Daylight-saving time ends at 2 a.m. on Sunday, November 1. Brian Snyder/Reuters Daylight-saving time in the US ends on Sunday, November 1, 2020 at 2 a.m. That morning, most phones and computers will automatically tick backward one hour, and we'll win an hour more to sleep. But the opposite interruption in the springtime, when we lose an hour of sleep, can kill people: Incidents of heart attacks, strokes, and fatal car accidents all spike around the start of daylight-saving time each year. Visit Business Insider's homepage for more stories. Daylight-saving time is a killer.The annual ritual in which we "gain" an hour of evening light in the summertime by pushing the clocks forward, and then descend into darker evenings by pushing the clocks backward in the fall may seem like a harmless shift.But every year on the Monday after the springtime switch, hospitals report a 24% spike in heart-attack visits around the US.Just a coincidence?