Original research
Heat and hot water violations turn sharply higher every October.
New York City's heat season starts October 1. HPD's heat and hot water violations, measured by month across every year in our working copy of the record (July 30, 2023 through August 27, 2026), turn sharply at that date. October runs 105.5% above September. January, the peak month, runs 5.8 times the September floor. The rise coincides with the start of heat season. On its own, this pattern does not show that the season causes it.
Violations by calendar month, all years 2023 through August 27, 2026 combined. September 5,070, October 10,419, January 29,276 (the peak).
The single largest one-month jump is Sep-to-Oct itself, +105.5%, right at the heat-season start date. The climb continues past it at a decelerating rate: Oct-to-Nov +82.4%, Nov-to-Dec +28.3%, Dec-to-Jan +20.0% to the peak. A step on October 1, then a longer, slower climb to January.
The October turn, year by year
A pooled average across every year on record can be carried by one unusual winter. Broken out one calendar year at a time, September against October, that is not what happened here.
| Year | September | October | October vs. September |
|---|---|---|---|
| 2023 | 1,702 | 3,461 | +103.3% |
| 2024 | 1,614 | 3,015 | +86.8% |
| 2025 | 1,754 | 3,943 | +124.8% |
October ran above September in every one of the 3 complete years on record, not just in the pooled average: 2023 (+103.3%), 2024 (+86.8%), 2025 (+124.8%).
The control group: categories with no seasonal mechanism
Vermin, water leaks, and electrical conditions have no reason to turn with the heat-season calendar the way a heat or hot water outage does. Measured the same way, September against October, all three:
| Category | September | October | Change |
|---|---|---|---|
| Heat and hot water | 5,070 | 10,419 | +105.5% |
| Vermin and pests | 19,070 | 20,494 | +7.5% |
| Water leaks | 17,173 | 18,883 | +10.0% |
| Electrical | 4,475 | 4,513 | +0.8% |
None of the three has a seasonal mechanism. All three stay close to flat from September to October (vermin and pests +7.5%, water leaks +10.0%, electrical +0.8%), against heat's +105.5%. The October turn is isolated to heat and hot water, not a citywide rise in every violation category that month.
The full monthly series, with its share of the total
Each month's count against the 157,208-violation all-time total, the denominator behind the chart above.
| Month | Violations | Share of all-time total |
|---|---|---|
| Sep | 5,070 | 3.2% |
| Oct | 10,419 | 6.6% |
| Nov | 19,002 | 12.1% |
| Dec | 24,388 | 15.5% |
| Jan | 29,276 | 18.6% |
| Feb | 21,573 | 13.7% |
| Mar | 14,180 | 9.0% |
| Apr | 9,839 | 6.3% |
| May | 6,742 | 4.3% |
| Jun | 5,516 | 3.5% |
| Jul | 5,145 | 3.3% |
| Aug | 6,058 | 3.9% |
The comparison, stated plainly
This compares one calendar month against another inside the same category, never against a different violation type: every HPD Housing Maintenance Code violation whose description matches heat or hot water, all three classes combined, every year on record folded into twelve month buckets. Measured against 2,908,403 total HPD violation rows in our working copy of the record as of August 27, 2026: heat and hot water violations are 5.4% of every violation HPD has on file.
Year over year
The October-to-January climb is not one unusual year averaged into the total; it recurs inside each year on record. 2026 is a partial year, since the record's own working copy runs through August 27, 2026.
| Year | Violations |
|---|---|
| 2023 | 20,329 |
| 2024 | 46,434 |
| 2025 | 54,088 |
| 2026 (partial year) | 36,357 |
Of 157,208 heat and hot water violations on the city's record, 148,225 are Class C, immediately hazardous. Another 6,347 are Class B and 2,635 are Class A.
How this is counted
Violations whose HPD description text matches "heat" or "hot water" (case-insensitive), the same definition already used for the Heat and Hot Water category elsewhere on this site. A text match, not an exact statute classification. Every year on record (2023-present) is summed into the twelve month buckets above; the year-by-year shape behind that sum is broken out below.
157,208 heat and hot water violations, pulled August 29, 2026. What the 24-hour correction standard measures out to in practice is on the accountability page. This season, live, the citywide record, ViolationScout.