Commercial solar financing in 2026: what lenders check before they say yes

A green loan, hire purchase or asset-finance decision on a commercial solar array is a credit decision about the business first and the array second. The base cost of money is Bank Rate — 3.75%, held at the decision published on 17 September 2026 with the next due on 5 November — and the lender adds a margin for the risk it reads in the file. The routes themselves are compared on the commercial solar financing page; this post is about the file. For a side-by-side view of who lends against a solar array, see our solar lending comparison.

The five documents credit teams read first

• Two years of filed accounts (three for larger facilities), plus management accounts if the last filing is more than six months old. Profitability in at least two of the last three years and positive net assets are the common floors.
• Half-hourly consumption data. It proves the site can use the generation; a lender reads self-consumption as the quality of the saving the loan is repaid from.
• The DNO connection offer. Above 16 A per phase the array needs a G99 application; an offer with an export limit is part of the economics, and most lenders make the finance offer conditional on it.
• A structural survey and the installer's itemised quote. The plant cost is what the allowances and the security attach to; building works are separate.
• Evidence of tenure. Freehold, or a lease that outlasts the finance; a tenant on a short lease is steered to an operating lease or a landlord-funded array.

Three rules that shape the offer

The Growth Guarantee Scheme. Through accredited lenders the government guarantees 70% of a qualifying facility, with the business remaining 100% liable; term loans and asset finance run from three months to six years, up to £2m per business group, with upfront fees capped at 5% and no charge over a director's principal private residence. On 12 July 2026 the Chancellor announced extra capacity, terms of up to ten years and a higher turnover limit, which lenders are adopting; ask whether a solar facility is being written under the scheme. On the tax side, interest on a business solar loan is normally deductible on top of the capital allowances.

The consumer-credit perimeter. Credit over £25,000 wholly or predominantly for business purposes is outside the regulated consumer-credit regime; a sole trader or small partnership borrowing less than that is a regulated customer, which changes the paperwork and the lender's appetite.

Who owns the plant. A loan or hire purchase leaves the capital allowances with the business; a lease or PPA moves them to the funder, which prices some of their value into the rental. Lenders read the route as part of the credit: an owner with the allowances has a stronger year-one cash position than a lessee.

Why applications fail

Declines tend to cluster around four causes: accounts that show a loss with no recovery plan (the allowances have no profit to offset); a lease shorter than the term; an array sized to the roof rather than to demand, so the saving the lender is lending against is mostly export at 3p–15p a unit; and a missing or conditional connection offer. All four are fixable before the application goes in, and none is fixed by a better monthly quote.

Read next: commercial solar financing: all six routes compared and the commercial solar finance companies guide for who writes each route.