Where our information comes from
Our guides are compiled from primary sources: state program administrators (Illinois Shines, the CPUC, Hawaii's Department of Taxation), utility tariff pages and program documentation (Hawaiian Electric, PG&E, SCE, SDG&E, ComEd, Ameren, and municipal utilities), the IRS, and federal energy statistics from the U.S. Energy Information Administration. Every state guide ends with a source list including the date we last checked each source.
How estimates are built
City and state savings figures are calculated from public residential electricity rates and typical household usage, combined with regional sun-hour data. They are directional estimates meant to help you compare markets — not quotes. Your actual costs and savings depend on system size, roof characteristics, equipment, installation requirements, financing, your utility's current programs, and installer pricing. Every estimate on this site is labeled as such.
Review cadence
Solar policy changes on program timelines, not news cycles. Each guide carries a "last reviewed" date, and we prioritize re-review when programs are known to change — block pricing steps in Illinois, export-rate updates in California, and battery program revisions in Hawaii. If a program's status is uncertain, we say so and link to the official source rather than guessing.
Installer comparison evidence threshold
Installer pages separate five evidence areas: (1) a sourced relationship to the city, labeled as a physical local office, nearby regional office, or service-area coverage; (2) current state license or program standing; (3) a written workmanship-warranty statement; (4) equipment or service categories disclosed by the company; and (5) a dated observation from a public review source. Each claim links to its source and shows when it was checked.
We publish an editorial score only when all five evidence areas are present, the workmanship term clearly applies to installer labor, and the review observation includes a comparable numeric rating observed within the previous 24 months. That threshold is a publication gate, not a guarantee of quality. When an area is missing, ambiguous, or stale, the page says “not verified” or withholds the score instead of filling the gap with an assumption. Review-site ratings are point-in-time observations owned by their publishers, not ratings created by Switch to Solar.
For records that clear the gate, the 100-point score is computed from current license or program standing (25 points), the published workmanship term (up to 20), the city relationship (up to 15, with a physical local office receiving more weight than service coverage), disclosed equipment (15), and the observed numeric review rating (up to 25). We do not convert BBB letter grades or review counts without a numeric rating into review points.
Company inclusion is editorial. It does not mean the company buys leads from us or participates in our referral marketplace. Conversely, a company reached through a quote-request form may not appear in the editorial comparison. Referral compensation never increases an editorial score or changes a sourced field.
What we will not publish
- Fabricated testimonials, reviews, star ratings, or "as seen in" logos.
- Invented install counts, customer counts, or awards.
- Specific installer pricing presented as fact, or "guaranteed savings" claims.
- Countdown-timer urgency around incentives that have no actual deadline.
How referrals relate to content
We may be compensated when you request quotes through our forms. Editorial content is produced independently of that compensation: program descriptions, cost ranges, and cautions (including warnings about sales tactics) are written from the sources, not from partner relationships. Being mentioned on this website does not automatically mean a company or program is the best option for every homeowner. Full details are in our Affiliate & Compensation Disclosure.
Corrections
If you find an error or an out-of-date program detail, contact us. We correct verified errors and update the page's review date.