Heat season in New York City: the rules and the numbers.

Heat season runs October 1 through May 31. During the day, from 6 a.m. to 10 p.m., the city's Housing Maintenance Code requires an indoor temperature of at least 68°F whenever it drops below 55°F outside. Overnight, from 10 p.m. to 6 a.m., the requirement is 62°F regardless of the outside temperature. Hot water is not seasonal: HPD requires at least 120°F at every fixture, year round. A hot water complaint filed in July follows the same 311-to-inspection path as one filed in January. The heat requirement sits at Admin. Code Section 27-2029; the hot water requirement sits at Section 27-2031. HPD enforces both through inspection, usually after a 311 complaint.

By class

HPD sorts every heat and hot water violation into one of three classes. Each class carries its own correction window, and the window sets how urgently an owner must act.

Class C accounts for 94.2% of all heat and hot water violations HPD issues. What happens to those Class C violations after they are issued is on the heat certification page.

The monthly pattern, in full

Violations follow the season. Here is the shape across every year we hold, first as a chart and then as a table.

All years 2023 through September 24, 2026 combined (our copy begins August 7, 2023). October runs 57.2% above September. January, the peak, runs 4.4 times the September floor. The full measurement behind those two figures is on the seasonal-spike page.

By borough

Heat and hot water violations over the last three years, counted from the city's data on September 29, 2026, do not split evenly by borough.

Bronx carries the most at 55,281. Staten Island carries the fewest at 2,394. Each borough's own page carries this figure alongside its other categories: Bronx, Brooklyn, Manhattan, Queens, Staten Island.

After certification

Since August 7, 2023, HPD has recorded 149,537 Class C heat and hot water violations, and 48.9% have ever been certified corrected. The median time to certification is 9 days, and 93.1% of certifications met the notice's certify-by date. The 90th percentile is 15 days. The remaining 76,488 have not been certified at all, and 19,631 of those have sat open more than a year. The full measurement, set against the certify-by date on the notice, is on the heat certification page.

What a tenant does

A tenant without heat or hot water can call 311 to file a complaint. HPD schedules an inspection. If an inspector confirms the condition, HPD issues a violation, and from then on it is public. A photograph and the date of the complaint help if a second call is needed. Once a violation is issued, the case is searchable on HPD Online by address. If the condition is still not corrected, the tenant can call 311 again to request a reinspection.

What an owner does

An owner corrects the condition and certifies the correction with HPD. If the certify-by date passes with no accepted certification, the status moves to Not Complied With. Certification is filed directly with HPD once the repair is complete, and HPD then mails the tenant a CIV14 letter asking whether the repair was made.

Both research pages behind these figures go further: the seasonal spike, measured precisely, and heat certification, measured against the certify-by date. By borough, citywide counts, ViolationScout. What to do about a heat violation: the heat guide.