TNUoS Explained

TNUoS Explained: Why UK Business electricity costs are rising in 2026 – What does your business need to Know? 

From April 2026 many UK businesses will notice an increase in a charge on their electricity bill called TNUoS. 

It’s not a supplier fee, and it’s not something energy companies set. It’s a national network charge, and it’s increasing across the UK. 

So what is it, why is it rising, and what does it mean for your business? 

What Is TNUoS? 

TNUoS stands for Transmission Network Use of System.

Put simply, it’s the cost of using the UK’s high-voltage electricity network – the infrastructure that moves power from where it’s generated to the local networks that supply your business.

These charges help fund things like: 

• Maintaining electricity transmission lines 
• Upgrading the national grid 
• Connecting new renewable energy sources 

The charges are managed nationally by the National Energy System Operator (NESO) and apply to ALL electricity users across the country. 

How is TNUoS calculated?  

Total TNUoS cost consists of two charging elements:  

1 – Locational: Cost is based upon your consumption and Grid Supply Point (GSP) rate published by NESO. The charged rate differs based upon your meter type (i.e., Half Hourly and Non-Half Hourly) 

2 – Non-Locational (Residual): This is a fixed charge which is calculated based on a £/day rate differing based on meter type.  

Why Are These Charges Going Up? 

The UK’s electricity system is changing quickly.  More renewable energy is being connected to the grid, and the network needs major upgrades to support growing electricity demand and to support the transition to cleaner energy.  Because of this, billions are being invested in the transmission network. 

Over the next 12 months, the total cost collected through TNUoS charges is expected to reach £7.6 billion, a 61% increase compared to the previous year.  

What does this mean for your business? 

For many businesses, network charges already make up part of your electricity bill, and TNUoS accounts for around 7% of the total cost depending on the type of electricity connection your business has.  Businesses with larger or higher voltage connections may see a bigger impact. 

One Important Thing to Know 

Unlike most parts of your energy bill, TNUoS charges are mostly fixed.  So, using less electricity doesn’t necessarily reduce this part of your bill. 

Instead, the charge is based on factors like: 

• The type of meter your business has 
• Your connection to the network 
• The band assigned by your local network operator 

What Should Businesses Do? 

While these charges are set nationally and can’t be avoided, there are a few simple steps businesses can take:

1 – Review your energy contract – Make sure future network cost increases are considered when you are renewing. 

2 – Understand your charges – Knowing how network costs work helps you to plan ahead. 

3 – Plan your energy budget early – With network investment increasing, these costs will remain part of future electricity bills, therefore a plan early to help factor these costs. 

The Bottom Line 

The increase in TNUoS charges is part of the UK’s investment in a stronger and cleaner electricity system. 

While this means higher network costs in the short term, the upgrades will support a more reliable energy grid and the transition to renewable energy.  Understanding these changes now can help businesses plan ahead and avoid surprises in future energy bills. 

For more information about TNUoS, how it is calculated, understanding which band your meter falls and the potential future trends these changes could mean for your business, head over to our FAQ section now.