When is The Best Day to Buy Gas in Maryland?

When should you fill up your gas tank? There's a day for that.

In Maryland, the cheapest day to buy gas is Thursday.

And if someone told you how to get a tank or two of free gasoline every year, you'd listen, right?

Well, here's the "trick," based on hard data.

Federal researchers have found gas prices follow a cyclical pattern in the Mid-Atlantic region, with Thursday being the best to fill the tank in Maryland and Delaware for the last three years.

Maryland drivers should expect to pay $2.31 a gallon for regular, unleaded gasoline this weekend on average, which is nearly 40 cents a gallon less than a year ago, according to AAA Mid-Atlantic.

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Petroleum analyst Patrick DeHaan told NBC News that prices were lowest on Friday, Saturday or Sunday in about two-thirds of states. GasBuddy’s analysis found that Maryland’s cheapest day to buy gas is Thursday.

AAA Mid-Atlantic projects 814,000 Marylanders will travel this Memorial Day holiday weekend, a 1.6 percent increase compared to the number of travelers in 2015.

Recent research by YiLi Chien and Paul Morris of the Federal Reserve Bank, in a report called When Should You Buy Gas?, analyzed gas prices from October 2015 to March 2016 using Gas Buddy data.

They say gas prices follow a "cyclical saw-tooth pattern," and knowing this pattern could save you enough money to pay for one or two tanks of gas every year.

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