The surge in deaths in New York and New Jersey from COVID-19 is causing a backup at area crematories, which could mean families may wait 10 days or more before being able to say goodbye to their loved ones.

One Brooklyn funeral director told The Post he couldn’t get a spot at the crematory at Green-Wood Cemetery until April 14, even though it is handling up to 20 bodies per day. At Rosehill Crematory in Linden, New Jersey, used by a number of city funeral homes, there’s also a several day backup.

It’s a problem at some cemeteries, too.

St. John’s in Queens is booked solid for burials. John Vincent Scalia, who owns a namesake funeral home on Staten Island, said he was told last week the soonest he could hold a burial at the vast Catholic cemetery in Middle Village was April 12. Moravian Cemetery on Staten Island was also scheduling for April 12, while at St. Charles Cemetery in Farmingdale, one of the largest Catholic cemeteries on Long Island, the next available burial date was April 14, Scalia said.

“I’ve never seen anything like this,” said Scalia, who has handled 19 coronavirus cases in the past few weeks, and estimated his volume is about 25% to 35% higher than normal. “I’ve experienced volume — we handled 50 World Trade Center funerals — but I’ve never been through anything like this.”

The city’s death toll from the novel coronavirus reached 1,905 Saturday morning, just 21 days after the Big Apple’s first COVID-related death was recorded at Wyckoff Heights Medical Center in Brooklyn. City records showed 38 people died overnight. Statewide, 630 people died from Friday to Saturday.

The grim toll is expected to keep climbing.

Gov. Andrew Cuomo said Saturday morning the “apex,” or top of the state’s coronavirus cases arc, is expected within the next four to eight days. But deaths will continue for some time after the number of confirmed cases, now at 63,306 in the city, stops rising.

While most of the attention during the crisis has been on the desperate need for protective equipment for the city’s embattled health care workers and on creating enough hospital beds to handle the surge, the deadly bug is also filling the city’s morgues.

Regulators are allowing city crematories to operate around the clock to handle the overwhelming need, The Wall Street Journal reported. Federal and local agencies have sent about 130 refrigerated trucks to serve as temporary morgues for Brooklyn Hospital Center and other facilities around the state.

Cremation has been increasing in recent years, but with the spike in coronavirus cases and the inability to have normal wakes and funerals, the numbers have gone up sharply since the crisis began. “We’ve never seen anything close to this,” the Brooklyn funeral director said.

Dennis Warner, general manager of St. Michael’s Cemetery in Queens, said about half the cremations at its All Souls Crematory are for people who died of coronavirus-related causes. It’s now scheduling up to 24 cremations a day, up from just eight before the pandemic.

The volume and coronavirus-related precautions mean most crematories are now accepting only direct cremations, with no family members present and no chapel service.

Scalia said he is still conducting wakes and funerals, but is only able to allow 10 people to attend a service, limited to immediate family members for two hours.

“We’re doing everything we can as normal as we can,” he said. Noting that most family members cannot be with their loved ones suffering from COVID-19 when they are in the hospital, the services take on extra meaning for survivors. “It’s important for these people to have closure,” he said.