Solar Loan Calculator
See the monthly payment and total interest for a solar loan.
This calculates loan mechanics only (monthly payment, interest) from an amount, APR, and term. For whether the project pays off, see the Payback Calculator or ROI Calculator.
This tool provides a planning estimate based on the assumptions shown below the results — it is not a quote, and actual costs and savings will vary by installer, local rates, and your specific home. Doesn't include lender fees some solar loans charge upfront — ask for the full cost breakdown before signing.
Enter your loan amount, rate, and term to see the monthly payment.
How this calculator works
Standard amortizing loan formula: monthly payment = P × r(1+r)ⁿ ÷ ((1+r)ⁿ − 1), where P is the loan amount, r is the monthly interest rate (APR ÷ 12), and n is the number of monthly payments. This doesn't include any origination fees some solar loans charge upfront — check whether your specific loan offer includes one, since it changes the effective cost beyond what the APR alone shows.
Source: Standard amortizing loan formula, last updated 2026-07-01.