The UK has 4 primary, spectrum-holding operators. Ofcom, the UK's telecommunications regulator, can apply bidding restrictions in auctions in order to ensure competition in the market. There are currently 2 spectrum caps in place on operators.
- An overall cap on “immediately usable” spectrum of 255 MHz.
- An overall cap of 340 MHz of total spectrum (37% of that due to be available by mid-2020).
A good visualisation from Ofcom showing the spectrum holdings before the 2017 auction, and how their caps came into effect.
The figure below shows the current UK spectrum allocations for mobile operators, after the 2017 auctions, and shows the spectrum to be auctioned in the early-2020 auctions.
