The AT&T logo is pictures on a building in Los Angeles, California, U.S. August 10, 2017. REUTERS/Mike Blake

BARCELONA (Reuters) - AT&T is upbeat on long-term revenue prospects for 5G services but expects it to take years before 5G-enabled devices predominate, CFO John Stephens said on Wednesday.

AT&T, the second-largest U.S. wireless carrier, has developed some use cases for the next-generation mobile technology, such as connected factories, but does not expect 5G-enabled handsets to hit the market until late 2019 or 2020.

“It’s an exciting spot. We’re ready. But I’m not here to make any predictions on revenue opportunities in ‘19,” Stephens told the Morgan Stanley TMT Conference in Barcelona.

Stephens said only around 5 percent of users were getting a new smartphone each quarter, indicating it will take time for the sector to grow.

“On revenue opportunities, will we say in five years, how did we ever live without this? I would say yes,” Stephens said.