From 01 April 2026, non-domestic electricity customers will see significant increases in their Transmission Network Use of System (TNUoS) charges. These are the fees that cover the cost of maintaining and upgrading the UK’s high-voltage transmission network.
The increases are substantial, and they’re causing uncertainty across the sector. Some suppliers are even reopening fixed contracts to pass these costs through to customers.
Here’s what’s happening and what it means for your organisation.
TNUoS charges pay for the UK's electricity transmission network - the infrastructure that moves electricity across the country. These costs cover building and maintaining the network, investment in new infrastructure, and regional and usage-based costs.
The UK is undergoing the largest upgrade to its electricity grid in decades, including connecting new renewable energy sources like offshore wind, reinforcing the network to handle increasing demand, and ensuring long-term stability.
This has resulted in large cost increases for 2026-2031.
What does this mean for your bills?
Standing charges will rise and the increases vary significantly depending on:
- Where you are in the UK (region)
- Your voltage level (high voltage customers see larger increases)
- How much electricity you use (higher demand = higher impact)
This affects all non-domestic customers. From small charities with a single site to large organisations with multiple high-voltage connections - everyone will see increases, though the scale varies widely.
What should you do?
- Check your contract terms and see if it's truly fully fixed
- Ask your supplier or broker for the total financial impact on your organisation
- Factor the increases into your budgets
Support is available
Utility Aid is here to help
Call: 0808 1788 170
E-mail: [email protected]
Click here to visit their website.
