The UK energy market is preparing for significant shifts in non-commodity costs that will directly impact business energy bills over the next 18 months. Here’s what you need to know:
🔹 TNUoS (from Apr 2026)
- Standing charges set to rise sharply — current projections indicate 30–50% increases in TNUoS charges.
- Increases will vary by meter location and banding.
- Draft tariffs due Nov 2025, finalised Jan 2026.
🔹 BSUoS (from Oct 2025)
- Rates increasing 46% from £10.74/MWh (1.074 p/kWh) to £15.69/MWh (1.569 p/kWh).
- Confirmed for Oct 2025 – Mar 2026, with further rises possible.
- Will particularly impact customers on pass-through contracts.
🔹 RAB Levy (from Dec 2025)
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Update – October 2025: The Low Carbon Contracts Company (LCCC) has announced a revision to the Nuclear RAB Interim Levy Rate (ILR).
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The rate has been increased from 0.3455 p/kWh to 0.354 p/kWh.
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The implementation date has moved from 1 November 2025 to 1 December 2025, reflecting a one-month delay to the scheme’s go-live date.
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This change reduces the collection period for the first charging year while the Total Reserve Amount remains unchanged.
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The levy will fund new UK nuclear power projects under the Nuclear Regulated Asset Base (RAB) model.
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Exemptions continue to apply for Energy Intensive Industries (EII) sites.
🔹 REMA (Ongoing)
- Government confirms UK will retain a single national wholesale electricity price.
- Reforms aim to encourage low-carbon investment and improve grid efficiency.
💡 What this means for businesses:
- Energy bills will increase due to regulated charges outside of supplier control.
- Clients on pass-through contracts will feel the most immediate impact however suppliers may reserve the right to reconcile costs on fixed contracts.
- Budgeting and contract planning should take account of these changes now.
- Suppliers are yet to confirm fully how these costs will be shown on invoices, it is likely TNUoS & BSUoS will impact standing charges, RAB may be shown as an additional line on your bill or included in the unit rate / standing charge.
📊 We’ll continue to monitor supplier updates and regulatory publications and share insights as the final tariffs are confirmed.