Some Starbucks locations quietly raised prices on brewed coffee and cookies on Pumpkin Spice Latte launch day

Starbucks just quietly raised prices at a sizable chunk of locations. 

On Tuesday, certain Starbucks locations raised prices on 10% of menu items, including some sizes of brewed coffee, select espresso drinks, bacon Gouda breakfast sandwiches, and cookies. Price increases ranged from 10 to 30 cents and varied based on the market. 

Starbucks' price hike - which comes on the same day as the official Pumpkin Spice Latte launch - isn't national, though the company declined to say how many of the chain's roughly 8,000 US locations raised prices on Tuesday. 

"We expect 10% of the US customer's average customer ticket to increase by about 0.5%  as a result of these beverage adjustments," Starbucks spokesperson Sanja Gould told Business Insider. 

Some customers in affected areas are already annoyed. 

Gould said that the price hikes are part of Starbucks' ongoing approach to determining prices. 

"Pricing is continually evaluated on a product-by-product and market-by-market basis in our stores in order to balance business needs while continuing to provide value to our loyal customers," Gould said. 

The last notable Starbucks price hike was in November 2016, when the chain raised prices on 10% of its offerings - including cold drinks, such as cold brew, and certain bakery items - at the majority of locations. 

Starbucks has struggled to grow traffic recently, with the number of customer visits to US stores staying roughly the same or dropping every quarter for the past year. However, the chain has managed to increase US sales by convincing customers to spend more when they do visit Starbucks.