New reports are predicting 5G services to have 25 million subscriptions globally by the end of 2021, primarily for fixed and mobile broadband services.

According to Ovum's latest 5G subscription forecast, 5G will launch in 2020 and be available in every major region worldwide in 2021, with the analyst firm forecasting that there will be more than 50 operators offering 5G services in close to 30 countries by the end of 2021.

The majority of 5G subscriptions will be concentrated in a handful of leading 5G markets, Ovum says, namely the United States, China, Japan and South Korea.

The US will be the largest 5G market in 2021, with more than 10 million 5G subscriptions, followed by China, Japan, and South Korea. Those top four 5G markets will account for more than 80% of the world's 5G subscriptions in 2021, Ovum says.

Major operators such as Verizon, SKT, and Telia have announced plans to launch pre-standard 5G services as early as 2018, with plans to transition to standardised services once the 5G standard is finalised.

Ovum says early launches of pre-standardised 5G services could help these operators establish a lead in 5G, but could also create challenges around upgrading pre-standard equipment and services to the 5G standard.

Ovum forecasts that US-based Verizon will be the largest 5G operator by subscriptions in 2021, followed by its rival AT-T, NTT DoCoMo in Japan, and China Mobile.

Driven by the early major 5G investments of leading operators, North America and Asia will each account for close to 45% of global 5G subscriptions at the end of 2021, followed by Europe with more than 10% of subscriptions, with the Middle East and Africa accounting for the remainder, the forecast shows.

Ovum says the main use case for 5G through 2021 will be enhanced mobile broadband services, although fixed broadband services will also be supported, especially in the US.

Over time, 5G will support a host of use cases, including the Internet of Things and mission-critical communications, but Ovum says it does not believe those use cases will be supported by standardised 5G services through 2021.

A number of operators have announced plans to launch what they describe as 5G services before 2020, but according to the analyst firm, these will not typically be based on networks and devices complying with 5G standards, and so are excluded from Ovum's forecasts.