Tonight's the night to set your clocks back one hour.
Like 47 other states, Massachusetts will "fall back" one hour at 2 a.m. Sunday, when daylight saving time ends and the state moves back to Eastern Standard Time.
The only states that do not observe daylight saving time are Hawaii and most of Arizona.
Fire officials and FEMA also urge people to use the semi-annual clock changing exercise as a reminder to remove and replace batteries for smoke detectors, carbon monoxide detectors and evacuation flashlights.
While changing batteries be sure to check that the device has not passed any expiration date, and clearing dust from slots or sensors, the agencies said.