Depending on the burger King they sometimes will except expired coupons. They had a sign out for a while saying this.
Burger king has now said that they will take any and all burger king coupons, even those that are expired.
The only time expired coupons cannot be accepted is if it is good for a food they don't have any more, like hot dogs, double stackers ect
Coupons to Burger King will often have a printed expiration date on the back.
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