Key takeaways
Radio spectrum is the range of electromagnetic frequencies used to carry wireless communications -- mobile calls and data, Wi-Fi, broadcasting, GPS, emergency services, and much more. Spectrum is a finite natural resource; without careful management, different uses would interfere with each other.
Ofcom is the UK's spectrum regulator. Under the Wireless Telegraphy Act 2006, Ofcom manages the UK's radio spectrum: it allocates spectrum to different uses, licenses specific users, runs spectrum auctions, and enforces against unlicensed or interfering transmissions.
The most commercially significant spectrum management in recent years has been the 5G spectrum awards. In 2026, Ofcom awarded more than 5 GHz of millimetre wave (mmWave) spectrum for mobile use, which can dramatically increase capacity in dense urban hotspots. Ofcom is also developing proposals for the 6 GHz band.
Not all spectrum requires a licence. Wi-Fi operates in licence-exempt bands (2.4 GHz and 5 GHz) where anyone can transmit without an individual licence, subject to technical standards. This is why Wi-Fi works without regulatory approval but must operate within defined power limits.
Ofcom is exploring spectrum sharing -- allowing multiple users to share the same frequencies rather than exclusively allocating them -- as a way to accommodate growing demand, particularly for 5G in rural areas and for private networks.
Reviewed: June 2026Key facts
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What radio spectrum is
Radio spectrum is the part of the electromagnetic spectrum used for radio communications -- the range of frequencies from around 3 kilohertz to 300 gigahertz. Different frequencies have different propagation characteristics: lower frequencies travel further and penetrate buildings better; higher frequencies carry more data but have shorter range. This means different frequency bands are suited to different uses.
Spectrum is a finite, shared natural resource. Unlike, say, a software application that can be copied without limit, spectrum is physically constrained -- there is only so much electromagnetic spectrum available. If two transmitters use the same frequency in the same area at the same time, they interfere with each other and both become useless. This is why spectrum management exists: to coordinate who can use which frequencies, where, when and at what power level.
Ofcom's role as spectrum regulator
Ofcom is the UK's spectrum regulator under the Wireless Telegraphy Act 2006. Its spectrum management functions cover: allocating spectrum to different uses (mobile, broadcasting, emergency services, aviation, satellite, Wi-Fi and so on); issuing licences to specific users to transmit on specific frequencies; running competitive auctions when demand for spectrum exceeds availability; and enforcing against unlicensed or interfering transmissions.
Ofcom's spectrum assurance vehicles -- mobile units equipped with signal measurement equipment -- travel UK roads in England, Scotland and Wales to measure signal strength across frequency bands. This data is used to monitor compliance and identify interference. Ofcom publishes spectrum measurement data from these vehicles.
The 5G spectrum awards
The most commercially significant spectrum management activity in recent years has been the allocation of spectrum for 5G mobile networks. Multiple UK spectrum awards have taken place since 2018, covering frequencies from the 700 MHz band (excellent rural coverage) through the 3.4-3.8 GHz 'C-band' (the main 5G deployment band) to millimetre wave frequencies.
In 2026, Ofcom awarded more than 5 GHz of millimetre wave (mmWave) spectrum across the 26 GHz and 40 GHz bands for mobile use. mmWave spectrum can deliver extremely fast speeds and very high capacity in dense areas -- city centres, transport hubs, stadiums -- because the very high frequencies allow large amounts of data to be carried. However, mmWave has very short range and poor building penetration, making it a complement to, not a replacement for, mid-band 5G.
The 6 GHz band consultation
In 2026, Ofcom is developing proposals for the upper 6 GHz band (6-7 GHz), considering how to share this spectrum between mobile 5G services and Wi-Fi 6E (the latest Wi-Fi standard using the 6 GHz band). The upper 6 GHz band is large -- about 1.2 GHz of spectrum -- and is extremely valuable for both mobile capacity and Wi-Fi performance. Ofcom's approach to this band will significantly affect both indoor Wi-Fi speeds and 5G network capacity over the coming decade.
Ofcom is pioneering an approach where the band is shared between mobile and Wi-Fi using automated frequency coordination (AFC) technology, which manages interference dynamically. This is a more sophisticated approach than simply dividing the band between the two uses and could maximise the value delivered from this scarce resource.
Licence-exempt spectrum and Wi-Fi
Not all spectrum use requires an individual licence from Ofcom. Certain frequency bands are designated as licence-exempt -- anyone can transmit in them without obtaining a licence, provided they use equipment that meets the relevant technical standards and operate within defined power limits. The most important licence-exempt bands are the 2.4 GHz and 5 GHz bands used by Wi-Fi.
This is why you can set up a Wi-Fi router at home without asking Ofcom for permission. The licence-exemption system allows the proliferation of wireless devices (Wi-Fi routers, Bluetooth headphones, baby monitors, smart home devices) without creating an administrative burden on Ofcom or device owners. However, the power limits and technical standards that apply to licence-exempt devices are set by Ofcom and the government to prevent interference with other users.
Spectrum sharing and private networks
A growing area of Ofcom spectrum policy is spectrum sharing -- allowing multiple users to access the same frequency bands simultaneously, managed dynamically to prevent interference. Ofcom has made it easier for enterprises to deploy private mobile networks using shared spectrum. A manufacturer, for example, might deploy a private 5G network in a factory using spectrum shared with public mobile networks in a coordinated way.
Ofcom is also exploring spectrum sharing for rural 5G deployment, where the commercial case for dedicated spectrum is weaker. Sharing arrangements could allow multiple operators to pool spectrum in rural areas, reducing the cost per operator while still delivering coverage.
Related guides
Disclaimer: This guide is for informational purposes only. Kael Tripton Ltd is not regulated by the FCA. Information sourced from Ofcom, legislation.gov.uk and GOV.UK. Verify at ofcom.org.uk.
Frequently asked questions
What is radio spectrum?
Radio spectrum is the range of electromagnetic frequencies used for wireless communications -- mobile phones, Wi-Fi, broadcasting, GPS, emergency services and much more. Different frequencies have different characteristics: lower frequencies travel further and penetrate buildings better; higher frequencies carry more data but have shorter range. Spectrum is a finite natural resource that requires management to prevent interference between users.
Who manages the UK's radio spectrum?
Ofcom manages the UK's radio spectrum under the Wireless Telegraphy Act 2006. It allocates spectrum to different uses, issues licences, runs spectrum auctions, and enforces against unlicensed or interfering transmissions. Ofcom's spectrum assurance vehicles measure signal strength across UK roads to monitor compliance.
Do I need a licence to use Wi-Fi?
No. Wi-Fi operates in licence-exempt frequency bands (2.4 GHz and 5 GHz) where anyone can transmit without an individual licence, provided they use equipment meeting relevant technical standards and operate within defined power limits. This is why Wi-Fi routers, Bluetooth devices and smart home products can be used without regulatory approval -- though the power limits are set by Ofcom.
What is mmWave 5G spectrum?
Millimetre wave (mmWave) spectrum is very high frequency spectrum above 24 GHz. It can deliver extremely fast speeds and very high data capacity in small areas, making it ideal for dense urban hotspots like city centres, stadiums and transport hubs. However, mmWave has very short range and poor building penetration. In 2026, Ofcom awarded more than 5 GHz of mmWave spectrum for mobile use.
What is the 6 GHz band?
The 6 GHz band (technically 5.925-7.125 GHz) is a large block of spectrum that Ofcom is developing proposals for in 2026. It is being considered for sharing between mobile 5G services and Wi-Fi 6E, using automated frequency coordination (AFC) technology to manage interference dynamically. The band could significantly increase Wi-Fi speeds and 5G network capacity.
What is spectrum sharing?
Spectrum sharing allows multiple users to access the same frequency bands simultaneously, managed by technology to prevent interference. Ofcom has made it easier for enterprises to deploy private 5G networks using shared spectrum, and is exploring sharing arrangements for rural 5G deployment where the commercial case for exclusive spectrum allocation is weaker.
How does Ofcom enforce spectrum rules?
Ofcom uses spectrum assurance vehicles equipped with signal measurement equipment to monitor compliance with spectrum rules on UK roads. It investigates reports of interference and can take enforcement action against unlicensed transmissions. Illegal spectrum use -- including signal boosters not approved by Ofcom -- can result in fines, equipment seizure and prosecution.
What spectrum is used by 5G in the UK?
UK 5G networks use several spectrum bands: 700 MHz and 800 MHz (wide area coverage), 3.4-3.8 GHz C-band (main 5G deployment band balancing coverage and capacity), and millimetre wave (24-40 GHz) for high-capacity hotspots. Ofcom awarded the mmWave spectrum in 2026. The 1.4 GHz band is planned for future 5G capacity enhancement over wider areas.
