These thrones aren’t made of gold — but they oughta be.

A pilot project to buy and install a single high-tech toilet in a park in each of the five boroughs could cost New York City taxpayers a whopping $5.3 million — despite the quintet of commodes selling for less than a million dollars in total.

One of the Portland Loo brand toilets, which cost about $185,000 a pop, is set to be placed in each of the five parks to start a long-awaited project to bring relief to Big Apple residents, city officials said Monday. 

But the total project — including the loos’ installation in a city mired in bureaucratic red tape and head-spinning building regulations — is expected to balloon the total price tag to more than $5 million, or an average of over a million dollars per potty.

A Parks Department rep blamed the massive bill at least partly on installation costs.  

“One major consideration is that these locations were intentionally chosen to bring new bathrooms to areas that didn’t have one previously, so they will require brand new utility runs to provide water and electrical service to the loos,’’ the spokesman wrote in an e-mail. 

“Total cost will also include site considerations such as preparation work, laying a foundation, fencing etc.”

And the city’s notoriously complex regulations, including those involving such prefabricated structures, only drive costs up with the delays they frequently cause.

The portable bathroom manufacturer, Madden Fabrication, told TheCity.nyc, which first reported on the bank-breaking bathrooms Monday, that trying to navigate through New York City bureaucracy to get approvals has been a nightmare like no other.

“I built 180 of these, from Portland to Alaska to Miami, and I’ve never had this certification problem,” sales manager Evan Madden said to the outlet, which first reported on the five costly loos.

“New York City has been the most difficult to have a permit approved for.”

Some residents of Manhattan’s East Harlem, where Thomas Jefferson Park is among those set to get one of the new toilets, said the whole thing stinks.

“They can spend $1 million a lot better in this neighborhood than building a toilet,’’ local Mike Gran, 32, told The Post.

“It’s ridiculous. It makes no sense,’’ he said of the eye-popping expenditure.

“They could spend a quarter of that money cleaning the porta-potties we already have and spend the rest on some pull-up bars, new rims for the basketball court and nets for the tennis.”

Another resident, Sherman Walker, 83, said the $1 million figure was eye-watering — but so was the stench coming from the existing porta-potties.

“One million dollars is a lot of money. It’s more money than I’ll ever see. Just for a toilet?” Walker said. “But if the other boroughs are getting it, why shouldn’t we?

“The porta-potties here are the nastiest things you’ve ever seen in your life.

“People miss the hole. They stand and dump. All you can do is take a leak, but you have to hold your nose to do that.”

The city Parks Department still needs to get several approvals, including from local community boards, to move ahead with the plan, which has been several years in the making.

The toilets’ manufacturer told The City that it got an angry call from a Big Apple official in February 2022 demanding to know why the company hadn’t provided any loos yet. 

The company rep responded that was because no one from the city had actually ordered them, the outlet reported.

The portable potties were actually proposed as a cost-saving measure, considering a more elaborate, larger “comfort station’’ runs between $5 million and $10 million to build, The City said.

Then-Mayor Bill de Blasio decried the situation in 2019, saying something “has to change” if it costs that much and takes so long to bring bathrooms to parks, according to The City.

The Parks rep said in his e-mail to The Post that the agency “has taken several steps to reduce the cost of new comfort stations including standardizing the design, eliminating costly materials, eliminating custom materials, limiting utility runs, and limiting landscaping work.

“We also met with contractors directly to understand the issues that come up during construction that we might be able to solve for through our design process. We continue to explore alternative structures such as the Portland Loo and other pre-fabricated facilities.

“We anticipate finishing design this year, and then moving into procurement.”

The city parks set to get the new free-standing loos, ideally as soon as summer 2024, are: Thomas Jefferson Park; Brooklyn’s Irving Square Park in Bushwick; the Hoyt Playground in Astoria, Queens; the Joyce Kilmer Park near Yankee Stadium in the Bronx, and the Father Macris Park in Graniteville on Staten Island.

“We are installing Portland Loos in one park in each borough, in areas specifically chosen because they did not previously have bathrooms,’’ the Parks official wrote.

“This is a pilot to determine the feasibility of using this model in the future as an economical solution to building bathrooms in parks.”

The Portland Loos are already used in places such as Hoboken, NJ, and Shelter Island off Long Island, the company’s website says.

Residents near Thompkins Square Park in the East Village of Manhattan would likely welcome any help.

As The Post reported Saturday, people have been increasingly defecating and peeing around the park and between nearby cars since a broken pipe and malfunctioning boiler in the basement of the field house forced the public restrooms to close in November.