2 million of the 51 million Koreans bought 5G phones in the first four months and 5 million are expected by the end of 2019. KT forecasts 30% will go 5G by the end of 2020. The only other reliable figure for 5G phones sales is from Huawei, which sold 1 million phones in the first two weeks. Everything else is speculation, usually from limited information. 

From SK, the #1 mobile carrier: We believe that the 5G subscriber mark -- number will exceed the 1 million mark during August and we see that the -- by the end of this year, we will achieve at least 2 million. So it is indeed increasing at a faster pace than we had first expected. And in 2020, considering current trends continue, we expect that number to reach 7 million subscribers.

From KT:  By the end of year 2019, we will see about 10% of 5G subscribers out of its total handset subscribers. And also in light of the broadening of the handset and device lineup and the stabilization of the network, we expect to reach around 30% by 2020.