The current program is said to be much simpler. Customers earn 12 stars -- the equivalent of 12 visits -- to get a drink or another treat for free.
The changes to the program mean customers will have to spend $62.50 before they can redeem a free item.
According to Starbucks, the change is a response to customer feedback.
But for customers who spend $4 per transaction, that means they'll have to visit a Starbucks store more than 15 times to reap the benefits of the new rewards program. Anyone who regularly gets just a $2 cup of coffee every morning before work will have to do so for a full month -- 32 trips -- before getting something for free.
Starbucks has responded to unhappy customers by asserting that there are other ways to earn stars, including purchasing Starbucks products in grocery stores and making in-store purchases on monthly "Double-Star Days." The company is also encouraging customers to explore the menu beyond drink choices.
"If you occasionally buy a food item -- like breakfast, lunch or a pastry -- with your usual beverage, you'll likely earn free rewards just as fast or faster than you do today," Starbucks said.
Starbucks' rewards program, which began in 2009, has had a tremendous impact on the chain's mobile sales, which now account for about 6 million orders a month, according to Nation's Restaurant News.