There’s nothing more romantic than brand sponsorship.

An Instagram influencer’s elaborate “surprise” engagement was recently shopped around to companies, which were asked to back the couple’s special moment with sponsorships.

“We’re pleased to offer your brand the opportunity to align with this momentous occasion,” reads part of the 13-page pitch deck for the engagement of New Yorkers Marissa Fuchs, who runs the popular account @FashionAmbitionist, and her boyfriend, Morgan Stanley financier Gabe Grossman.

The more than 180,000 users following Fuchs have been tuning in to watch her elaborate marriage proposal play out. The stunt began on Tuesday when she posted a video of her boyfriend talking up their engagement with the caption: “WHAT IS HAPPENING?!!!!!!!!!!!!!!!!!!!”

The next post was of pictures of Fuchs taken by the company Flytographer with the caption: “Can’t sleep in anticipation of tomorrow @gabriel.grossman this is tooooo much to handle.”

But when the pitch, obtained by The Post, leaked online, many people began wondering whether Fuchs had been feigning her surprise and was in on the plan from the start.

Fuchs’ Thursday post captioned, “STILL NO RING!!! Was completely shocked…,” was met with snide remarks from users calling the engagement ‘staged as f–k.'”

Titled, “#LoveAmbitionist,” the document lays out the “one-of-a-kind proposal experience,” which so far has included gifts of dresses and jewelry, a helicopter ride to Montauk and a lavish dinner in Miami.

The next leg of the trip is in Paris, where on Friday afternoon, Fuchs, 30, is scheduled to be proposed to following a flash mob on the steps of the Louvre.

The pitch deck lays out a calendar that includes scheduled posts. So far, the plan has been nearly in sync with what’s on Fuchs’ Instagram, arousing suspicion that she must have seen it.

But in emails to The Post, Fuchs said she’s only been using her phone to check incoming messages from friends and family.

Fuchs, the director of brand partnerships at Goop, maintained that she didn’t find out about the existence of the deck until Wednesday.

“I still haven’t seen it and still don’t know what’s in store for the rest of the engagement.”

It’s apparently the work of her 30-year-old boyfriend, a former Michael Kors employee and pal named Elicia Blaine Evans and other friends.

As to whether any brands actually bit and sponsored part of the proposal, Fuchs said: “I know people are saying that everything was sponsored— but that couldn’t be less from the truth.”

“Gabe has paid for every inch of this proposal.”

Fuchs admitted to receiving a handful of summer dresses from friends at a company and something from the indoor-cycling studio Flywheel, for which she’s a brand ambassador.

Asked what she thinks about brands sponsoring intimate moments like engagements, Fuchs said, it’s “fine” if the people involved had a previous relationship with the companies or if its a brand they love.

“At the end, it’s all about showing love for the people you care about,” she said.

Whether a sly marketing ploy or total surprise, the influencer’s engagement journey has brought her an additional approximately 30,000 followers. Perhaps an early engagement present?