The promotional glasses were sold for $1.99 with a food purchase and $2.49 without.
The company decided to provide a $3 refund to "account for taxes customers may have paid," a spokeswoman said.
To get the refund, customers must return the glasses inside a McDonald's store and fill out a refund slip. A receipt is not required.
Cadmium was discovered in the painted design on the glasses, which were sold nationwide by the Oak Brook-based restaurant chain, forcing the company to recall 12 million of the glasses.
The U.S. Consumer Product Safety Commission last week warned consumers to immediately stop using the glasses, noting long-term exposure to cadmium can cause adverse health effects.
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