A tiger mom agreed to pay an astonishing $1.5 million to a college-admissions consultant to help get her kid into a prestigious prep school and Ivy League college, according to a lawsuit.

The stunning fee was charged by The Ivy Coach, a Manhattan-based “independent education consultant” firm that helps guide anxious parents and their children through the process of getting into elite boarding schools and colleges. The consultant is now suing the mother and daughter for allegedly paying only half the fee.

Vietnamese mom Buoi Thi Bui promised to pay in installments, in exchange for The Ivy Coach’s Bev Taylor helping Bui’s daughter, Vinh Ngoc Dao, apply to seven boarding schools and 22 universities, including Harvard, Princeton and Columbia, according to the lawsuit.

Bui, who lives in Hanoi, and Dao “are amongst the international aristocracy.” They, along with “government leaders, captains of industry, celebrated glitterati and scores of the world’s high net-worth families — and their children,” are among those served by The Ivy Coach, the business claims in Manhattan federal-court papers.

The fee charged Bui is exponentially higher than the industry norm, where independent consultants charge anywhere from $85 to $350 an hour and comprehensive packages range from $850 to $10,000, according to a January survey by the Independent Education Consultants ­Association. The company defended its fees in a February blog post.

“Over the years, many folks have been surprised by our fees. Some have derided us. Some have questioned why our fees aren’t comparable to other private college-counseling firms,” they wrote. “We appreciate that our fees are high . . . The parents of our students appreciate that it is worth investing to help their children earn admission to an outstanding school when they’d otherwise earn admission only to a pretty good school.”

The consultant also boasted of creating jobs. “We bring money and employment opportunities into America,” they wrote. “If only Indiana’s Carrier [the air-conditioning company that shipped jobs overseas] could say the same.”

The $1.5 million fee shocked higher-education experts. “Oh my God. Now that’s chutzpah,” said Brooklyn College and CUNY Grad Center Education Professor David Bloomfield. “I’m trying to wrap my mind around it.

“I mean, it’s legal. But it’s abhorrent and borders on unethical because it’s not clear what value they are adding,” he added.

The Ivy Coach’s lawyer declined to comment on the eye-popping $1.5 million fee.

“All they ask . . . is payment of the agreed-upon amount for their intellectual know-how and efforts,” attorney Silvia Jordan said.

Their services include helping the well-heeled with everything from writing college essays to steering them through admissions interviews, getting letters of recommendation and “guidance as to all other aspects of the admissions process,” The Ivy Coach says in court papers.

The Ivy Coach’s deal with Bui included “helping her daughter find an admissions hook for highly selective colleges,” according to court papers. Bui signed the contract agreeing to pay the $1.5 million regardless of whether her kid was accepted anywhere, The Ivy Coach contends.

The Ivy Coach helped Dao get into the Solebury School in Pennsylvania, a prep school that costs more than $55,000 a year.

Bui made an initial payment to TIC but then sought to delay paying any more until after early-admissions college decisions were made, prompting The Ivy Coach to question whether the mom intended to honor the contract.

Communicating through Dao, the mom swore to “definitely” pay the remaining $750,000 but then blew it off, The Ivy Coach alleges. A social-media post suggests that Dao got early admission into Dartmouth, one of the universities on her list, according to the suit. The mom and daughter did not return a message.