Here's where to get free and specialty burgers on National Cheeseburger Day

Attention, burger fans. Sept. 18 is National Cheeseburger Day.

(credit: Brio Tuscan Grille)

Whether you like your burger piled high with lettuce and tomato or slathered with chili, you're in luck. There are plenty of special deals available on Sunday.

Some 57 percent of consumers in the U.S. ate burgers more than once a week in 2015, according to Technomic's Burger Consumer Trend Report. That number is down slightly from 2013, when 68 percent of Americans reported chowing down on burgers more than once in a week.

Here's a round-up of where to snag free, discounted and specialty burgers:

Receive a free burger (up to $10 value) with the purchase of an adult entree on Sunday at Ruby Tuesday. In order to redeem the coupon, customers must be signed up for the restaurant's SoConnected email club.
Black Angus Steakhouse is offering a coupon for customers to get any lunch entree for $8.99, including the Steakhouse Bacon Cheeseburger and Guacamole Burger, until Sept. 19.
BurgerFi is selling $5 cheeseburgers on Sunday, which come with two beef patties, two slices of cheese, lettuce, tomato and BurgerFi sauce.
Delta will serve Shake Shake burgers aboard select flights from JFK to LAX on Sunday. In addition, customers on the flights will receive a voucher for a free ShackBurger at the LA West Hollywood Shake Shack.
Hurricane Grill & Wings is offering $5.99 beef, turkey or veggie burgers with cheese, lettuce, tomato, onion and pickles on Sunday.

Not everyone is heading out to eat for National Cheeseburger Day, however. Social media users have been posting tasty photos of their own burger concoctions ahead of the food holiday.