A Class C violation not certified in 90 days almost never is.
HPD recorded 315,787 Class C violations, the class it treats as immediately hazardous, from August 27, 2023 through September 24, 2024, the stretch of our copy of the record that is still kept up to date and at least two years old. Every one has had at least two years for a certification to arrive. 47.0% have one on file, and 97.8% of those were filed within 90 days of the inspection. Of the violations with no certification by day 90, 1.9% got one at any point after.
Three figures, three denominators
The 97.8% is a share of the 148,452 certifications filed. The 1.9% is a share of the 170,532 violations still uncertified on day 90, of which 3,197 were certified later. The 58,719 still open are part of the 167,335 with no certification at all, which is 53.0% of all 315,787 violations. They answer different questions, and a percentage quoted without its group answers none of them.
The curve, quarter by quarter
Group the same record by the quarter each violation was inspected and the pattern repeats in every quarter. In each quarter followed a year or more, the share certified to date sits at most 1.2 points above the share certified within 90 days. Waiting longer does not move the number. A quarter appears once its last violation is 90 days old.
| Inspected | Class C | Certified within 90 days | Certified to date | Days followed |
|---|---|---|---|---|
| 2023-Q4 | 77,021 | 45.8% | 47.0% | 998 |
| 2024-Q1 | 84,341 | 47.3% | 48.3% | 907 |
| 2024-Q2 | 67,760 | 45.8% | 46.8% | 816 |
| 2024-Q3 | 67,128 | 45.4% | 46.2% | 724 |
| 2024-Q4 | 78,527 | 46.7% | 47.4% | 632 |
| 2025-Q1 | 81,019 | 48.4% | 49.0% | 542 |
| 2025-Q2 | 60,539 | 44.5% | 45.2% | 451 |
| 2025-Q3 | 58,371 | 42.7% | 43.3% | 359 |
| 2025-Q4 | 78,247 | 44.7% | 45.2% | 267 |
| 2026-Q1 | 78,208 | 46.9% | 47.2% | 177 |
Not certified is not the same as open
A violation can close without a certification. Of the 167,335 violations in the two-year group with none on file, HPD's own status field shows 58,719 still open, 35.1%, and 108,616 closed. The uncertified group holds the violations that stay open, and also the ones HPD closed on its own record without a filing.
What a certification is
A certification is the owner's filing that the condition was corrected, dated the day it was filed. It is not HPD's acceptance: HPD later reads some filings as invalid or false and the violation stays open. The median certification in the two-year group was filed 17 days after the inspection. How one is filed, and what it can hold up, is in the certificate of correction guide.
What the pattern means for one building
A Class C violation past 90 days with nothing filed will very likely never see a certification: the record shows no slow tail of late filings. From there it goes one of two ways. HPD closes it without one, as it did for 108,616 of the 167,335 in the two-year group, or it stays open, as 58,719 still are. Correcting the condition and filing the certification is the owner's way to end it on the record. The owner's side of that is on the owners page, and any building's open violations are one search away below.
See what is open on one building.
How this is counted
Every Class C violation in our copy of HPD's violation record (NYC Open Data wvxf-dwi5, all statuses) inside the window our copy still keeps up to date, timed from its inspection date to the date a certification was filed. The mature group is every Class C violation inspected at least 730 days before the record's latest inspection date. Open and closed are the city's own violation status field. A certification dated before its inspection is excluded as a record defect.
Quote this finding
Quote it directly. The sentence below carries its own denominator and date, which is what a fact-checker will ask for:
“Of New York City Class C housing violations followed for two years, 97.8% of the certifications ever filed came within 90 days of the inspection, and 1.9% of the violations uncertified at 90 days were certified later.” ViolationScout, September 26, 2026
Method: every Class C violation in our copy of HPD’s record inspected August 27, 2023 through September 24, 2024, measured from inspection date to the date a certification was filed. Underlying data is NYC Open Data, public and free to verify. We will share the query behind any figure here on request: press@violationscout.com.
Cite this page
ViolationScout, Class C certification: 90 days or never, our working copy of HPD Housing Maintenance Code Violations (NYC Open Data, dataset wvxf-dwi5), frozen at publication and not re-queried on later deploys. Figures cover the record through September 24, 2026 and were read on September 26, 2026. https://violationscout.com/research/class-c-certification-90-days
Every Class C violation in our copy of HPD's violation record (NYC Open Data wvxf-dwi5, all statuses) inside the window our copy still keeps up to date, timed from its inspection date to the date a certification was filed. The mature group is every Class C violation inspected at least 730 days before the record's latest inspection date. Open and closed are the city's own violation status field. A certification dated before its inspection is excluded as a record defect. Source: NYC Open Data. How every figure here is counted: /methodology.
315,787 Class C violations inspected August 27, 2023 through September 24, 2024, pulled September 26, 2026 from a record running through September 24, 2026. The heat and hot water slice of the same record, against the certify-by date on its notice, is on the heat certification page. Research, the citywide record, ViolationScout.
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