The rates, side by side
Rates are set by D.C. Code §47-813 per $100 of assessed value:
| Tax class | Rate per $100 | On a $500,000 building |
|---|---|---|
| Class 1 — occupied residential | $0.85 | $4,250/yr |
| Class 3 — vacant | $5.00 | $25,000/yr |
| Class 4 — blighted | $10.00 | $50,000/yr |
The difference compounds: every year a $500,000 building sits on Class 3 instead of Class 1 costs an extra $20,750. On Class 4, an extra $45,750.
How a building becomes Class 3 (vacant)
The Department of Buildings (DOB) designates a building vacant based on inspection — boarded or broken windows, no utility activity, accumulated mail, neighbor complaints, or a failed occupancy check. Once designated, the owner must register under the Vacant Building Registration program (D.C. Code §42-3131.05), pay registration fees, and the Office of Tax and Revenue moves the property to the Class 3 rate.
How Class 3 becomes Class 4 (blighted)
Blight is a second, worse determination: DOB finds the vacant building is also unsafe or unsanitary— structural deterioration, fire damage left unrepaired, open access for trespass, serious unabated code violations. Blighted buildings don't qualify for most exemptions, and the rate doubles to $10.00. If your building is trending toward blight (open violations aging past their cure windows), acting before the designation is worth tens of thousands of dollars.
Every path back to Class 1
- Restore occupancy. The durable fix: a tenant or owner-occupant, active utilities, and a DOB inspection confirming occupied status. The vacant designation is removed and OTR reclassifies.
- Contest the designation. If the building was never actually vacant, petition within 15 days of the designation notice. See our guide to the Vacant Building Response Form.
- Claim an exemption. Active construction, active sale or rent listing, probate, pending zoning approval, or documented hardship — each with strict time limits and a 5-year lifetime cap. Details and the full table are in the exemption form guide.
- Cure violations first.Whatever the path, open DOB violations block reclassification. They have to be closed in DOB's system — not just fixed in real life.
The two-agency trap
DOB owns the designation; OTR owns the tax bill. Winning at DOB does not automatically fix the bill — the classification change has to post at OTR, and effective dates depend on where you are in the assessment year. The single most expensive mistake we see is an owner who "fixed it" in March and finds the 5% rate still on their bill in September.