On March 12, customers can get a free small Thin Mints Frosty with any purchase in the mobile app at participating Wendy’s restaurants nationwide, according to the Ohio-based burger chain. The one-day offer can also be redeemed online, Wendy’s said.

In honor of National Girl Scout Day on March 12 and St. Patrick's Day on March 17, Wendy's is offering free Thin Mints Frostys and Fries this week, respectively. Customers can grab the deals through the Wendy's app or website.

This new Frosty drop was perfectly timed for National Girl Scout Cookie season, and now you can snag one for free. In honor of National Girl Scout Day on March 12, Wendy’s is giving away free small Thin Mints Frosty treats with any purchase—exclusively through the Wendy’s app.

And what goes better with a Frosty? How about fries? Now through March 17, St. Patrick’s Day, Wendy’s is giving away free fries with a $5 purchase and drink. Again, you’ll need the app to claim the offer. As always, the deals are subject to a location’s participation, USA Today reported.

Wendy's announced at its Investor Day last week it will be introducing two new Frosty varieties to its menu this spring.

The Wendy’s Frosty is a perennial favourite on the menu with the beverage traditionally available in classic flavours such as: Chocolate and Vanilla with the likes of limited edition seasonal flavors such as Salted Caramel, Peppermint and Strawberry also hugely popular.

Wendy’s, the popular fast food chain, celebrates National Girl Scout Day with a surprise for all its customers