Theme parks in the US are capitalising on the festivities of Halloween, which is the single-largest theme park promotion every year, according to global consultants International Theme Park Services (ITPS).

With Halloween firmly set as a staple of the attractions sector, prompting millions of people to visit theme parks across the US and the rest of the world, the industry is aiming to grab a larger slice of the annual event worth more than US$7bn (€6.2bn, £4.6bn) a year to the US alone. It is the second-largest commercial programme after Christmas.

Dennis Speigel, president of ITPS, said that theme parks are seizing on the concept of creating haunted houses and scary in-park promotions after seeing the success many cities were having drawing visitors to horror attractions across the US. All of the major operators, including Disney, Universal, Six Flags and Cedar Fair now have a an annual programme in place at their parks in some shape or form.

Most programmes run the month through October and sometimes into early November, with Knott’s Berry Farm one of the originators of the idea, starting its Halloween festivities in 1973, growing year-on-year with more than 400,000 visiting in 2014. Universal is the leader in Halloween horror attractions, drawing more than 600,000 visitors in 2014 for its annual Halloween Horror Nights, which this year will enter its 25th edition.

“The success of the US theme parks in carrying out these Halloween events has been exported around the world,” said a report by ITPS. “The event is now popular in countries that actually do not have a ‘true’ Halloween observance.”

With Halloween experiences at theme parks and visitor attractions growing in size every year, ITPS predicts these events will become more interactive and more immersive, incorporating more horror IPs and drawing more visitors.

“Overall, 2015 has been a good season for our industry,” said Speigel. “If weather remains good throughout October, the industry will see a significant jump over 2014’s attendance, and these Halloween events will have made a huge contribution to that increase.”

Further investment into Halloween has seen theme parks and visitor attractions team up with big names to drive further traffic and increase footfall. Among those involved this year, Universal is collaborating with director Guillermo del Toro, Busch Gardens has brought in Blair Witch producer Robin Cowie and Slipknot are launching a horror attraction as part of the returning Scream Park Sacramento.