While use by consumers of the Isis Mobile Wallet is believed to have been low, in general, in the pilot cities of Austin, Texas, and Salt Lake City, Utah, at least two issuers appear to be sufficiently convinced of the concept to move forward with Isis on its national rollout.

JPMorgan Chase Bank today announced it would allow its credit cardholders to load their cards into the Isis Mobile Wallet around the country to make mobile payments. Cardholders of four of the bank’s credit cards will be able to load the cards into the wallet.

That follows an announcement late last week by American Express that it would make its Serve account available to the Isis wallet as part of the nationwide launch. Users would be able to tap to pay with the ExpressPay application tied to the Serve account, which users could fund with credit or debit cards, through their bank accounts or by cash. They will also be able to pay bills online and do funds transfers with Serve from the Isis wallet.

Chase and American Express will not be the only issuers onboard for the national launch, which is tentatively set to begin around October, according to sources. Isis has said other financial institutions will offer their cards for the wallet.

The participation by the U.S. issuers come with a price tag, with SIM rental fees charged by Isis and fees issuers must pay to their own trusted service managers, if they have one, costing much more than what it would cost to issue conventional payment cards.

But Chase and AmEx, along with other banks that join the Isis rollout, apparently see Isis as a credible initiative that is worthy of placing a bet on in the uncertain world of mobile payments.

And while the issuers don’t control the Isis wallet user interface, the wallet supports conventional payments companies, which face threats from such new payments players at the physical point of sale as PayPal, MCX and Google, though the latter's Google Wallet has not taken off.

Isis has not released transaction figures or specific numbers of users for its two-city pilot, which began last October, saying only that “active” Isis Mobile Wallet users “tap more than 10 times per month,” and that two-thirds of active users “opted in to receive offers and messages from their favorite brands, following an average of seven brands.”

AmEx offered an ExpressPay contactless payment application in the wallet for the pilot. It said last week that the trial taught it that “customers love the convenience of tap and pay with the ability to manage their payments and loyalty programs from one app.” The company said its Serve accounts would be available in every Isis Mobile Wallet for the rollout.

Chase called the two-city pilot “successful” and that it showed “positive results.” A spokesman of the bank, in response to a question from NFC Times, declined to say how it defined success, however, or to elaborate at all on its statement of support for the Isis rollout.

Besides offering a credit card for the wallet in the pilot, Chase also issued the Isis Cash Card, a prepaid application that supports Visa payWave at the point of sale.

Capital One, the third issuer participating in the Isis pilot, has not yet announced whether it will join the national rollout.