More than 100 days ago, buildings across New York shut their doors and companies sent their workers home. As the coronavirus pandemic swept across the city, lockdown orders left offices dormant, stores shuttered and streets and sidewalks all but abandoned.

On Monday, two weeks after it began easing restrictions, New York City marked another major milestone when it entered a much larger reopening phase, allowing thousands of offices to welcome back employees for the first time since March.

Yet with offices required to limit their maximum capacity and to ensure distance between workers, the number of those returning to work appeared to be a fraction of those that once jostled elbows on crowded subways and packed into high-rise elevators.

Midtown Manhattan'daki insan kaynaklarında çalışan 100 yaşındaki Kiki Boyzuick, “Yüzde 45 normal olmasa da bir nevi normale dönmek güzel” dedi.

On Monday morning, a time when Midtown would typically be crammed with workers, the sidewalks remained largely vacant and the subway cars were relatively empty.

Still, this step toward normalcy, the city’s broadest yet, will pose a major test for efforts to keep the coronavirus at bay, with hundreds of thousands of people projected to return to jobs that keep them in enclosed spaces for hours at a time.

Yet while the positive test rate in the city now hovers yaklaşık 1 yüzde, down significantly from about 60 percent in early April, many companies have decided to not bring workers back for months, if not longer.

Mayor Bill de Blasio estimated that as many as 300,000 people would return to their workplaces this week.

“Phase 1 was a big deal,” Mr. de Blasio said at a news briefing. “But Phase 2 is really a giant step for this city. This is where most of our economy is.”

Ofislerin yanı sıra, yeniden açma planı açık havada yemek yemeye, bazı mağaza içi alışverişlere ve ayrıca kuaför salonlarının, berberlerin ve emlak firmalarının çalışmalarına yeniden başlamasına izin veriyor.

In a survey conducted this month by the Partnership for New York City, an influential business group, respondents from 60 companies with Manhattan offices predicted that only 10 percent of their employees would return by Aug. 15.

Several major media and technology companies with Manhattan offices had already extended their work-from-home policies through the summer. Others have said employees can work remotely through the end of the year.

JPMorgan Chase, one of the city’s largest commercial tenants, said it would not send employees back to their offices this week and had not set a return date. Other financial services firms, like Goldman Sachs, anticipated that a small number of employees would return to their offices, but said that most workers would not come back until well into next year.

Those returning found significantly different workplaces awaiting them.

“It’s not going to feel normal to be in the office,” said Ciara Lakhani, the chief people officer of Dashlane, a software company with about 100 employees in New York. “You can’t socialize the same way, you can’t really attend meetings in person, so people need to understand that we’re not getting back to any sense of normalcy.”

Worried about a surge of virus cases in states that moved more quickly to reopen, New York officials are requiring that strict social-distancing guidelines remain in place.

More than 100 cases per day of the virus are still being reported in New York, according to city data. A contact-tracing program that is supposed to help track the spread of the virus as the city reopens has gotten off to a slow start.

Several landlords of commercial buildings said they had been preparing for months to reopen by implementing new safety and cleaning protocols.

Husein Sonara, the chief operating officer at the Sapir Organization, which manages two properties in Midtown Manhattan, said his company had put markers on sidewalks outside its buildings, in the hallways inside and in elevators so workers can maintain social distancing.

Ken Fisher, a partner at Fisher Brothers, which owns five office towers in Midtown, said his buildings would use thermal scanners to check the temperatures of everyone who entered. Hand sanitizer stations would be placed in all public areas, and only four people at a time would be allowed in the elevators.

To minimize contact on high-touch surfaces, the company implemented a Bluetooth-based system that allows people to enter buildings without touching doors or keypads.

As more businesses call employees back to work, Mr. Fisher’s company expected to recalibrate its procedures.

“We’re calling Monday kind of a soft opening,” he said, “because we don’t anticipate every tenant, obviously, coming back all at once.”

Despite the public health concerns and all the necessary precautions, several business owners and workers said they were eager to return to their desks.

“Some people though have told us, ‘Just to be able to see the plants in the office or to feel like I commute, that’s going to help me personally and mentally,’” Ms. Lakhani, of Dashlane, said of her employees. “And we get that.”

Charles de Montebello, who runs an audio-recording studio in Hell’s Kitchen, said that only two of his five recording rooms would be operating this week. That way, he said, he could ensure that people at his business did not need to come in close contact with one another.

Both studios were booked for full-day sessions on Monday.

“It’s been hard to be away and hard to shut my doors and have literally 90 percent of my income evaporate,” Mr. de Montebello said.

In addition to offices, retail outlets — which had been limited to curbside or in-store pickup — can also allow customers back into stores, though at a reduced capacity.

“It feels like it’s the light at the end of a very long tunnel,” said Nancy Bass Wyden, the owner of the well-known Strand Bookstore in Manhattan. “Almost like we’re Rip van Winkle.”

Restaurants can also begin serving meals outdoors, real-estate brokers can show listings, and salons and barbershops can attend to customers who have been without grooming services for months.

The second stage of reopening will also be another major test of how effectively the city’s transportation system, which before the pandemic packed people into enclosed spaces, can safely carry daily commuters.

Yeniden açmanın ilk aşamasında, şehrin metro sistemlerini ve otobüslerini işleten Büyükşehir Ulaşım Otoritesindeki yetkililerden daha fazla bisikletçi toplu taşıma araçlarına geri döndü.

Mayıs ayında transit yetkilileri, otobüslerde günlük bisikletçiliğin ilk aşamada pandemi öncesi seviyelerin - 40 insanın - yüzde 880,000'ına ulaşacağını tahmin etti. Ancak otobüs yolculuğu zaten normal yolcu yükünün yüzde 56'sına ulaştı.

Metroda, günlük binicilik pandemi öncesi seviyelerin yüzde 17'sine yükseldi - MTA'nın ilk projeksiyonlarından iki puan daha yüksek. Transit acentesi, ikinci aşamada bu sayının iki katına çıkarak iki milyona ulaşmasını bekliyor. Salgın öncesinde binicilik beş milyonu aştı.

Riders are already required to wear face masks under an executive order from Gov. Andrew M. Cuomo. While most appeared to follow suit on Monday, not everyone complied.

Nargiz Aziz, a Staten Island resident who commuted to her job near the World Trade Center on Monday, said people stared at her on the train because she was not wearing a face covering.

“It doesn’t let me breathe well, and it’s not comfortable,” Ms. Aziz, 20, said. “It also doesn’t really protect you.”

Reporting was contributed by Jo Corona, Christina Goldbaum and Nate Schweber.