While Sunday is the actual first day of the season, the company is extending its "sweetest event of the season" to the first week of spring.
From March 20 to March 27, customers can get their Free First Day of Spring Ice - but you have to download the Rita's app to get it.
"This year, our celebration lasts all week, giving you cool perks like shorter lines, better service and more convenience. Just download our app before or on the First Day of Spring," Rita's says.
That's important. Rita's says you must have the app by March 20 to be issued the Free Ice reward.
"You'll have a whole week to use your reward and get your Free Ice! And parents will be able to redeem Free Ice for their children using their reward," Rita's says.
The water ice is served in a 7-ounce limited edition First Day of Spring cup.