If it's more than six months, the city won't collect its more than 4% income tax, and property values will drop.
But in suburban areas outside New York City, there's been a real estate boom. In Nassau County on Long Island, home sales are up more than 60%.
"If you have two kids and you're in an apartment, it's a lot worse than having a home and having a yard," Douglas Elliman CEO Dottie Herman said.
Related: Moving companies turn customers away as people leave Tri-State in record numbers
Who moved where during COVID-19?
According to the Nassau County Executive Laura Curran, the homes sales have surged due to the pent up demand as showings finally re-opened. But additionally, prices island-wide are up 5%, and 5.55% in Nassau. And along the North Shore, that number jumps to nearly 9%.
"We're also talking with school districts to see what their enrollment looks like," Curran said. "Whether it's going up or down, and what they might need in terms of help."
Experts say millennials are driving the new wave -- those on the older side, in their 30s, with families, but still looking to get out and enjoy eating and shopping.
"And these walkable, vibrant downtowns are a real key to that," Curran said. "That's what young people are really looking for."
Related: Suffolk wants to keep NYC summer tourists who fled coronavirus
But aside from the fear of COVID and the ability to work remotely, officials say the recent surge in gun violence in New York City may be what's sealing the deal.
"Even more fearful of the virus is what they're fearing about safety, with what's gong on in the city," Herman said.
Safety in all forms is the top priority.
Related: LI schools see surge in enrollment as families flee NYC
RELATED: New York, New Jersey, Connecticut out-of-state travelers quarantine list
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