The Bourne Mansion

Book the Bourne Mansion for 2026 and you are booking a Saturday on the campus of a British boarding school. Harrow International School New York opened in Oakdale in September 2025, and the 1897 mansion is its central building. The school states on its own site that weddings and other celebrations will continue to take place throughout the school year. Lessing’s still runs the food. Nobody else in this directory will tell you the first part.

The campus changed hands, and it matters

The 170 acres at 500 Montauk Highway have been a military academy, then a university, and now a school again. La Salle Military Academy took the estate in 1926. St. John’s University bought it in 2001 and ran graduate programs out of Oakdale. Amity Education bought the campus from St. John’s in 2016 for $22.5 million, and Harrow opened there in September 2025 with 18 students in grades six through ten.

Harrow is mid-renovation. The Long Island Press put the project at $100 million, with dormitories arriving in 2026, 2027 and 2028 to house 348 boarders alongside roughly 85 day students. Construction somewhere on 170 acres is not the same as construction beside your ceremony. Ask anyway. Ask about your specific date.

The school’s own page on the mansion is unusually direct: celebrations keep happening through the school year, and the building also hosts the Oakdale Civic Association and the Oakdale Historical Society. That is an owner treating an inherited events business as an obligation rather than a nuisance. Read it as a good sign.

Frederick Bourne, Ernest Flagg, 110 rooms

Frederick Gilbert Bourne ran the Singer Manufacturing Company and built Indian Neck Hall between 1897 and 1900, with Ernest Flagg as architect. Harrow counts 110 rooms. Wikipedia’s entry records it as reputed to be the largest estate on Long Island when it went up. The Georgian bones are original; none of the scale was added later to make the place work as a venue. That is the difference between this and a mansion-styled catering hall, and it is most of what you are paying for.

What it costs, as far as anyone will actually say

Bournemansion.com publishes a starting rate of $119 per person and a $3,000 advance deposit on its private events page, but no minimum. The four packages listed under events and packages (Foundations, Elegance, Grand Affair, Ultimate Diamond) carry a single line of description each and no price. The Grand Reception menu includes unlimited top shelf liquors, a champagne toast, the bridal suite, event day valet parking, and a maitre d, bridal attendant and captain.

The aggregator Wedding Spot lists $195 per person for an on-peak Saturday, a 140-guest minimum, and a starting total of $25,290 for 140 guests. That is an aggregator figure. The venue’s private events page now publishes its own: starting at $119 per person. We had removed that figure earlier because we could not source it, and we have restored it now that the venue prints it.

Set whatever they quote you against the county medians on our pricing page, and put your real headcount through the cost calculator before the tour, not after it.

Four hundred, three hundred, or a thousand

The weddings page says the mansion accommodates up to 400 guests for a seated dinner or 300 for a cocktail-style reception, which is backwards from the way most rooms behave, and separately describes a ballroom holding up to 300. The homepage adds outdoor lawn events for over 1,000 and indoor gatherings up to 300. Those three statements do not reconcile without a tent, and the site never mentions one.

Get the seated number for your specific room, in writing, before any deposit moves. One thing they are clear about: maximum one event per day.