NEW JERSEY - Those looking to fill up for cheap after July 4 may have to find gas elsewhere as Costco's membership-only gas sales begin in the Garden State on Tuesday.

That means in order to purchase fuel at one of Costco's 15 fuel stations in New Jersey, you'll have to show a membership card.

Costco annual memberships retail for $60. As of July 5, two Costco gas stations, Edison and North Brunswick, topped GasBuddy.com's list of stations with the cheapest prices in the state, touting about $4.40 per gallon. That's compared to a statewide average of $4.81 per gallon as of Tuesday.

Despite a months-long gas price hike attributed to high demand for summer travel and worldwide oil trade turbulence, gas prices this week have modestly dialed back. According to AAA, gas prices are down 15 cents on average from a month ago, but still over $1.65 higher than average prices this time last year.

This isn't the first time Costco has vied to reserve its lower gas prices for members only. Several warehouse chains attempted a similar membership requirement for gas purchase in 2004, but the effort was halted by the state when it found the policy in violation of NJ fuel sale laws.

In June, the DCA, part of the state Attorney General's Office, told multiple news outlets that members-only gasoline sales are not in violation of any consumer protection laws in the state. It wasn't immediately clear how the Attorney General's Office came to a different conclusion this time around. Last month, a state Treasury Department spokeswoman said last month that Costco is in the clear as long as motor fuels taxes are paid, NJ.com reported.

The new members-only gas policy was never formally announced by Costco in a news release or on its website but was instead advertised through notices posted at its warehouse fueling stations around the state. Read more: NJ Costco Stores To Require Membership For Gas Purchases

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