Working moms are the top breadwinners in more than 40 percent of American households with at least one child under 18 — the highest rate in history, researchers said yesterday.

“A couple of years ago, this study would’ve surprised me, but now I know it’s true,” said divorcée Jennifer Santiago, 29, a working Bensonhurst mom of three.

Back in 1960, only 11 percent of child-rearing households were primarily funded by a woman, according to Pew Research Center.

“Women’s roles have changed, marriage rates have declined — the family looks a lot different than it used to,” said Kim Parker, of the Pew Social & Demographic Trends Project.

Andrew Cherlin, a professor of sociology and public policy at Johns Hopkins University, said he hopes the findings will change laws and workplace rules.

“Until we realize that the breadwinner-homemaker marriage will never again be the norm, we won’t provide working parents with the support they need,” he said.