First, the geography problem#
"Ashburn" is a region in conversation and a town on a contract. The buildings sit in different counties with different utilities, taxes and power limits. That changes what you can get and when.
Below, every building carries the town it's really in. Shortlist on the town, not the nickname.
Who runs data centers in Northern Virginia#
Checked against the providers' own material on August 26, 2026. Two things to know before you read the tables:
- Most power figures are missing because nobody publishes them. Digital Realty and CoreSite don't. Where you see megawatts, the provider published them.
- Some providers show as one grouped row. Where the codes never resolve to named buildings, we list them together rather than guess. Equinix itself says several of its codes can sit in one building.
Ashburn itself: Loudoun County's Data Center Alley#
| Provider | Site | Address | Published size | Worth knowing |
|---|---|---|---|---|
| Equinix | DC1–DC6, DC10–DC15, DC21, DC22 | Ashburn (several buildings, Data Center Alley) | Not published per building | GROUPED ROW: fourteen codes. Equinix's biggest campus in the Americas. AWS private connection confirmed for the metro. |
| Digital Realty | ACC4–ACC7 | Hastings Dr, Chilum Pl, Gresham Dr, Ashburn | 262,000–446,000 sq ft each | The Digital Loudoun campus. Big buildings aimed at large deployments (our read, from size and history). No power figures. |
| Digital Realty | IAD12, IAD14, IAD24 | Devin Shafron Dr, Ashburn | 103,500–149,500 sq ft each | Smaller buildings that suit rack-and-cage buyers and network-heavy setups (our read). |
| Digital Realty | IAD35–IAD40 | Digital Loudoun Plaza and Round Table Plaza, Ashburn | 166,000–1,013,500 sq ft | IAD39, at 1,013,500 sq ft, is the biggest single building on this page. |
| Csquare | IAD4 | Ashburn (street address not published) | 57,927 sq ft · 35.8 MW | Csquare's only building in Ashburn itself. See the closure note below. |
| Cologix | ASH1, ASH2 | Beaumeade Circle, Ashburn | Not published | UNRESOLVED. Both codes are on Cologix's live directory, but a February 2026 release describes a new 85 MW build on fresh land. Ask which you're being quoted. |
| DataBank | IAD1 | Ashburn (address not published) | Not published | No size, power or address published. Cloud access runs through a partner, not in the building. |
Sterling and Dulles#
| Provider | Site | Location | Published size | Worth knowing |
|---|---|---|---|---|
| Csquare | IAD1 | Sterling (about 7 mi from Dulles) | 141,621 sq ft · 143.2 MW | The most published power of any Northern Virginia building in our directory. |
| Csquare | IAD2 | Sterling (Dulles corridor) | 48,169 sq ft · 35.8 MW | Sterling, not Ashburn. |
| Csquare | IAD3 | Dulles (about 4 mi from the airport) | 21,643 sq ft · 23.9 MW | Dulles, not Ashburn. |
| Digital Realty | IAD44 | 43704 Efficiency Drive, Sterling | 648,500 sq ft | Part of the Digital Dulles campus. Sterling, not Ashburn. |
| CyrusOne | NVA1–NVA9 (Sterling campus) | Sterling (addresses not published) | Not published | GROUPED ROW: nine codes, nothing published about any of them. Built for large deployments, with no rate card. |
Reston: where CoreSite actually is#
| Provider | Site | Address | Published size | Worth knowing |
|---|---|---|---|---|
| CoreSite | VA1 | 12100 Sunrise Valley Drive, Reston | 261,000+ sq ft | CoreSite has no Ashburn building. Its Any2East and Community IX peering exchanges cover the campus. |
| CoreSite | VA2 | 12098 Sunrise Valley Drive, Reston | 192,000+ sq ft | Same campus as VA1 and VA3. |
| CoreSite | VA3 | 12369 Sunrise Valley Drive, Reston | 244,000+ sq ft | The one building-level cloud on-ramp confirmed in this market: 400G AWS Direct Connect, January 2026. |
| Digital Realty | VA3 | 1780 Business Center Drive, Reston | 256,000 sq ft | Also called VA3, also in Reston, different building. Two providers, one label. |
Manassas: federal-grade, and a different market#
Iron Mountain runs a 142-acre campus in Manassas, about thirty miles from Ashburn on a different power grid. It's where the region's strongest security and compliance setup sits.
| Site | Published size | Sold as | Worth knowing |
|---|---|---|---|
| VA-1 | 167,958 sq ft · 12.4 MW | Racks and cages | Secure government rooms and cleared staff. Its federal networks aren't commercial cloud connections. |
| VA-2 | 221,578 sq ft · 24 MW | Racks and cages | Manassas campus. |
| VA-3 | 165,000+ sq ft · ~96 MW across two halls | Large dedicated space | The most power in one Manassas building. |
| VA-4 | Not published | Racks and cages (our assumption) | 11600 Hayden Rd. Often missing from directories because nothing's published. |
| VA-5 | 165,000+ sq ft · 40 MW | Large dedicated space | Provider-stated. |
| VA-6 | 230,000 sq ft · 32 MW | Large dedicated space | Opened Q3 2025. Directories haven't caught up, so don't read its absence there as a no. |
Herndon#
365 Data Centers has a Herndon building. It has no direct AWS, Azure or Google connection in any building, so cloud runs through a partner. Its compliance reports date to 2015–16, so ask for current ones.
What we left off, and why#
- phoenixNAP's Ashburn site rents servers, not space. Directories count it anyway.
- Expedient has no Ashburn building. It peers there, and that isn't the same thing.
Networks and cloud connections#
This is the most connected data center market in the world. Carrier choice is rarely your problem here. Which building you're in is, because the campuses spread across four towns.
Equinix's Ashburn campus has AWS Direct Connect confirmed at the metro level. Its Azure, Google and Oracle claims are network-wide marketing, not a named building.
CoreSite's peering exchanges cover the campus, not each building. If you depend on them, confirm it for the building you're quoted.
Power and the Loudoun squeeze#
Loudoun County is the most power-constrained data center market in North America. That's why providers buy land in Ashburn but build in Manassas, Sterling and further out.
- New capacity takes a long time, and the utility sets the clock.
- Room to grow next to you is scarce. Lock it in when you sign.
- Much of the new space is outside Loudoun, around Manassas and the Dulles corridor.
If you need Northern Virginia, not Ashburn specifically, say so. It opens up far more options.
When Northern Virginia is right for you, and when it isn't#
It fits when#
- You need the most network and peering choice on earth. Nowhere else comes close.
- You want to sit close to East Coast cloud, especially AWS's biggest region, over a private line.
- Your work is federal or close to it. Manassas's secure rooms and cleared staff are rare anywhere.
- You need a very large block of space. Some buildings here top a million square feet.
It doesn't fit when#
- You're watching cost and won't use the network depth. You'd be paying for someone else's needs.
- You'll need a lot more power in Loudoun soon. That's the market's tightest limit.
- You want distance from your other East Coast sites. A lot of the East already sits here.
- You need a handful of racks and nothing more. A regional city will usually fight harder for you.
When a big name is the right call#
- Equinix Ashburn when network density is what you're buying.
- Digital Realty for scale, or one contract across several cities.
- CoreSite Reston for hybrid cloud across US cities, and VA3 when an in-building AWS connection is worth paying for.
Big names earn their place here more than most places. The real mistake is shortlisting on "Ashburn" and missing that half your list is in other towns.
What data center space costs in Northern Virginia#
No provider here publishes a price list. Every price is a quote. Here's why we don't publish per-provider numbers.
For a rough sense, asking rates averaged around $196 per kW per month for 250–500 kW across North America in the second half of 2025. Vacancy sat at a record-low 1.6%. Northern Virginia is at the tight end, so the move-in date often decides things before price does.
Bid the same project in Ashburn, Sterling and Manassas. You'll often get different prices and dates. And push for room to grow at signing, because it's worth more here than almost anywhere.
Common questions#
Who are the data center providers in Ashburn, Virginia?#
Is Ashburn the same as Northern Virginia for data centers?#
Why is Ashburn so short on data center power?#
Which Northern Virginia data centers have a confirmed AWS Direct Connect on-ramp?#
Who has space? Here's how you find out#
This page can't tell you who has space today. Every figure above describes a building, not what's free. Here, that changes faster than anywhere.
The real answer comes from asking every provider that fits, at once, about your project. Clectiv AI does that for you, across Ashburn, Sterling, Reston and Manassas in one go.