JetBlue Airways Corp. said flights are back to regular schedules in New York and will be in Boston by Monday.
Amtrak trains were running on a limited schedule between New York and Boston, after service between the two cities was canceled Saturday.
Regional lines were still working to restore service.
As of Sunday afternoon, Metro-North Railroad service on the New Haven Line was operating between New York City and Stamford, Conn., but remained suspended between Stamford and New Haven, and on branch lines. Train crews were working to clear as much as 4 feet of snow off the tracks.
The Long Island Rail Road was back to "near-normal" weekend schedule on the western portion of most of its lines, New York's Metropolitan Transportation Authority said. But train service in Long Island's Suffolk County, also hit with more than two feet of snow, was suspended.
Most New York City subways and buses were operating on a regular schedule.
The Massachusetts Bay Transportation Authority said service on some subway and bus lines resumed at about 2 p.m., and planned to operate on regular schedules Monday. But the agency said commuters should expect "significant" delays.
Most commuter rail service around Boston should resume by Monday morning, the agency said on its website.
The blizzard also snarled drivers across the Northeast as snow cleanup continued Sunday.