601 E ST NW # B300
Office · Washington · 20049
At a glance
601 E ST NW # B300 in Washington, DC is listed on the Washington, DC property roll as “Office”, SSL 04562018. The roll records 19,798 sq ft of building area and an assessed value of $8,475,300.
Public record — 0 matched business locations
Tenants & business locations
No active business locations at this address appear in the public records ingested so far. That is a statement about the records, not the building: tenants without a county business-tax receipt or a Florida registration at this address are invisible to public data.
Washington, DC assessment roll
Parcel record
| Field | Value |
|---|---|
| SSL | 04562018 |
| Site address | 601 E ST NW # B300 |
| Land use (DOR) | 057 — Office |
| Building area (actual) | 19,798 sq ft |
| Floors / units / buildings | — / — / — |
| Lot size | 2,034 sq ft |
| Year built | — |
| Zoning (primary) | — |
| Land value | — |
| Building value | — |
| Total assessed value | $8,475,300 |
Recorded owner (assessment roll)
PHASE I 456 ASSOCIATES
AARP TAX DEPT RM A1-350
Owner mailing address: 601 E ST NW, WASHINGTON, DC, 20049
33 Washington office properties share this owner mailing address →
Commercial property is usually held one building per entity; a shared mailbox is how the roll reveals a portfolio. It is evidence of common ownership, not proof.
Location
- Address
- 601 E ST NW # B300
- City
- Washington
- ZIP
- 20049
Within ~650 m
Nearby office buildings
No other office parcels within ~650 m.
How does 601 E ST NW # B300 compare with other Washington office buildings?
At 19,798 sq ft, 601 E ST NW # B300 is less than a fifth the size of the average office building on the Washington, DC roll, which comes to 120,450 sq ft across 1,761 buildings.
Its assessed value works out to $428 per square foot of building area, against $370 across all office floor area on the roll.
Does the owner of 601 E ST NW # B300 hold other Washington office property?
33 Washington office properties (33 parcels, 443.1K sq ft) are recorded to 3 owner entities sharing this parcel's tax-bill mailing address. A shared mailing address is evidence of common ownership, not proof of it.
What does “Office” mean for this parcel?
The Washington, DC roll classifies SSL 04562018 as “Office” (use code 057). BuildingCensus includes a parcel in its office census when the roll gives it an office-class use, so the label is the county's, not an inference.
Frequently asked questions
Who owns 601 E ST NW # B300?
The recorded owner on the Washington, DC assessment roll (current) is PHASE I 456 ASSOCIATES, AARP TAX DEPT RM A1-350. Owner mailing address on file: 601 E ST NW, WASHINGTON, DC, 20049.
What companies have offices at 601 E ST NW # B300?
No business locations at this building appear in the public records ingested so far — no licence, tax or registry record currently lists this address; that is a gap in the record, not proof the building is empty.
How big is 601 E ST NW # B300?
The Washington, DC roll records 19,798 sq ft of building area. It sits on a 2,034 sq ft lot.
What is the assessed value of 601 E ST NW # B300?
$8,475,300 on the Washington, DC roll. Assessed values are taxable-roll figures, not market prices.
What is the SSL for 601 E ST NW # B300?
SSL 04562018, site address 601 E ST NW # B300, Washington. It is the key to look the parcel up in the Integrated Tax System public extract (Washington, DC).
More around 601 E ST NW # B300
Everything here comes from public records, and public records go stale. If you know better, say so.
Data provenance — public records only
- Washington, DC — Integrated Tax System public extract (owner names, mailing addresses, assessments), CAMA commercial and daily sales tables, Basic Business Licenses (suite-level premises; the universal catch-all licence was repealed Oct 2025, thinning the roll thereafter), and DOEE energy benchmarking.
Every fact on this page is drawn from the government records above — no listing sites, no scraped platforms, no third-party images. Facts from public records are uncopyrightable; each tenancy row carries its source and match confidence. Records can lag reality — a business-tax receipt or registration at an address is evidence of occupancy, not a lease confirmation.
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Dataset updated . Source: Washington, DC assessment roll, SSL 04562018.
About this data
Source: Integrated Tax System public extract (Washington, DC), as published September 20, 2026. See the methodology for how records are matched, cleaned and scored.
Cite as: BuildingCensus, “601 E ST NW # B300, Washington, DC (SSL 04562018)”, https://buildingcensus.com/offices/dc/office-building-83c407be (data as of September 20, 2026).