Americans are expected to spend $2.87 billion on Halloween costumes this year, according to a National Retail Federation survey released Thursday.

The spending breakdown was projected to be $1.4 billion on adult costumes, $1.1 billion on children’s costumes and $370 million on pet costumes.

The average person will spend $79.82 on Halloween candy, costumes and decorations, bringing total spending to $8 billion — the most in the survey’s 10-year history.

This year, trick-or-treaters, partygoers and pampered pets will be dressing up in traditional spooky style, with witch, princess, vampire, pirate and pumpkin costumes among the favorites in the NRF survey, which was conducted by BIGinsight.

Nearly 6 million adults plan to dress as a witch this year, and 3.2 million will dress as vampires. For kids, princess costumes take the No. 1 spot (9.7 percent), followed by Batman (5.4 percent) and Spider-Man (4.6 percent).

When it comes to choosing a costume for their four-legged friends, 12.7 percent of people are sticking with the traditional pumpkin.

Many consumers are looking to recent and forthcoming events for their 2012 costume ideas. More than 1 million adults and kids will dress as some type of athlete, a nod perhaps to the London Olympics. And with the election looming in early November, about 770,000 partygoers will don some type of political costume, mostly as Barack Obama and Mitt Romney look-alikes.

A record 170 million people plan to celebrate Halloween this year, the survey said.