The thing to remember about hosting an event at Madison Square Garden — like, say, a wedding between a pop star and a football player — is that rent is only a fraction of the equation.
The base line cost of rent, according to industry insiders who have experience hosting events at the venue, is anywhere from $600,000 to $800,000. Artists or other host parties would, of course, negotiate that rate directly with the venue, particularly someone like Ms. Swift who has a longstanding relationship with the Garden and who can draw voluminous publicity to it.
Representatives of the Garden and Ms. Swift didn’t respond to requests for comment.
One industry insider who has experience working with the venue and spoke on the condition of anonymity estimated that it would cost Ms. Swift somewhere between $1.2 million and $1.6 million to book out the Garden for two days. But that’s just to get through the door, the person added, and probably doesn’t include the cost of essentially closing down the venue this week for setup.
“It’s absolutely more than a wedding,” said Jessica Stewart, the vice president of marketing and sales at EMRG Media, a New York City event company that has worked with Fortune 500 companies.
One recent event at the Garden, President Trump’s rally there in 2024, cost $649,867 in rent, campaign expenditure filings show.
Another cost associated with renting out a venue like the Garden is insurance to cover accidents or property damage as well as any other unforeseen disasters. Depending on the scale and size of an event, the Garden could require minimum policy coverage costing north of $10,000, said Erica Maurer, a partner at EMRG Media.
“There’s a lot of levels to this,” Ms. Maurer said, and the costs can fluctuate depending on decorations, number of performances and other factors, she said. Each vendor may have a supplemental policy as well, she said.
But a touring artist like Ms. Swift might already have a pre-existing insurance policy that she could extend to cover the venue over the holiday weekend, the industry insider noted.
There are also miscellaneous costs — lighting, sound, catering, flowers, decorations, labor — which could push the total tab for the wedding up to a very conservative estimate of $10 to $12 million, said Ms. Stewart. Just the audio and visuals component, if there is a show, could reach $1 million, she said.
“It’s literally what we call a ‘venue takeover,’” Ms. Stewart said.
Security would be another large cost. The event is expected to draw A-list celebrities, who will need to get into and out of the event space in Midtown Manhattan over a holiday weekend, when large crowds of fans and curious onlookers are expected to gather.
Then there are the New York City fees for the permit to hold the two-day affair, which is classified by the city as an “extra-large event.”
Those would be likely to cost the couple at least $132,000 based on the rates charged by the city’s permitting office. That does not include the costs for the fees to extend the permit to Saturday, when a tent and other materials will be broken down and taken out of the building, a process that could take until 7 p.m., according to a person with knowledge of the permit approved by the city.
And, while the couple are likely to pay for their own private security, the total costs of public safety for the event probably will climb far higher, records and interviews show.
Hundreds of police officers are expected to patrol outside the Garden, many of them on overtime shifts. (Jessica S. Tisch, the police commissioner, had already ordered officers to work 12-hour shifts to keep an eye on the World Cup, the Fourth of July, Sail 250 and other long-planned events.)
A representative of the Police Department declined to comment on potential costs to the city.
But rough, back-of-the-envelope math by former city officials puts the cost to taxpayers at well over $1 million.
Kenneth Corey, former chief of department, said for such an event, he would deploy a minimum of about 400 officers to safeguard the crowds outside the Garden.
“The building itself is very easy to secure,” Mr. Corey said. But hundreds of officers will be needed on the streets to monitor for threats and control fans, who might be tempted to rush barricades as celebrities enter and leave the Garden. Several blocks around the venue will be closed on Friday to traffic and pedestrians, including portions of Seventh Avenue, records show.
The total cost for just the added police presence in those areas would most likely reach at least $360,000 per day, according to Mr. Corey.
That doesn’t include the costs for medical personnel from the city’s Emergency Medical Services unit, which will also need to be on hand to care for anyone who becomes overheated or dehydrated.
That would be likely to add another $500,000, said Laura Kavanagh, former commissioner of the Fire Department, which oversees emergency medical services.
The whole thing would probably require the same resources the city spends on a parade, Ms. Kavanagh said — though not one of the Macy’s Thanksgiving Day variety.
Maybe a “medium-sized” parade, she said.
Emma G. Fitzsimmons contributed reporting.