A cup of Starbucks coffee in Japan just got smaller.

A short drip coffee purchased at a Starbucks store in Tokyo’s Marunouchi Building on Dec. 18 was filled 20 millimeters from the top, lower than the new guideline of 15 millimeters. Photographer: Nelson Ching/Bloomberg

Starbucks Coffee Japan Ltd. (2712), an affiliate of the world’s largest coffee-shop operator, said it reduced the amount of drip coffee it pours into each cup by 9 millimeters (0.35 inch), reflecting customers’ requests to avoid spilling drinks and add room for milk.

The move risks angering consumers in a country where a small cup of drip coffee costs 300 yen ($3.60), more than double the $1.70 after tax in Seattle, where Starbucks Corp. (SBUX) is based. Starbucks Japan has raised prices three times since 2006, bucking the deflation that has squeezed growth in the world’s third-largest economy.

“I like the taste of Starbucks, but it’s a bit expensive,” said Osamu Kawaguchi, 50, who runs an air conditioning company in Saitama prefecture, near Tokyo. “At that price I’d prefer more coffee,” he said after buying two cups of drip at an outlet in the Japanese capital on Dec. 18.

Starbucks Japan, which increased prices for some smaller drinks in 2011 to reflect higher costs of ingredients including coffee beans, posted record profit of 3.2 billion yen for the six months ended Sept. 30. It operated 965 stores in the country as of Sept. 30.

Spilled Drinks

A short drip coffee purchased at a Starbucks store in Tokyo’s Marunouchi Building on Dec. 18 was filled 20 millimeters from the top, lower than the new guideline of 15 millimeters. Previously, staff were told to pour 6 millimeters from the rim.

“Customers complained that they spilled coffee and got burned because cups were filled too high,” Norio Adachi, a Tokyo-based spokesman, said by phone. The move wasn’t prompted by cost cutting, he said.

World coffee bean prices have eased this year. Arabica has plunged 53 percent from a 14-year high of $3.089 a pound in May 2011, according to ICE Futures U.S. in New York, after growers boosted production and processors added cheaper robusta beans to blends.

Shares of Starbucks Coffee Japan fell 0.2 percent to 58,000 yen as of the 11:30 a.m. trading break. They have risen 18 percent this year.

“I have been feeling uneasy with the very full coffee,” Shuhei Sano, a 32 year-old customer said after buying a cup at a Starbucks in Tokyo’s Akasaka district. “It’s difficult to drink if it’s full. I had to take an extra care on the first sip.”

Adachi said Tokyo-based Starbucks Japan will listen to customers’ feedback on the policy change and honor any requests to fill cups higher.

Some customers questioned the move to serve less coffee at Starbucks’ current prices.

“The company should have informed customers about the guideline changes,” said Yumiko Sakaue, a 36 year-old telecommunication company worker. “They should go back to the previous amount unless they lower the price.”