Baltimore network buildings and Anne Arundel campuses need separate shortlists.

What the public evidence can tell you

The public evidence describes two different searches. Baltimore and the BWI corridor have buildings with network listings. Air records at Annapolis Junction, Jessup and Severn name Microsoft and Amazon sites, but do not establish space for another tenant. Begin with the address that fits the requirement, then confirm power and space directly.

Choose the corridor before the operator

Air-register evidence, not a construction schedule

These air-register entries have no filing dates in the collected records. The IBM Annapolis entry is marked Permanently Closed. That status stays visible below; its inclusion in the register total is not evidence of operating inventory or current construction. The Control Data Corp. entry in Woodlawn is marked Operating, but Control Data Corporation was broken up in 1992. Read that name as an old register entry, not a live operator, and confirm who occupies the address today.

Air-register records in the Baltimore-Washington corridor, including Microsoft and Amazon sites in Anne Arundel County and a permanently closed entry at Annapolis. Every figure below is a count of filings we collected ourselves, and every row links to the record it came from.

Operators appearing by name: Amazon Web Services (2), Microsoft (1).

The filings on the record

Collected from EPA ECHO air facility records for Maryland. A permit or air-register entry documents a site or proposed work. It does not establish current construction or available space, and no public filing anywhere discloses what is contractible at a named building. That answer comes from an operator call, which is the part we do by hand. See how we verify capacity.

Check the underlying records

These public entries were checked against our collected data on 24 September 2026. Each link opens its EPA record. A register status does not establish a current commercial offering.

Where network operators list a presence

The following counts are PeeringDB listings. A network listed in more than one building contributes a presence at each; these are not unique regional carrier counts. Multiple registry entries can also refer to the same property. Confirm the required carriers and routes at the exact address.

Who is actually plugged in across Baltimore and the Maryland corridor

A building existing and a building being connected are different facts, and only one of them decides whether your traffic can get where it needs to go cheaply. These figures come from PeeringDB, which the network operators themselves maintain. Any building below can be looked up there by name.

The most connected buildings here

From PeeringDB, which is maintained by the network operators present in these buildings rather than by the landlords, which is what makes it worth more than a directory. Two limits. Entries are voluntary, so a building showing no networks may be single tenant or may simply never have registered. And a network being present says nothing about whether the building has space, power or a price for you: that is still a call.

Facility inventory coverage

Our committed verified-inventory snapshot has no separate coverage for this region. We therefore publish no inventory count or available-space estimate here. Public air and network records remain separate evidence, with their own limits. See what verified building means.

What has been announced in Baltimore and the Maryland corridor

Announcements are not filings. Nobody has to build what they announce, the figure is the one the developer chose to publish, and the date moves. They are here because megawatts are what a requirement is measured in, and because the size of what is coming changes who will take your call. Every figure below links to a published report that states it, and was checked against at least one other independent report before it was written down.

Announced capacity is collected by hand from trade reporting and company statements, and each figure links to the report it came from. It is kept apart from the permit record above and never added to it: one is a document a jurisdiction issued, the other is a plan a company published. Neither is availability.

The proposed scale is reported independently by WMAR and Data Center Dynamics. Both describe a proposal, not delivered capacity.

The Woodlawn start date in the table is out of date. Woodlawn is in Baltimore County, and the county has paused data center approvals. On 22 September 2026 the County Council voted unanimously to extend that moratorium through the end of 2027. While it runs, the county will not issue data center permits or approve related development plans or zoning petitions (CBS Baltimore). The county first passed the moratorium earlier in 2026. Treat the June or July 2026 start as superseded. Do not plan on new Baltimore County supply before 2028.

How to compare an actual requirement

For a requirement tied to Baltimore staff or networks, start with the specific buildings above. Compare larger requirements with Northern Virginia and Frederick County using the same usable power, density and delivery milestones. Do not assume that a nearby hyperscale site is an alternative supplier.

Pricing context. This guide carries no posted list price for this corridor yet. A number here comes from a quote. For the nearest rates we track, see Ashburn colocation pricing. The cost estimator gives an illustrative range based on Ashburn. Use it as a reference point, not a local price.