center power (summary) with no rating. The record does not show whether the two counties' sites are one campus, and there is no building filing.
• Data center on FM 1101, New Braunfels. A pre-development meeting request, DVS26-669, filed 24 June 2026 (city records, search DVS26-669). The developer is not named.
• Registered before 2025, status not in the records. CyrusOne SAT 8 and 9 on Omicron Drive (registration), Microsoft SAT16 and SAT17 on Westover Link (first, second), Microsoft SAT81 in Medina County (registration) and an American Tower data center on New Highway 90 West (registration).
• AI data center near Comfort, Kendall County. A March 2025 discussion in a regional summary (packet), with developer and site unconfirmed.
• Unnamed developer, Atascosa County. The county could not confirm a reported proposal (release).

Boundary. The San Antonio-New Braunfels metropolitan area as defined in OMB Bulletin 23-01: Bexar, Comal, Guadalupe, Medina, Atascosa, Wilson, Kendall and Bandera counties. Hays and Travis belong to the Austin metro (our Austin coverage). CloudBurst's San Marcos campus straddles Guadalupe and Hays, so only its records inside the eight counties are listed.

Records read. State construction registrations in all eight counties, by project name and by data center owner. City of San Antonio permit applications for 2026 and permits issued since January 2025, through 30 September, which are partial because a 2025 application not yet issued is not published and a record naming no data center, operator or campus is missed. New Braunfels and Converse permit records for all seven quarters, which show no data center building filing. The state's air authorizations whose facility or operator name identifies a data center. Commissioners court agendas and minutes in all eight counties, Guadalupe and Atascosa in part, and council records in San Antonio, New Braunfels and Fair Oaks Ranch. Other cities' permits are not in the record, and Guadalupe's and Kendall's county permit portals require an account.

What is counted. Filings that add data center buildings or capacity: new buildings and the jobs filed for them, and, inside a data center already on record, work whose filing states added power with a figure, such as Vantage's 32 MW and 96 MW fit-outs. A power plant counts when its permit states its rating and that it serves a data center, as Misae's does. Emergency generators, fit-outs with no power figure, replacements, repairs, renovations, offices, fire and life-safety work, temporary power and renewals do not.

Counting. A site is one address or one campus, counted once in a quarter in which it files, however many filings it makes, so Vantage's Omicron Drive buildings are one campus and its Rogers Road buildings another. A project is dated by its own first filing, state or city, and its site, foundation and temporary power permits belong to it. Megawatts are quoted as the record states them and never summed.

Kinds of filing. A state construction registration is an accessibility filing, not a permit to build, and its dates and costs are the registrant's estimates. A state air permit governs emissions, not construction. A city permit is the city's approval to build.