10 things to check before signing a solar installation contract

Compare the contract with the quote you already have. Check that the equipment, work, price and savings match what you were told. MCS has extra commitments for some certified installers, but the protections that apply depend on the installer and your agreement.

1. Who are you making the agreement with? Check the company name and contact details on the quote and contract. If the installer says it is MCS certified (part of an industry standards scheme), check the company on the MCS directory too. Certification does not replace reading your contract.
2. What will be installed? Check the number and size of the panels, the roof layout, the inverter and whether a battery is included. Ask what may change after a roof survey.
3. How much electricity is it expected to make? Ask for the yearly estimate and what it is based on, including your roof’s direction, shade and location. Ask what could make the result lower.
4. Are the equipment models named? Check the make and model of the panels, inverter and battery. Ask the installer to get your written agreement before changing them.
5. Are the battery and its warranty clear? If there is a battery, check how much electricity it can store and how quickly it can charge or supply power. Read what each warranty covers, what it excludes and who provides it.
6. What is the full price? Check the cash price, what it includes, possible extra work and when payments are due. For finance, compare the deposit, interest, fees and total amount to repay, not only the monthly cost.
7. How were the savings worked out? Ask which electricity price and export payment were used. In Great Britain, export payments depend on the supplier and your eligibility. Northern Ireland has different arrangements. Do not assume a quoted rate is available to you.
8. Who does what, and when? Confirm the survey, installation and handover dates. Ask who handles permissions and network steps, and what happens if there are delays or design changes.
9. What will you receive when the work is done? Ask which checks, settings, certificates, manuals and monitoring access you will get. Find out who to contact if there is a fault.
10. Have you read the contract and cancellation terms? Read the terms on deposits, changes, delays, cancellation, warranties and complaints. A cooling-off period does not apply in the same way to every contract. If you are unsure, get independent consumer or legal advice before signing.

Do not rely on the headline payback alone

Ask how much of the saving comes from using solar power at home and how much from selling extra power. Check the electricity prices used and how the battery changes exports. Future prices, your use and the amount your panels make can differ from the estimate.

Use the solar payback calculator to explore how long the savings could take to cover the price, or the battery savings calculator to compare the same panels with and without storage. These tools use examples. Your installer still needs to assess your home.

Be careful with cancellation assumptions

A cooling-off period can apply to some contracts made by phone, online or in your home. The rules depend on how the agreement was made, what work is involved and whether you asked for work to start early. If you have accepted a quote, do not assume you can cancel for free. Read your contract and get advice about your situation.

Use the checklist on the quote you have

Check your solar quote for free to organise the price, equipment and details in your proposal. Fairbeam cannot check whether your roof is suitable, judge installation quality or verify a forecast for your home.

Sources and further guidance

• MCS Customer Commitment (2025): commitments that apply to MCS-certified installers for relevant certified installations.
• MCS Guidance for Contracts and Quotations (2026): clear scope, costs and terms.
• CMA consumer guide to buying green heating and insulation products: practical consumer checks and rights.
• Citizens Advice: cancelling building or decorating work: how cancellation can depend on where and how the contract was arranged.
• Energy Saving Trust: rooftop solar installation and Ofgem: Smart Export Guarantee.

Sources checked 20 October 2026. This checklist is general information, not legal advice. Ask a qualified adviser about your contract or rights.