BOSTON (CBS) — Dunkin’ is serving up a big surprise this week for a lucky few customers. Twenty-one people people across New England will win a year’s worth of Dunkin’ coffee.

Customers will be surprised at different locations all week long. On Wednesday, winners will be picked in North Reading, Worcester and Meredith, New Hampshire. On Thursday, people in Boston will have their shot at the prize.

Winners may be selected when ordering in-store or at the drive-thru. The prize of free coffee for a year is awarded in gift cards totaling $598.

It’s all to promote Dunkin’s new Extra Charged coffee that has 20% more caffeine.

Click here for a list of all the participating New England locations