The Common Brain Hack Fast Food Restaurants Use to Trick You Into Buying More

Fast-food prices keep climbing. And some restaurants use a sneaky trick to make you spend more than planned, a psychotherapist told Fox News Digital.

This trick is called "charm pricing." It’s why menu items rarely have round-dollar prices, said Jonathan Alpert, a New York-based psychotherapist and author.

"Our brains process numbers quickly and often emotionally, especially during purchasing decisions," Alpert said.

When something is priced at $9.99, "our minds latch onto the '9' as the anchor, associating it with a smaller cost, even if logically we know it's close to $10," he explained.

The food and culture website The Takeout calls this the "left-digit effect."

"This can trick you into feeling like an item is less expensive," the site noted.

"If you're buying three items priced at $5.99, your brain might immediately assume the total is $15, when in actuality it's closer to $18."

That slight difference can make people feel like they’re getting a deal.

But charm pricing isn’t the only tactic. Restaurants use other tricks to get customers to spend more, Alpert said.

Things like "an appealing menu design or descriptive language" can make a meal seem more indulgent, he added.

A man stares up at the menu, trying to decide. He may think he’s getting a bargain when he’s really not.

Alpert said there are ways to avoid overspending.

"A helpful tip is to always round up," he suggested. "When you see $9.99, think of it as $10."

This small change "can reduce the emotional impact of charm pricing and help you make more rational decisions."

Another smart strategy? Slow down before you buy.

"Pause and ask yourself if the item is really worth the cost or if you're being swayed by how it's presented," Alpert advised.

"Developing mindful spending habits can help you resist psychological tricks and make choices that align with your goals," he added.