609 I ST NW
Office · Washington · 20001
At a glance
609 I ST NW in Washington, DC is listed on the Washington, DC property roll as “Office”, SSL 04520837. The roll records 3,126 sq ft of building area, a 1890 build year and an assessed value of $699,630. It last sold for $638,124 in Jul 2017 on a deed covering 2 parcels. 1 active business locations at this address appear in public records.
Recorded transfers — county roll + state sale file
Sale history
The most recent transfer covered 2 parcels. The price shown is the whole transaction, not this parcel alone, so any per-square-foot figure is measured across everything the deed conveyed. The county record carries no multi-parcel flag for it; the parcels were identified by their identical price, date and ZIP.
| Recorded | Price | Qualification | Source | Instrument |
|---|---|---|---|---|
| Jul 2017 | $638,124 | not rated | County roll | — |
Prices are the consideration recorded in Washington, DC's public property records. Where a qualification code exists it is the assessor's judgement of whether a transfer was arm's length; transfers without one appear unrated rather than assumed clean. Whether a building is on the market today, and at what price, is not a public record and is not shown here — asking prices, listings and lease terms live in private commercial databases.
Public record — 1 matched business locations
Tenants & business locations
| Company | Suite / floor | Since | Source | Match |
|---|---|---|---|---|
| SQUARE 452 TOWNHOUSE, LLC | — | Mar 2025 | DC business licence | folio match · high |
Washington, DC assessment roll
Parcel record
| Field | Value |
|---|---|
| SSL | 04520837 |
| Site address | 609 I ST NW |
| Land use (DOR) | 051 — Office |
| Building area (actual) | 3,126 sq ft |
| Floors / units / buildings | — / — / — |
| Lot size | 1,184 sq ft |
| Year built | 1890 |
| Zoning (primary) | — |
| Land value | — |
| Building value | — |
| Total assessed value | $699,630 |
Recorded owner (assessment roll)
SQUARE 452 TOWNHOUSE LLC
GOULD PROPERTY COMPANY
Owner mailing address: 1725 DESALES ST NW STE 900, WASHINGTON, DC, 20036
The owner is on site.A business-tax receipt at this address is held in the owner's own name, so the public record shows an owner-occupier rather than a landlord letting the space.
5 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
- 609 I ST NW
- City
- Washington
- ZIP
- 20001
Within ~650 m
Nearby office buildings
No other office parcels within ~650 m.
How does 609 I ST NW compare with other Washington office buildings?
At 3,126 sq ft, 609 I ST NW is less than a tenth 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 $224 per square foot of building area, against $370 across all office floor area on the roll.
The last recorded sale priced it at $153 per square foot across the parcels conveyed.
Does the owner of 609 I ST NW hold other Washington office property?
SQUARE 452 TOWNHOUSE LLC also holds a business-tax receipt at this address, so the public record shows an owner-occupier rather than a landlord letting the space.
5 Washington office properties (5 parcels, 388.3K sq ft) are recorded to 4 owner entities sharing this parcel's tax-bill mailing address. A shared mailing address is evidence of common ownership, not proof of it.
What has happened at 609 I ST NW recently?
1 recorded transfer is on file for this parcel, the latest dated Jul 2017.
What does “Office” mean for this parcel?
The Washington, DC roll classifies SSL 04520837 as “Office” (use code 051). 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 609 I ST NW?
The recorded owner on the Washington, DC assessment roll (current) is SQUARE 452 TOWNHOUSE LLC, GOULD PROPERTY COMPANY. Owner mailing address on file: 1725 DESALES ST NW STE 900, WASHINGTON, DC, 20036.
What companies have offices at 609 I ST NW?
1 active business locations at this building appear in Washington, DC public records, including SQUARE 452 TOWNHOUSE, LLC. Public records under-count tenants that don't hold a local receipt or register the address.
How big is 609 I ST NW?
The Washington, DC roll records 3,126 sq ft of building area, a build year of 1890. It sits on a 1,184 sq ft lot.
What is the assessed value of 609 I ST NW?
$699,630 on the Washington, DC roll. Assessed values are taxable-roll figures, not market prices.
When did 609 I ST NW last sell?
The last recorded transfer was in Jul 2017 for $638,124, on one deed conveying 2 parcels ($153 per square foot).
What is the SSL for 609 I ST NW?
SSL 04520837, site address 609 I ST NW, Washington. It is the key to look the parcel up in the Integrated Tax System public extract (Washington, DC).
More around 609 I ST NW
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 04520837.
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, “609 I ST NW, Washington, DC (SSL 04520837)”, https://buildingcensus.com/offices/dc/office-building-dd9fadb4 (data as of September 20, 2026).