New York City motorists will increasingly encounter 15 mph speed limits around schools across the five boroughs, as the Department of Transportation moves ahead with a sweeping expansion that will eventually cover virtually every eligible school location in the city.

NYC DOT announced this week that it has already installed new 15 mph School Slow Zones at more than 200 school locations in 2026, with roughly 800 locations expected to receive the lower limits by the end of the year. The rollout represents the largest expansion to date under Sammy’s Law, which gave New York City greater authority to reduce speed limits on its streets.

The changes will ultimately extend considerably further. City officials say they intend to establish 15 mph limits at every eligible public, private, parochial and charter K-12 school location across the five boroughs by the end of Mayor Zohran Mamdani’s first term.

There are approximately 2,300 eligible school locations housing some 3,200 individual schools, since multiple schools sometimes share the same campus.

For drivers, the result will be a significant proliferation of streets where the familiar citywide 25 mph limit no longer applies. The standard speed limit on most New York City streets remains 25 mph unless signs indicate otherwise.

The city’s plans for 2026 call for converting roughly 700 existing 20 mph School Slow Zones to 15 mph and establishing approximately 100 additional 15 mph zones at schools where the current limit is 25 mph.

Combined with locations that had already received lower limits before this year, city officials said in March that the expansion would bring the overall number of school locations with 15 mph limits to approximately 1,300 by the end of 2026.

The administration says the lower limits are intended to reduce the severity of crashes involving children and other pedestrians. According to DOT, a pedestrian struck by a vehicle traveling 25 mph is more than three times as likely to suffer a serious injury as someone struck at 15 mph.

“Families spoke up after unimaginable loss to fight for Sammy’s Law and deliver our city the power to make our streets safer for New Yorkers,” Mamdani said when the larger rollout was announced earlier this year. “Today’s expansion of Slow Zones for schools across all five boroughs is just the beginning. Lower speeds save lives, and we will use every tool at our disposal to protect our neighbors as they move about our city.”

DOT Commissioner Mike Flynn said the agency is prioritizing areas based on safety data.

“Our school children and their families should feel safe and comfortable as they travel to and from class. Speeding is the leading cause of traffic deaths, and even a small speed reduction can mean the difference between life and death in a crash,” Flynn said. “These speed limit reductions will follow our data-driven Vision Zero approach to deliver the greatest safety impact.”

The lower speed limits will not simply appear overnight. Before implementing a new School Slow Zone, DOT must provide the relevant local community board with a 60-day notice-and-comment period. The agency is determining eligibility and prioritizing individual locations using crash and safety data, along with other planned street projects.

Sammy’s Law, enacted in 2024, gave New York City new authority to reduce speed limits below the longstanding 25 mph citywide standard. The legislation allows the city to establish lower limits on qualifying streets and designated slow zones, although certain roadways are excluded under the state law.

The law was named for 12-year-old Sammy Cohen Eckstein, who was struck and killed by a driver in Brooklyn in 2013. His family subsequently became prominent advocates for giving New York City greater authority to lower vehicle speeds.

The 15 mph signs are only one part of a broader effort to redesign streets surrounding schools.

DOT says it is implementing safety upgrades adjacent to more than 300 schools during 2026. Depending on the location, projects can include redesigned intersections, expanded pedestrian space, safer crossings, speed humps and other physical changes intended to force or encourage motorists to slow down.

The city is also expanding its Open Streets for Schools program. Seventy-seven school Open Streets are launching for the 2026-27 school year, allowing participating schools to temporarily restrict vehicle access during periods such as morning arrival, dismissal, recess and outdoor instruction.

One of the more unusual additions will appear in Tribeca, where DOT plans to install what it describes as New York City’s first gated Open Street outside a school.

A gate will be installed on Clarkson Street between Hudson and Varick streets as part of a larger redesign near City-As-School High School and M.S. 721. The concept was inspired by school streets in Paris that use gates to keep vehicles out during designated periods. The project will also add seating, increase pedestrian space, improve sight lines and crossings, and introduce design elements intended to slow traffic.

Other school-area projects are planned across the five boroughs, including work on Coney Island Avenue near P.S. 889 and M.S. 890 in Brooklyn; portions of Beach Channel Drive and Rockaway Beach Boulevard in Queens; and several Bronx corridors serving more than 10 schools.

The scale of the School Slow Zone program is expected to continue growing after this year.

Under the administration’s current plan, all approximately 2,300 eligible school locations are slated to have 15 mph limits by the end of 2029. Certain schools may not qualify because they are situated on private roads or along roadways exempted by Sammy’s Law, including some multi-lane streets outside Manhattan.

For New York motorists, the practical message is straightforward: drivers accustomed to the city’s 25 mph limit — or even the 20 mph limits previously posted around many schools — will need to pay increasingly close attention to School Slow Zone signs.

With hundreds more 15 mph zones scheduled to appear before the end of 2026 and thousands ultimately planned, 15 mph is set to become a far more common sight on streets surrounding New York City schools.