CEO Jim Skinner made the word official at its annual shareholders meeting at McDonald's Corp. headquarters in Oak Brook, Ill.
McDonald's has lagged other restaurant operators in switching over to a zero-trans-fat cooking oil out of worries it would compromise the taste of its trademark fries. It has been under increasing pressure from consumer advocates and some public officials to make the change, but did so quietly.
"For a few months now, customers in our U.S. restaurants have been enjoying our fried food items, including french fries, hash browns, chicken and filet of fish, as well as our biscuits, with zero grams of trans fat per labeled serving," Skinner said.
He said McDonald's is on schedule to convert to the new oil by year's end for its remaining baked items, pies and cookies.
"While we don't plan to advertise these changes, we wanted you to be the first to know that we have followed through on our commitment while keeping the same great taste that our customers expect from McDonald's," Skinner said.
The $23 billion company was especially cautious in making the switch after reneging within months on a September 2002 pledge to introduce a new oil, citing the taste concerns.
McDonald's has nearly 14,000 restaurants in the United States.
Shares in the company fell 16 cents to $58.62 in midday trading.