Apple Pay is now accepted by 36 percent of merchants in the United States, according to research conducted by retail consulting firm Boston Retail Partners and shared by NFC World. That's up from 16 percent last year.

Boston Retail Partners derived its information from a survey of more than 500 top North American retailers.

22 percent of retailers who don't currently support Apple Pay said they plan to accept the payments service within the next 12 months, while 11 percent plan to do so in the next one to three years. 31 percent plan to take a "wait and see" approach before implementing Apple Pay support.

PayPal was the next most widely accepted payments service at 34 percent, while MasterCard's PayPass came in third with 25 percent. 24 percent of merchants claimed support for Android Pay, while 18 percent said they accept Samsung Pay. Given that many of these technologies are all NFC-based and accepted anywhere NFC payments are available, it seems merchants may be referring to "official" support or may be unaware of the way contactless payments work.

"PayPal has been bumped out of its top spot in this year's survey, with Apple Pay now being accepted at 36% of the retailers participating in the survey. This is up significantly from 16% last year, and signals a growing acceptance by retailers and customers." "This year, fewer retailers are adopting a wait and see approach for Apple Pay and PayPal -- likely because of the growing support from the payment software ecosystem and the acceptance for these mobile payments by the public."

During Apple's recent first quarter earnings call, Apple CEO Tim Cook said Apple Pay usage had tripled over the course of 2016. Transaction volume was up more than 500 percent year-over-year, and according to Cook, more than two million small businesses now accept Apple Pay.