Taco Bell wants to sell you a 30-day taco subscription. Here's how it works.

Taco Bell is testing a tasty monthly subscription service.

In about 20 participating restaurants across Tucson, Arizona, customers can pay between $5 to $10 per month for a Taco Lover's Pass, which gives subscribers one taco a day for 30 days. The app-based program is currently active until November 24.

A variety of tacos are included in the subscription, including a soft taco, spicy potato soft taco, crunchy tacos and its Doritos tacos. Once a customer subscribes to it, a special section within the app is unlocked and customers can add a taco to their cart during the checkout process.

Subscription services are more common for streaming, but restaurants have also experimented with them. Panera has an $8.99 monthly program that lets customers get a free hot or iced cup of coffee every day. Burger King had a similar coffee subscription but has since scrapped it.

Taco Bell likely hopes the trial turns casual customers into regular customers and increase enrollment in its year-old loyalty program. The idea is to lure people in with a free taco and hope they add more to their order and increase the amount they spend at the restaurant. It also gives restaurant owners information about ordering habits that help target diners with customized deals.

Yum Brands, which owns the taco chain, said in its recent earnings call that it's aiming to grow digital sales this year with more exclusives, such as this one. App users enrolled in its loyalty program spend 35% more compared prior to joining, it said.

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