What's the best companion to your Subway footlong sandwich? How about a free footlong cookie?

Starting in December, Subway is introducing a footlong chocolate chip cookie to a select group of restaurants across the country. The footlong cookie will become a permanent part of Subway's menu starting in 2024.

And just in time for National Cookie Day on Dec. 4, Subway will be offering a free footlong cookie with the purchase of a footlong sub sandwich at special stores in Chicago, Dallas, Miami and New York.

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National Cookie Day: Where to get a free footlong cookie at Subway

On Dec. 4, select Subway restaurants are being transformed into "Cookieway," and will be offering a free footlong cookie with the purchase of any footlong sub sandwich. The participating restaurants will be offering the free cookie from 1-6 p.m. local time, while supplies last. Here's where to find the footlong cookies:

• Chicago: 604 S Wabash Ave., Suite D, Chicago, IL 60605 
• Dallas: 1222 Commerce Street, Suite 150, Dallas, TX 75202 
• Miami: 2795 Collins Ave., Miami Beach, FL 33140 
• New York City: 545 8 Ave., New York, NY 10018 

“The overwhelming response we received from fans around the country last year let us know that we needed to make the footlong cookie a permanent addition to our menu,” said Paul Fabre, Senior Vice President, Culinary and Innovation at Subway, said in a press release.

Similar to Subway's popular regular-sized cookie, Fabre said the footlong version will be “thick, gooey, packed with chocolate chips and served warm – right out of the oven."

"It’s the perfect pairing with your favorite footlong sub and may even become your favorite footlong after the first bite.”