Convenience store chain Circle K , which has more than 4,000 stores in 22 states, is giving members of its Inner Circle loyalty program 40 cents off per gallon on Thursday, Aug. 21.

To get the Inner Circle Fuel Day deal, customers must enter the phone number associated with their Inner Circle account at the gas pump or inside the store at checkout before their transaction. The discount is good for one use at participating locations only.

Here's what we know.

When is the Circle K gas discount?

The Inner Circle Fuel Day deal is available from 6 a.m. to 11:59 p.m. on Thursday, Aug. 21.

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Does Circle K offer gas discounts on holidays?

In the past year, Circle K has had 40-cent price reduction Fuel Day promotions for Memorial Day , Thanksgiving

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