The site
The site from above
Power
Power and the grid
The plan on record is a grid connection. A building on the campus is in service.
We checked utility filings, regulator dockets and air-permit records for this campus.
Permits
Permits checklist
3 granted · 4 checked, nothing on file
Approvals a campus like this normally needs (including an air permit for backup generators), and what we found.
- ✓Site plan GrantedCity of El Mirage · March 16, 2021: Site plan approved by City of El Mirage. Local government · March 2021
- ✓Air permit GrantedMaricopa County Air Quality Department · March 16, 2021: Air permit approved by Maricopa County Air Quality Department. Local government · March 2021
- ✓FAA airspace clearance Grantedthe FAA: FAA airspace clearance granted by the FAA. FAA · Oct. 2026
- –Checked, nothing on file: Zoning approval, Building permit, Water and wetlands permits, Utility and grid approval
Money
Money on record
$258M Land purchase (Land acquisition). News report · May 2024
Timeline
What happened, and what is due
SitePaper trailConstructionPowerPermitsMoneyLegalUpcoming
- March 16, 2021Permits Site plan approved by City of El Mirage. Local government · March 2021
- March 16, 2021Permits Air permit approved by Maricopa County Air Quality Department. Local government · March 2021
- June 2021Site Microsoft launched the West US 3 Azure region in June 2021. News report · Dec. 2024
Construction activity
Satellite captures by quarter
Since Sept. 2025: 2 satellite captures.
Satellite
’26
Dot size: records in the quarter, largest = 1. Two-digit years mark each first quarter.
Who is involved
Owners, partners and builders
Owners and developers
- Microsoft, operator
- Dermody Properties, landowner
Builders and advisers
- Stantec, design team
Still unknown
Open questions
- IT capacity actually running today.
- Remaining build-out and its timing.
Where this comes from
39 records from 11 documents
Drawn from news reports, local government records, public and commercial datasets, state agency records, satellite captures and company statements, each kept with its date and source. The bar shows documents by type.
News report 4Local government 2Dataset 2State agency 1Satellite 1Company 1
Evidence
Every quote behind this page
Grade key: A = the primary record itself (permit, filing, exhibit) · B = a dated official statement · C = news reporting. Map distances are our own measurements on OpenStreetMap and carry no grade. Allegations in lawsuits are marked as such in the quotes.
Power (8)
- Stage: IN SERVICE - PHX-80 completed and operational; the campus has served IT capacity since 2021 as part of Azure West US 3 (region launched June 2021); PHX-81/PHX-82 permitted and under construction; PHX-83 filed Dec 2024“connected to the existing onsite substation operated by Arizona Public Service (APS)”Local government · April 2024 · grade B
- Power step: energized“connected to the existing onsite substation operated by Arizona Public Service (APS)”Local government · April 2024 · grade B
- Utility: Arizona Public Service (APS)“Water: City of El Mirage Sewer: EPCOR (Private Company) Electric: APS”Local government · March 2021 · grade B
- Role of the on-site plant: backup“The generators are for emergency backup power only”Local government · March 2021 · grade B
- On-site power technology: diesel generators (standby backup)“Twenty-one, diesel-fueled emergency generators will be installed for the proposed project. The proposed generators will be permitted with the Maricopa County Air Quality Department (MCAQD)”Local government · March 2021 · grade B
- Size status: not stated in any primary record - no mw it / mw utility figure exists for this campus in Microsoft, City of El Mirage or APS records found through Oct 20, 2026“Power will be provided by the existing Arizona Public Service on-site substation”News report · Oct. 2026 · grade C
- Size status: not stated in any primary record - no mw it, mw utility or contract-demand figure, and no ADEQ/Maricopa County generator-nameplate ceiling, exists for PHX-80 in Microsoft, City of El Mirage, APS/ACC or Maric“Power will be provided by the existing Arizona Public Service on-site substation”News report · Oct. 2026 · grade C
- a Maricopa County air-permit generator-inventory search angle returned nothing indexable; DCD (Dec 2024) confirms PHX-80 completed and operational (PHX-83 is the fifth building) with no MW stated.“Power will be provided by the existing Arizona Public Service on-site substation”News report · Dec. 2024 · grade C
Money and contracts (5)
- Project status: OPERATING (IN SERVICE) AND EXPANDING: PHX-80 is completed and operational (first building launched 2021, Azure West US 3 region launched June 2021); PHX-81 and PHX-82 are permitted and under construction;“Under the original authorized site plan, PHX-80 is completed and operational, while PHX-81 and PHX-82 are permitted and under construction”News report · Dec. 2024 · grade C
- Three further data-center buildings (750,000 sq ft) are planned on the 283-acre expansion parcel under the May 2024 development agreement, reportedly zoned for a further three buildings beyond PHX-83.“The PHX-83 extension is set to be on the original 150 acres; the additional acreage acquired this year is reportedly zoned for a further three buildings”News report · Dec. 2024 · grade C
- Expansion land acreage: 283 acres“Microsoft paid $258 million in all cash on May 31 for approximately 283 acres in El Mirage along Northern Parkway and Dysart Road”News report · May 2024 · grade C
- land purchase: land acquisition 258081239 USD“The $258,081,239 sale price equates to $912,657.33 per acre”News report · May 2024 · grade C
- development agreement: development agreement“In May, Dermody received city approvals from El Mirage for a development agreement for three data center buildings totaling 750,000 square feet on the same site acquired by Microsoft”News report · May 2024 · grade C
Permits and government (8)
- FAA OE/AAA: Determined - No Hazard“PHX 83 NE - Crane - 200 ft AGL - Determined - No Hazard”FAA · Oct. 2026 · grade B
- FAA OE/AAA: Determined - No Hazard“PHX 83 NW - Crane - 200 ft AGL - Determined - No Hazard”FAA · Oct. 2026 · grade B
- FAA OE/AAA: Determined - No Hazard“Microsoft Phx 83 - Crane - 200 ft AGL - Determined - No Hazard”FAA · Oct. 2026 · grade B
- FAA OE/AAA: Determined - No Hazard“PHX 83 SW - Crane - 200 ft AGL - Determined - No Hazard”FAA · Oct. 2026 · grade B
- FAA OE/AAA: Determined - No Hazard“PHX 83 SE - Crane - 200 ft AGL - Determined - No Hazard”FAA · Oct. 2026 · grade B
- site plan: approved (staff report March 16, 2021; Planning Commission recommendation and Council final action)“The applicant is requesting the approval of a site plan for the addition of a second 250,000 square foot data center building at the southeast corner of Olive Avenue and Dysart Road”Local government · March 2021 · grade B
- air permit (backup): generators to be permitted with MCAQD per the approved site plan; issued permit numbers are not published in the sources found“The proposed generators will be permitted with the Maricopa County Air Quality Department (MCAQD) and will be operated in accordance with applicable, MCAQD, State of Arizona, and federal requirements”Local government · March 2021 · grade B
- site plan: filed; planning staff recommended approval 4-0; presented to City Council Dec. 3, 2024“Planning staff recommended the amendment for approval 4-0. The project will be presented to the City Council at the upcoming December 3 meeting”News report · Dec. 2024 · grade C
Site and other (8)
- Announced: July 30, 2019“Microsoft intends to develop the datacenter campuses in El Mirage and Goodyear, Arizona to be among the most sustainably designed and operated in the world”Company · July 2019 · grade A
- Street address: 12901 W Olive Avenue, El Mirage, AZ 85335“Parcel(s): 501-46-854 Address: 12901 W. Olive Avenue, El Mirage, Arizona 85335”Local government · March 2021 · grade B
- Site acreage: 150 acres“Land Area: 6,534,000 sf. ft. (150.0 ac.)”Local government · March 2021 · grade B
- County code: 04013Measured on OpenStreetMap map data.
- Campus name: Microsoft El Mirage campus“Microsoft has requested a site plan amendment for its collection of data center facilities at 12901 W Olive Avenue in the El Mirage area”News report · Dec. 2024 · grade C
- Building sq ft phx83: 245500 sq ft“The amendment covers plans to build a new facility, known as PHX-83, that will total 245,500 sq ft (22,808 sqm)”News report · Dec. 2024 · grade C
- Microsoft launched the West US 3 Azure region in June 2021 and the first El Mirage building (PHX-80) launched in 2021; contemporaneous reporting (Data Center Knowledge, Jun 15, 2021) puts the region's ribbon-cutting at t“Microsoft launched its West US 3 Azure cloud region – based in Phoenix – in June 2021”News report · Dec. 2024 · grade C
- In service date: 2021“Microsoft launched its West US 3 Azure cloud region - based in Phoenix - in June 2021. The first building at the site launched in 2021”News report · June 2021 · grade C
Imagery and records: Satellite imagery: Sentinel-2 (ESA Copernicus).