Its 5G network is now available in over 400 locations and across more than 3,000 sites.
The operator adds that it has made improvements to its network to support “major growth” in customer data consumption which now stands at almost 20GB per month, up 15% year-on-year.
Usage on Three’s 5G home broadband network has also reached 354GB per month.
David Hennessy, Chief Technology Officer, Three UK, said: “We are relentlessly focused on delivering the UK’s biggest and fastest 5G network for the UK.
“Millions of mobile, business and home broadband customers across more than half the UK’s population are able to access our superfast speeds enabling them to live their digital lives to the fullest.”
The government has aims for 5G to be available to most of the UK population by the end of 2030.
Three UK recently announced it would be switching off its 3G network in 2024, while industry sources hailed it as the “right move”.
This will allow for advanced uses as its 5G rollout continues to gather pace.
The operator has also been in talks with Vodafone over a potential merger between the two companies.