National Taco Day falls on Friday, Oct. 4 and restaurants around the US are celebrating with either free tacos or specials.

According to NationalTacoDay.com, Americans ate more than 4.5 billion tacos last year, which is approximately 490,000 miles of tacos at a total of 775 lbs.

Chains such as Taco Bell and Jack in the Box are offering specials that taco fans can take advantage of:

-Taco Bell: Customers can order a "National Taco Day gift set" for $5. The gift set includes four tacos – two Crunchy Tacos and two Nacho Cheese Doritos Locos Tacos.

-Burger King: Participating locations have $1 crispy tacos.

-Jack in the Box: Customers can get a free taco with any purchase, as long as they sign up for the Jack in the Box e-club.

-On the Border: Participating locations are offering Endless Tacos for either $8.99 or $9.99.

Friday is also National Vodka Day, but there are far fewer discounts for spirits.

Mexican restaurants and taco joints are expected to be busier than usual for a Friday, according to data from Womply, a small-business software provider.

"On National Taco Day, foot traffic to Mexican restaurants and taco shops is only slightly above average, so you shouldn’t have any trouble if you decide to get yourself a taco at your favorite local eatery,” Brad Plothow, Womply's vice president of brand and communication, told reporters.