New data from fintech analysts at Juniper Research forecasts that the global value of contactless transactions made via payment cards, mobile devices and wearables, will reach $1.3 trillion by 2019, more than doubling from an estimated $590 billion in 2017.

Further, Juniper forecasts that contactless transactions via debit and credit cards will exceed $2 trillion globally by 2021.

According to a new report from Juniper, Contactless Payments: NFC Handsets, Wearables & Payment Cards 2017–2021, cards will continue to dominate cardless transactions, accounting for 80 percent of the total in 2019.

The research found that many markets with a relatively well-established contactless infrastructure have been seeded by the card providers — with varying degrees of success.

For example, Juniper found that in 2016, cards accounted for more than 90 percent of contactless transactions by value in many European markets, but in the U.S., the position was reversed, with mobile wallets accounting for 90 percent of contactless transactions.

"Purely from a payments and convenience perspective, it will be difficult for mobile wallet providers to gain existing market share from contactless cards," said research author Nitin Bhas. "It is therefore incumbent upon them to deliver innovative services through which the mobile wallet will become the default payment mechanism."