The Departments of Defense and Veterans Affairs are gearing up for what will be the largest expansion of patrons to the military commissary system and exchanges in 65 years, making sure that shoppers will be able to get on base and find the shelves fully stocked.

Starting Jan. 1, Purple Heart recipients, former prisoners of war and all service-connected disabled veterans, regardless of rating, as well as caregivers enrolled in the VA's Comprehensive Assistance for Family Caregivers program, will be able to shop at Defense Commissary Agency stores and military exchanges.

They also will have access to revenue-generating Morale, Recreation and Welfare amenities, such as golf courses, recreation areas, theaters, bowling alleys, campgrounds and lodging facilities that are operated by MWR.

Facilities such as fitness centers that receive funding from the Defense Department budget are not included.

At commissaries, however, there will be an added cost for new patrons who use a credit or debit card to pay for their groceries, in addition to the 5% surcharge commissary patrons already pay.

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DoD officials told Military.com on Wednesday that an estimated 3.5 million new patrons will be eligible to shop. However, after analyzing store locations and their proximity to where veterans live, they expect that slightly more than a quarter of those patrons, or 800,000 people, will take advantage of the benefit.

According to Barry Patrick, associate director of MWR and Resale Policy in the Office of the Under Secretary for Personnel and Readiness, the DoD expects veterans in high-cost areas like Guam, Alaska, Hawaii and parts of California to take advantage of the benefit. Stores in states or cities with large populations of service-connected disabled veterans, including Florida, California, parts of Texas and Washington, D.C., may also see an increase in customers.

"Through this data analytics tool that we've developed, we've been able to provide the services and the resale organizations information ... to ensure that [they] can adjust," Patrick said. "We are working with distributors to ensure that the supply chain is adjusted accordingly, based on high-impact projections, and that the supply chain is also prepared for rapid, agile reaction to any unexpected situation."

In addition to ironing out the supply chain concerns, Pentagon officials also have been working to guarantee that the new patrons can get to the stores, which often are located on secure military installations, and will be able to make purchases.

The details have required a joint effort for much of the past year between the DoD and the Departments of Veterans Affairs, Homeland Security and Treasury. Homeland Security is involved because Coast Guard Exchanges are part of the deal, and Treasury plays a role, because it is responsible for ensuring that new patrons pay a fee for credit and debit card purchases at the commissaries.

Since most new patrons lack the credentials needed to get on military bases, installations will accept the Veteran Health Identification card, or VHID, from disabled and other eligible veterans. For caregivers, the VA plans to issue a memo to eligible shoppers in the coming months, which will be used in conjunction with any picture identification that meets REAL ID Act security requirements, such as a compliant state driver's license or passport.

Justin Hall, director of the MWR and Resale Policy in the Office of the Under Secretary for Personnel and Readiness, said that, after Jan. 1, newly eligible patrons should go to the visitors' center at the base where they plan to do most of their shopping to register their credentials. Thereafter, they will be able to access the base in the same way as CAC and DoD ID card patrons.

According to Hall and Patrick, store computers and registers are being tweaked to scan VHID cards, and employees are being trained on identifying the new patrons.

The most significant difference mandated in the law that created the benefit, the fiscal 2019 National Defense Authorization Act, is that the new customers must pay a fee if they use a credit or debit card at the commissaries. By law, the stores, which receive funding from the Defense Department budget, are not allowed to cover the extra cost of the new users' card convenience fees.

The initial fee for commercial credit cards will be 1.9%; for debit cards, it will be 0.5%. Patrons can avoid the card fees by paying by cash or check, or by using the Military Star card, a credit card offered by the military resale system, which they will be eligible to apply for beginning Jan. 1.

The card fees will apply only to the new patrons.

The Defense Department is preparing a fact sheet that will contain information on how veterans can get a VHID card if they don't already have one and how caregivers can obtain the memo they need to access the benefit.

MWR and Resale Policy officials said they also will launch an information campaign to alert service-connected disabled veterans of this new benefit.

"Everybody I've talked to is excited," Hall said. "We're really hoping to get the word out so veterans will learn about the opportunities."

-- Patricia Kime can be reached at Patricia.Kime@Military.com. Follow her on Twitter at @patriciakime.

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