On 1 April 2026, TNUoS charges rose by up to 64% on average, with some individual bands rising by more than 100%. For many commercial sites, the result was thousands of pounds per year in additional standing charges.
In this guide, we explain how the market works and how you can take part in it.
What do the 2026/27 TNUoS charges mean for your business?
You’ll now pay a higher fixed daily charge based on its TNUoS residual band across all of your sites with the average increase being 64%.
For example, the estimated annual charge for:
- An LV1 site, which rose from £1,426 to £2,116
- An HV2 site, which went up from £22,922 to £42,761
- An EHV2 site, now an estimated £423,174, up from £270,752
Most businesses can’t reduce their TNUoS charge by using less electricity or changing what times they draw electricity from the grid. Instead, you should check that each of your meters is in the correct band and that your supplier has applied the right rate to all of them.
What is your 2026/27 TNUoS rate?
Find your site’s residual band in the table below which shows you the daily rate, estimated annual charge, and increase from 2025/26.
2026/27 TNUoS demand residual rates by band
Methodology: 2025/26 final rates and 2026/27 final rates and current thresholds are from NESO’s official tables. Annual figures use 365 days and are rounded to the nearest pound. The table excludes VAT, supplier treatment and locational TNUoS. The 28% to 116% range and 64% weighted average are from Drax’s analysis of NESO’s final tariffs.
| Connection | Band | Current threshold | 2026/27 daily rate | Estimated annual charge | Increase from 2025/26 |
|---|---|---|---|---|---|
| LV, no MIC | LV_NoMIC_1 | Up to 3,986 kWh | £0.239315 | £87 (was £57) | £31 (up 54.6%) |
| LV, no MIC | LV_NoMIC_2 | Over 3,986 to 13,677 kWh | £0.587299 | £214 (was £134) | £81 (up 60.4%) |
| LV, no MIC | LV_NoMIC_3 | Over 13,677 to 27,543 kWh | £1.242416 | £453 (was £278) | £176 (up 63.3%) |
| LV, no MIC | LV_NoMIC_4 | Over 27,543 kWh | £3.461015 | £1,263 (was £755) | £508 (up 67.3%) |
| Low voltage | LV1 | Up to 90 kVA | £5.797398 | £2,116 (was £1,426) | £690 (up 48.4%) |
| Low voltage | LV2 | Over 90 to 150 kVA | £11.511840 | £4,202 (was £2,383) | £1,819 (up 76.3%) |
| Low voltage | LV3 | Over 150 to 250 kVA | £14.381374 | £5,249 (was £3,742) | £1,507 (up 40.3%) |
| Low voltage | LV4 | Over 250 kVA | £38.180103 | £13,936 (was £8,300) | £5,636 (up 67.9%) |
| High voltage | HV1 | Up to 500 kVA | £31.839048 | £11,621 (was £7,968) | £3,653 (up 45.8%) |
| High voltage | HV2 | Over 500 to 1,100 kVA | £117.152788 | £42,761 (was £22,922) | £19,839 (up 86.6%) |
| High voltage | HV3 | Over 1,100 to 2,000 kVA | £185.418505 | £67,678 (was £44,455) | £23,222 (up 52.2%) |
| High voltage | HV4 | Over 2,000 kVA | £528.912335 | £193,053 (was £115,923) | £77,130 (up 66.5%) |
| Extra-high voltage | EHV1 | Up to 3,500 kVA | £325.476550 | £118,799 (was £58,679) | £60,120 (up 102.5%) |
| Extra-high voltage | EHV2 | Over 3,500 to 11,000 kVA | £1,159.381475 | £423,174 (was £270,752) | £152,422 (up 56.3%) |
| Extra-high voltage | EHV3 | Over 11,000 to 20,000 kVA | £2,512.930533 | £917,220 (was £575,325) | £341,895 (up 59.4%) |
| Extra-high voltage | EHV4 | Over 20,000 kVA | £5,698.386405 | £2,079,911 (was £1,417,199) | £662,712 (up 46.8%) |
| Transmission connected | T-Demand1 | Up to 25,131 MWh | £1,401.949529 | £511,712 (was £236,446) | £275,265 (up 116.4%) |
| Transmission connected | T-Demand2 | Over 25,131 to 64,451 MWh | £2,931.228837 | £1,069,899 (was £834,990) | £234,909 (up 28.1%) |
| Transmission connected | T-Demand3 | Over 64,451 to 163,880 MWh | £7,586.413858 | £2,769,041 (was £1,987,929) | £781,112 (up 39.3%) |
| Transmission connected | T-Demand4 | Over 163,880 MWh | £20,829.236682 | £7,602,671 (was £4,670,801) | £2,931,870 (up 62.8%) |
The final rates and current thresholds come from NESO’s 2026/27 tariff publications. The 28% to 116% range and 64% average come from Drax’s analysis of those final tariffs.
Four ways your business can reduce its TNUoS charge
Most of your TNUoS charge comes from the demand residual, which is a fixed daily charge based on your site’s band.
Using less electricity for a few hours, changing when you use electricity, reducing one demand peak, or charging a battery overnight won’t bring the charge down.
But you may still be able to save on the charge by taking the following four steps.
1. Check that each site is in the correct band
Ask your supplier to confirm in writing which band it has used for each site and the capacity or consumption figure they based that decision on.
As well as changing the pricing, NESO, the organisation which sets the charges, introduced new band thresholds on 1st April 2026. That means your site may now fall into a different band even if its capacity or annual consumption hasn’t changed, so don’t assume last year’s band still applies.
Please be aware however that this check may reveal undercharging as well as overcharging.
2. Check whether your agreed capacity is still right
DNOs (or Distribution Network Operators) place some low-voltage, high-voltage, and extra-high-voltage sites into bands using their Agreed Supply Capacity, or ASC. ASC is the maximum amount of power your site is allowed to draw from the local network at any one time.
If your ASC is higher than your site will need over the long term, ask your DNO to reduce it. If they approve a lower capacity, that could mean they move your site into a cheaper band.
Think of capacity over the course of a year instead of a month or two, when your site may be quieter or there may be an unusually low peak. You still want to make sure your site has all the capacity it needs for machinery, EV charging, heat pumps, expansion, and periods when a battery or other equipment isn’t available.
Your DNO must approve any change.
3. Check how your supplier bills you for the TNUoS charge
Your supplier may include your TNUoS in your standing charge or another part of your tariff, pass it through separately, or recalculate it later and add or subtract the difference on a future bill. They may not show it as a separate line.
Ask the supplier to show you:
- The demand residual
- The smaller locational charge
- Other network costs
- Administration charges
- VAT
You can then multiply the published daily rate for your band by the number of days covered by the bill and check whether it matches the demand residual element of the TNUoS your supplier has charged you.
4. Check whether you can reduce the locational charge
The locational charge is the smaller part of TNUoS and varies by where your site is and when it uses electricity.
For half-hourly sites, it is based on demand during three peak periods in winter, known as triads. For non-half-hourly sites, it is linked to weekday electricity use between 4pm and 7pm.
Reducing demand at these times may bring down this part of your TNUoS charge. However, the savings on offer are much smaller than any reduction to your fixed demand residual.
Control TNUoS costs with GridVolt
GridVolt can’t reduce your fixed TNUoS demand residual overnight. But by using our software, you can cut other electricity costs in the short term and may be able to reduce your agreed capacity and move into a cheaper TNUoS band in the longer term.
Here’s how. Our Energy Manager software uses an on-site controller connected to your battery and inverter to decide when your battery should charge, discharge, or hold electricity back for later use.
It updates its forecasts 96 times a day using your tariff, site demand, solar generation, and operating needs. It then recalculates the battery schedule and chooses the action expected to save your business the most money, without ever leaving you short of the power your site needs.
For suitable sites in Great Britain, GridTrade uses spare battery capacity for wholesale electricity trading. The income can help offset rising TNUoS and other energy costs.
To find out more, fill in the form on the right or get in touch via the contact page.
Frequently asked questions about TNUoS charges
What are TNUoS charges?
TNUoS charges help pay for the upkeep and improvement of the national electricity transmission network across England, Scotland, and Wales. NESO charges this work to electricity suppliers and they recover those costs through your electricity bill.
Northern Ireland uses a different electricity market and charging system.
What is the TNUoS demand residual?
The demand residual is the fixed daily part of your TNUoS charge. Your site pays it every day it stays connected to the grid, and the amount depends on its band. Using less electricity for a day or moving some use to a cheaper time won’t reduce it. It will only fall if your site later moves into a lower band because its long-term power needs or annual electricity use have dropped.
How is your TNUoS band decided?
For low-voltage sites without a Maximum Import Capacity, the band is based on annual electricity use. Maximum Import Capacity is the highest level of power your site is allowed to take from the electricity network at one time.
Most other low-voltage, high-voltage, and extra-high-voltage sites are placed into bands using their Agreed Supply Capacity (ASC). ASC is the maximum amount of power the connection has been agreed to provide.
Transmission-connected sites are large sites connected directly to the national transmission network and they use separate consumption thresholds.
The limits for each band changed on 1 April 2026. This means your site may now be in a different band even if its capacity or annual electricity use hasn’t changed. If it moved into a higher band, your daily charge will have risen by more than the standard increase for its old band.
Why did TNUoS charges rise in 2026/27?
NESO raised TNUoS tariffs in 2026/27 to generate more cash from customers. The amount targeted is £7.61 billion, up from £5.1 billion in 2025/26.
This is to pay for increased costs and revenue allowances for the companies that own and operate the transmission network under the new price-control period, known as RIIO-ET3.
These companies also need to invest in cables, substations, and other equipment as more electricity is generated far from the homes and businesses that use it.
Why might your electricity bill not match the published rate?
The published TNUoS rate for your band covers only the fixed demand residual. Your electricity bill may also include the smaller locational part of TNUoS, other network costs, administration charges, and VAT.
Your supplier may group these under terms such as “pass-through charges,” “third-party charges,” or “non-commodity charges.” It may include TNUoS in your standing charge, show it separately, or recalculate it later and add or subtract the difference on a future bill.
Ask your supplier to confirm your band, daily demand residual rate, and any additional amounts separately.
What is the locational part of TNUoS?
The locational charge is the smaller part of TNUoS, and how it is calculated depends on how your site’s electricity use is measured.
For half-hourly sites, it can depend on demand during three winter peaks, known as triads. Some northern demand zones have a zero tariff. For non-half-hourly sites, it is linked to electricity used between 4pm and 7pm each day.
Reducing demand during the relevant periods may lower this charge, although the saving is usually much smaller than the fixed demand residual.
What is the difference between TNUoS and DUoS?
TNUoS pays for the national high-voltage transmission network while DUoS pays for the local distribution network that carries electricity from the transmission system to your site.
You can influence the level of DUoS charges by changing when and how much electricity your site takes from the grid. That means you have more scope to reduce the DUoS charge than the fixed TNUoS demand residual.
Should you reduce your Agreed Supply Capacity?
You can reduce your Agreed Supply Capacity, but make sure you base any decision to reduce it on at least 12 months of demand data and factor lasting spare capacity into your future plans.
You also need to be certain that a lower capacity won’t affect your business operations. Check how much capacity you’ll need for planned machinery, EV charging, heat pumps, expansion, and what would happen if, for whatever reason, your battery was unavailable.
If you are already using peak shaving, your level of actual maximum demand could already be well below your agreed capacity, a point you should raise with your DNO when requesting a review.
Will TNUoS charges rise again in 2027/28?
NESO currently expects demand residual tariffs to rise by another 21% on average in 2027/28. These rates aren’t final, but you can use them as planning figures when preparing internal budgets. Update your budget when NESO publishes the final tariffs so it reflects what your business will actually pay.
Do TNUoS charges apply in Northern Ireland?
No. TNUoS applies only to sites in Great Britain, meaning England, Scotland, and Wales. Northern Ireland is part of the Single Electricity Market (SEM) with the Republic of Ireland and SEM uses a different charging framework.
How do TNUoS charges affect businesses with several sites?
Each site your supplier charges separately has its own daily demand residual charge. If your business has ten separately charged sites, it will pay ten daily charges.
Check the band and rate for each site. Don’t assume every site has gone up by the same amount, as they may have different connections, power limits, and bands.