Every rule guests attending Heidi Klum's Halloween party must follow as some risk being turned away

Securing an invite to one of the most exclusive Halloween parties in the world doesn't necessarily guarantee you'll make it through the doors, Heidi Klum has previously warned.

The supermodel once again took Halloween costumes to a whole new level last night (October 31), as she hosted her iconic bash at Cathédrale Restaurant in New York City.

Some of the names on this year's star-studded guest list included Neil Patrick Harris, Paris Jackson, Kyle MacLachlan and Eric McCormack.

But merely securing an invite to the exclusive Halloween celebration is not enough to get past security, according to the star - who attended her party dressed as her own severed left hand.

Klum has previously warned that any guest without a costume will simply be turned away at the door.

After hosting her first event in the year 2000, the 53-year-old admitted at the time that 'the majority of guests were not super dressed up'.

Speaking with the Hollywood Reporter, she said: "So, after that, I implemented a 'no costume-no entry' rule. We quickly taught people that if you don’t come in a costume, you’re not getting in. The costumes get bigger and better every year. And that’s because guests know they won’t get in unless they bring it."

Klum's costume was meticulously detailed. (Noam Galai/Getty Images for Heidi Klum)

But the costume requirement isn't the only rule guests should be aware of before arriving.

The party is invitation-only - with the exception of one fan who was able to get access to the event this year, after winning a ticket via charity auction, in which the winning bid reached $4,482.

A special wristband is also needed for certain VIP areas within the venue, according to a journalist who attended the infamous party in 2019.

A reporter from Entrepreneur claimed that two private areas were restricted to guests with special wristbands, including the back patio and the area beside the stage, which was reserved for the icon's close friends and colleagues.

Guests are expected to 'bring it' with their costume creations. (John Nacion/Variety via Getty Images)

Guests may also have to wait a while to catch a glimpse of the host herself, as he noted that Klum typically doesn't make her entrance until shortly before midnight.

Speaking about her crazy transformations, Klum said: "By me doing crazy, elaborate outfits as the host, my hope had always been that all my guests would follow. And it’s worked because, over the years, people have become increasingly more outrageous with their costumes."

And as for when she starts considering next year's costume, the star doesn't waste any time at all.

"I start thinking about it on Nov. 1! I usually have two or three ideas that I’m playing with and then I decide on one thing," the mom-of-four admitted.