Domestic violence is fueling the city’s homeless crisis — and forcing taxpayers to foot the bill for affected families to stay in potentially dangerous hotels, a new report from City Comptroller Scott Stringer revealed Monday.

Two out of every five families in New York’s maligned shelter system were forced from their homes by abusive relationships, Stringer’s office found. That’s a 44 percent increase over five years.

Domestic abuse is now the single largest cause of homelessness in the city.

More than 7,000 kids — most younger than 6 — were also made homeless when their moms fled their abusers, according to Stringer’s analysis.

As a result, the city’s use of hotels to house family victims of domestic violence skyrocketed.

The number of families placed in hotel shelters has increased exponentially over the last five years, despite city inspectors finding wretched conditions at the facilities.

Nearly 1,000 families were placed there in 2018, up from just two in 2014, Stringer’s study found.

“They put families with children impacted by domestic violence in these terrible hotels,” Stringer said at a press conference, where he released the report. “Domestic violence survivors and their children need permanent and affordable housing, not motel rooms with no kitchen and no security.”

Stringer’s report — which he called the “most comprehensive analysis to date” on the issue — doesn’t address the cost of all the hotel rooms, but statistics on his Web site say that city officials “recently entered into $369 million in annual contracts with Children’s Community Services Inc. to shelter homeless New Yorkers in commercial hotel rooms over the next three years” and that the city was “anticipating nearly $1.1 billion in expenditures for commercial hotel rooms alone.”

A series of stories in The Post exposed unsafe conditions at hotels used for shelter by CCS and another nonprofit, the politically-wired Acacia Network.

City Hall spokesman Avery Cohen said, “This administration has funded a dramatic expansion of resources to guarantee survivors receive the immediate help they need, including 300 more emergency beds.”

“We will review the report to ensure we are doing everything we can to make our city safe for everyone at all times,” Cohen added.