Wireless carriers may be moving full steam ahead on 5G networks, but 5G handsets aren’t expected to make their way to the United States until 2021, Strategy Analytics said in a new report.

According to the report, the first 5G handsets are expected to launch in South Korea and Japan in 2020, with launches in countries like the United States, United Kingdom, China, Sweden and the United Arab Emirates to follow in 2021. By the following year, “tens of millions” of 5G handsets will be sold, reaching the low single digits as a percentage of total handset sales, the report said.

“5G network plans have developed well in 2016, driving an ecosystem which will put seven percent of mobile connections on 5G networks by 2025,” Strategy Analytics Senior Analyst Guang Yang said. “China’s 2020 5G launch plans brings it closer to early adopters in the U.S., South Korea and Japan, who are speeding up progress to meet the broadband access demands from the Olympic Games and competition of non-traditional players. In contrast, European operators are currently paying more attention to opportunities in IoT.”

Strategy Analytics said initial trial 5G handsets are expected to run into a few issues as they develop, including a short battery life, a lack of 4G handover or spotty connectivity. However, these issues should be mostly ironed out by the time 2020 rolls around, the report said.

Still, high price tags are expected for the first commercial 5G handsets, Strategy Analytics said.

By 2025, Strategy Analytics said 5G connections are forecast to reach 690 million and 5G handset shipments will surpass 300 million in the same timeframe.