Best Solar Panel Installers UK 2026: Top Companies Compared

Choosing a solar panel installer is one of the most important decisions in the entire solar journey – arguably more important than which panels you pick. The same 10-panel, 4kW system averages around £6,500 installed across Great Britain, but quotes for it can sit well above or below that depending on who installs it, and the quality of the installation directly affects how much electricity your system generates over the next 25 years. A poorly fitted inverter, inadequate cable management, or substandard mounting hardware can reduce output by 10–20% and cause failures that void manufacturer warranties.

The UK market has expanded rapidly: over 180,000 solar systems were installed in 2024 alone, and the number of MCS-certified installers now exceeds 2,800. This is good news for consumers – more competition drives better pricing – but it also means there are more companies chasing your business, not all of them with the experience or credentials to do the job well. Our shortlist focuses on installers with verifiable track records, strong independent reviews, and genuine UK coverage.

This guide covers the 7 best solar panel installers in the UK, with a comparison table, regional breakdowns, and a detailed section on how to vet any installer before you sign a contract. Before you request quotes, use our savings calculator to estimate what a system would save you. For context on what a quality installation should cost, see our solar panel costs guide.

The 7 Best Solar Panel Installers in the UK (2026)

The best solar panel installers combine MCS certification, strong independent reviews, comprehensive warranties, and transparent pricing. Our top 7 are ranked on customer satisfaction, coverage, installation quality, and after-sales support.

Trustpilot scores and review counts move daily; the figures in this guide were checked on Trustpilot on 9 October 2026. Octopus Energy’s profile covers its whole energy supply business, so we don’t quote it for solar. Always confirm the current score on trustpilot.com before you commit.

Octopus Energy Solar is the UK's largest-scale solar installer, backed by the brand trust that has made Octopus the UK's largest energy supplier. Its Trustpilot profile covers the whole Octopus energy supply business rather than solar installs, so we don’t quote that score here, but the same customer-service operation stands behind the solar arm.

Octopus uses in-house installers where possible and partners with vetted MCS-certified subcontractors where coverage requires it. Their solar systems come with a 25-year panel performance warranty, an advertised 10-year workmanship warranty (confirm it appears in your quote pack), and integration with their Intelligent Octopus Go tariff for EV owners. The ability to manage your solar, battery, EV charger, and energy tariff through one app is a genuine differentiator. Read our dedicated solar panel brand comparison to understand which panels Octopus typically installs.

Heatable built its reputation in the boiler replacement market before expanding into solar, and it has brought the same approach: fully online quoting, fixed prices published on the website, and no hard-sell sales calls. Their Trustpilot profile, which covers the boiler business as well as solar, stands at 4.8/5 from 15,039 reviews (checked 9 October 2026).

What sets Heatable apart is pricing transparency. You can get a fixed-price solar quote online in minutes without speaking to a salesperson – a rarity in an industry still dominated by in-home sales visits. They operate across England and Wales and use a network of vetted, MCS-certified local installers. Heatable publishes its prices: solar installs start from £4,995, and its three 10-panel LONGi packages with battery storage cost £9,155 to £11,815 installed, including VAT (checked 5 October 2026). Scaffolding is not in the online quote and typically adds £800–£950, by Heatable’s own estimate. They are compatible with battery storage add-ons and can bundle EV charger installation at the same time.

Project Solar is one of the UK's longest-established dedicated solar installers, with 7,632 Trustpilot reviews at 4.6/5, rated Excellent (checked 9 October 2026). They focus on residential installations across England and are particularly strong in the Midlands, North West, and Yorkshire regions.

Their pricing starts from approximately £5,500 for a 4kW system, which positions them competitively – pair this with budget panel options and the total outlay can be among the lowest from a credible MCS installer. They offer a range of panel brands and system sizes – understanding which panel type to specify before your survey will help you evaluate the quote – and their surveyors typically visit in person to assess your roof before providing a detailed quote. Workmanship is generally well-regarded in customer reviews, and they offer a 25-year panel warranty with a 5-year workmanship guarantee as standard. A solar battery can be added at installation or retrofitted later.

Solar4Good shares the top Trustpilot score on this list with Heatable at 4.8/5, from a smaller review base of 815 customers (checked 9 October 2026). They operate predominantly in South and West England and have built a loyal customer base through attentive project management and premium component selection.

They are a genuine premium option: systems start from around £6,200 for 4kW, slightly above the market average, but customer reviews consistently highlight the quality of the survey process, installation cleanliness, and responsiveness of their aftercare team. If you are investing in a high-specification system with battery storage and want a white-glove experience, Solar4Good is worth shortlisting alongside one or two other quotes.

Sunsave holds Which? Trusted Trader accreditation – an independent endorsement that goes beyond MCS certification and involves background checks, customer vetting, and ongoing compliance monitoring. For consumers who prioritise verified third-party endorsement, Sunsave is an excellent choice.

They operate across England and offer both solar panel installation and battery storage solutions. Their approach involves a thorough in-home survey followed by a detailed proposal. Systems start from approximately £6,500 for a 4kW system. The Which? Trusted Trader mark provides added recourse if anything goes wrong, which is a meaningful differentiator for a significant home improvement investment.

Glow Green has built a strong reputation in heating installations – boilers and heat pumps – and has expanded significantly into solar over the past three years. Their 4.6/5 from 15,789 reviews (checked 9 October 2026) reflects a company with high operational volume and generally consistent standards.

Their key advantage is the ability to bundle solar panels with a heat pump or boiler replacement, simplifying what would otherwise require coordinating multiple contractors. This is particularly valuable if you are planning a broader home energy upgrade. Solar systems start from approximately £5,800 for 4kW, with heat pump packages offering potential bundle savings. They cover England and Wales.

GreenMatch is not an installer – it is a comparison platform that connects homeowners with up to 4 pre-vetted local installers. If you want to compare multiple quotes from MCS-certified companies quickly, without approaching each one individually, GreenMatch is a useful tool.

The platform covers the whole of the UK, matches you with local installers based on your property details, and the service is free to use. The quality of the installers in their network varies by region, so always cross-reference any installer you receive against their Trustpilot score and MCS certification before proceeding. GreenMatch is best used as a quote-gathering starting point rather than an end-to-end solution.

How to Choose a Solar Panel Installer

Before approaching any installer, work out the system size you need for your home. Then the five non-negotiable checks before signing any solar installation contract are: MCS certification, Trustpilot score (minimum 4.3/5 with 100+ reviews), a written quote specifying panel make and model, a maximum 25% deposit, and a clear workmanship warranty of at least 5 years.

1. Verify MCS Certification First

MCS (Microgeneration Certification Scheme) certification is not optional – it is a legal requirement to access the Smart Export Guarantee and to apply for the Warm Homes: Local Grant. An MCS-certified installation also provides a Certificate of Compliance which you will need for building regulations and insurance purposes. Check any installer at mcscertified.com before agreeing to a quote. Do not rely on the installer's own word; verify directly on the MCS register.

2. Get a Minimum of 3 Quotes

Prices for the same 4kW system from the same panel brand can vary by up to 40% between different MCS-certified installers. Always obtain at least 3 written quotes that specify the panel make, model, output, inverter brand, expected output from your system (kWh annually), and total system cost including VAT. Comparing quotes on price alone is insufficient; compare the specification carefully.

3. Check Reviews on Multiple Platforms

Trustpilot is the most reliable independent review platform for solar installers, but also check Google Reviews and Which? Local. Look specifically at reviews from the past 12 months and read negative reviews carefully to understand how the company handles complaints. A minimum of 4.3/5 from 100+ reviews is a reasonable baseline for a credible installer.

4. Review the Warranty Terms

A professional installation should include:

• Panel performance warranty: 25 years minimum (guarantees at least 80% of rated output)
• Panel product warranty: 10–15 years (covers manufacturing defects)
• Inverter warranty: 5–10 years (most standard inverters; some premium brands offer 12 years)
• Workmanship warranty: 5–10 years (the installer's own guarantee on their installation work)

If an installer cannot provide written warranty terms for all four of these, do not proceed.

Best Solar Panel Installers by Region

Solar panel installer quality and pricing varies significantly by UK region. National brands offer consistency, while strong regional specialists often provide more competitive pricing and faster installation slots.

For city-specific guides including local pricing data and region-specific grants, see our solar installation guides for London, Cardiff, Edinburgh, and Liverpool. For a broader look at whether the investment makes sense, visit our guide on are solar panels worth it and our solar panel grants guide to see what funding is available in your area.

Laura Bennet

Home Energy & Sustainability Editor

Laura leads coverage on home energy, heating, and sustainable living. With over 12 years in the UK energy sector, she writes about boilers, solar panels, insulation, and eco-friendly upgrades that reduce household costs.

Reviewed by

Tom Reynolds

Business Energy Specialist