Long Island Expressway (I-495) accidents in Islip, NY

What our records show

The Long Island Expressway (I-495) runs through Islip as one of the 71-mile primary expressways serving Suffolk County, carrying roughly 200,000 vehicles per day. The posted speed limit is 55 mph. The route stretches from Queens Midtown Tunnel (Manhattan) to Riverhead (Suffolk County), with Islip sitting along that spine. Locally, drivers know it as LIE or The Expressway.

Our database has logged 4 incidents on Long Island Expressway within Islip, including 1 moderate cases. No fatalities have been recorded in the incidents we track for this stretch. The most recent report we published involved Left Shoulder Closed After Westbound I-495 Crash in Suffolk County on May 21, 2026. On average, we've seen roughly 4.0 reported crashes per month on this stretch during the period covered by our archive.

Inside Islip, Long Island Expressway intersects with or runs parallel to several other high-volume routes — LIE, Sunrise Highway, Southern State Parkway — so many crashes on this corridor originate at exits and interchanges rather than along open stretches. That pattern matches what we see in the incident reports below, which cluster around entry and exit ramps feeding those surface streets.

Town context matters because accidents here don't unfold in isolation. Islip is home to about 335,543 residents and falls under SCPD 3rd Precinct. Serious injuries from Long Island Expressway crashes are typically triaged to Southside Hospital (Northwell Health). Below you'll find every incident on this stretch we've covered, newest first.