Ericsson, the primary vendor, said in a statement its contract is worth 12.5 billion Swedish crowns ($1.3 billion).
In a separate release, Nokia did not disclose the financial details of its partnership but said the deal marks its return as Vodafone and Three's supplier in the UK.
Nokia will provide its radio access network (RAN) and core networks equipment to about 7,000 sites in the country.
In June, Vodafone and CK Hutchison completed the merger of their UK operations, creating a new business called VodafoneThree and laid out plans to invest 11 billion pounds ($14.8 billion) over 10 years to build one of Europe's most advanced 5G networks.
Ericsson will introduce new 5G radio products into the VodafoneThree network, comprising AI and energy-optimized hardware and smart antennas, aimed at providing customers in London, Edinburgh, Cardiff and Belfast with significantly enhanced data speeds, the company said.
The European contract is a boost for the two Nordic rivals, which are both wrestling with a general market slowdown and the impact of tariffs on their profit in the United States.
($1 = 9.3869 Swedish crowns)
($1 = 0.7431 pounds)