2026 Business Rates Revaluation: The Honest Impact on Factory Solar
The Valuation Office Agency's 2026 revaluation lifted rateable values for solar PV assets on commercial property by approximately 51% in England and Wales. We explain exactly how much extra a typical factory pays, the reliefs that blunt the uplift, and why solar is still the most profitable capex decision a UK manufacturer can make this year.
What Changed in April 2026
On 1 April 2026 the new rating list came into force in England and Wales. The VOA reassessed rooftop and ground-mount solar PV as a distinct Plant & Machinery hereditament and updated the reference build costs used in the contractor's basis valuation. Average rateable values for commercial solar rose approximately 51% from the 2023 list.
Scotland and Northern Ireland follow separate assessment cycles. The Scottish Assessors Association published its own 2026 practice note with a broadly similar uplift; Land & Property Services in Northern Ireland maintains its 2023 list.
The standard multiplier in England for 2026-27 is 54.6p in the pound. Rateable value multiplied by this figure gives the annual rates charge before reliefs.
Worked Example: 500 kWp Factory Rooftop System
- Pre-2026 rateable value (2023 list): ~ £8,500
- Annual rates at 51.2p multiplier: ~ £4,350
- Post-2026 rateable value (2026 list): ~ £12,850
- Annual rates at 54.6p multiplier: ~ £7,015
- Annual uplift: ~ £2,665
- Annual system energy saving (at 25p/kWh): ~ £110,000
- Net impact on payback: +0.26 years
The revaluation adds real cost, but it is dwarfed by the underlying energy saving. For most systems the change extends payback by 2 to 5 months, not years.
Reliefs That Blunt the Uplift
Improvement Relief
From April 2024, qualifying improvements — including installing solar — attract 100% rates relief on the uplift for 12 months. Your rates stay at pre-solar levels for the first year.
Transitional Relief
Properties seeing large rateable value jumps benefit from capped annual increases over the life of the 2026 list. Mitigates year-one shock.
Small Business Rates Relief
Applies to most single-site SMEs with RV under £15,000 total. Full 100% relief up to £12,000 RV.
Freeport Enhanced Capital Allowances
Sites within the 12 UK Freeport tax zones receive 100% rates relief plus Enhanced Capital Allowances on solar plant — effectively removing both the capex and rates cost.
Full Expensing (Capital Allowances)
From April 2023, companies paying corporation tax can deduct 100% of solar capex in year one. This more than offsets several years of the new rates liability.
Enterprise Zone Rates Discount
Select Enterprise Zones offer up to 100% rates discount (max £55,000/year) for five years. Check your postcode against the current Enterprise Zone register.
Revaluation Impact by System Size
| System Size | Est. 2026 Rateable Value | Annual Rates | Annual Uplift vs 2023 List | Payback Extension |
|---|---|---|---|---|
| 100 kWp | £2,500 | £1,365 | +£520 | +0.2 yrs |
| 250 kWp | £6,250 | £3,413 | +£1,300 | +0.23 yrs |
| 500 kWp | £12,850 | £7,015 | +£2,665 | +0.26 yrs |
| 1,000 kWp | £24,500 | £13,377 | +£5,080 | +0.28 yrs |
| 2,000 kWp | £48,000 | £26,208 | +£9,950 | +0.30 yrs |
Figures illustrative. Actual valuations vary by local authority, installation age and mounting type. Request a verified assessment.
How to Challenge an Over-Assessed Solar Rateable Value
- Check the VOA entry. Search your property on the VOA portal, confirm kWp, install year and mounting type match reality.
- Compare to local peers. Rating surveyors can benchmark your RV against comparable factory installations in your region.
- File a Check. Submit a Check via the VOA 'Check, Challenge, Appeal' system within six months of noticing the discrepancy.
- Challenge. If the Check is rejected, you have four months to file a Challenge with supporting evidence on valuation methodology.
- Appeal to the Valuation Tribunal. Last resort if the Challenge is unsuccessful. Typically resolved within 12-18 months.
Frequently Asked Questions
Why did solar business rates rise in 2026?
The 2026 revaluation lifted rateable values for solar PV assets on commercial property by approximately 51% in England and Wales, reflecting higher construction costs and updated valuation methodology by the Valuation Office Agency.
Does the rates increase change solar payback?
For most factory and warehouse systems, the increase adds a modest annual liability that extends payback by 0.2-0.5 years. The underlying business case remains compelling because grid tariffs have risen proportionally.
Are there reliefs available to offset the rates uplift?
Small Business Rates Relief, Improvement Relief (up to 12 months following qualifying improvements including solar), Transitional Relief and full expensing all help cushion the uplift. Freeport Enhanced Capital Allowances remove the rates burden altogether on qualifying sites.
Does the multiplier apply to solar the same as building rates?
Solar PV is rated separately as plant and machinery using the same standard multiplier (54.6p in England for 2026-27). The uplift comes from the revised rateable value, not the multiplier.
Related Reading
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