Solar Loan Partner Programs for Installers: How to Choose and Use Them

Mosaic filed for Chapter 11 in June 2025. One of the largest residential solar lenders in the US went from funding thousands of installs a month to a court-supervised wind-down, and every installer who ran all their volume through it had to rebuild their financing stack mid-year. That event changed how smart installers think about solar loan partner programs. The question is no longer “which lender gives me the lowest dealer fee.” It is “which combination of lenders keeps my close rate high and my receivables safe if one of them fails.”

Loans still matter. Third-party ownership now takes over 50% of residential sales, but the other half of the market — ownership-minded buyers — still closes on loan products. The installer who presents financing well wins that half. The one who treats the lender as a black box loses margin to dealer fees, loses deals to credit declines, and loses sleep to slow funding.

This guide is the installer-side playbook we use when structuring financing partnerships. It covers how loan partner programs actually work, what the 2026 lender market looks like after Mosaic, dealer fee math with real numbers, program tiers, approval and funding benchmarks, and how to wire a lender into your sales workflow without giving up control of the customer. For the homeowner-side overview of every financing structure, see our solar financing options guide. For the broader cash-versus-lease-versus-PPA presentation playbook, see the solar financing guide for installers.

In this guide:

• What a solar loan partner program actually includes — and what it costs you
• The 2026 lender market after the Mosaic bankruptcy
• Dealer fee math: how 10–30% fees move your margin
• A comparison table of the major programs: GoodLeap, Sunlight, Sungage, LightStream, credit unions
• Approval rates and funding speed — the 2 metrics that decide close rate
• Program tiers and volume commitments: when concentrating pays
• The contrarian case for offering no in-house loan at all
• How to integrate a loan partner into your sales workflow

What a Solar Loan Partner Program Actually Is

A solar loan partner program is a business-to-business arrangement between a lender and an installer. The lender provides a point-of-sale platform. Your sales rep enters the customer’s details during the site visit or video call. The platform returns a credit decision in under 60 seconds in most cases. If approved, the customer e-signs loan documents, and the lender funds you at agreed milestones — typically install completion and permission to operate (PTO).

The program includes 4 components you should evaluate separately.

First, the credit product itself. This is the loan the homeowner signs: term length (10–25 years), APR, promotional structure, and prepayment terms. Mosaic pioneered 20- and 25-year solar loans and products with no payments for 18 months, according to the Bondoro Mosaic case summary (2025).

Second, the dealer fee. This is what the lender charges you for originating the loan, deducted from the funded amount. We cover the math in detail below.

Third, the funding waterfall. This defines when money hits your account: milestones, holdbacks, and document requirements.

Fourth, the installer portal and support layer. This includes the sales app, co-branded materials, training, and the escalation channel when a deal gets stuck in underwriting.

Notice what the program does not include: the customer relationship. The lender owns the loan and services it for 10–25 years. Your brand sits on the install. Their brand sits on the payment. When the loan experience goes badly — confusing statements, escrow-style true-ups, transfer problems at home sale — the homeowner remembers the installer who set it up. Choose partners whose servicing reputation you can defend at the kitchen table.

The 2026 Lender Market: Who Is Left and Who Is Stable

Lender stability is now a first-order selection criterion. It was not in 2021. Three forces reshaped the market in 24 months.

Interest rates compressed lending margins. Consumer solar loans depend on the spread between the lender’s cost of capital and the borrower APR. Warehouse facility costs rose sharply from 2022 onward, and thin-margin lenders could not reprice fast enough, according to the Bondoro Mosaic case summary (2025).

The federal residential tax credit expired on December 31, 2025. That removed the 30% credit that many loan products assumed in their payment structure. The US market still installed 11.7 GWdc in Q3 2025 — a 20% increase over Q3 2024 — but the distributed segment faced rush-to-beat-the-deadline distortions, according to the SEIA Solar Market Insight Q4 2025 report.

Dealer-fee litigation and regulation raised compliance costs. The Consumer Financial Protection Bureau called out hidden markups in its August 2024 Issue Spotlight on solar financing, and state bills followed. California’s SB 784, for example, proposed documentation requirements for dealer fees on residential solar loans.

The result, as of mid-2026:

GoodLeap remains the scaled player. It operates an asset-light model — originating loans and pre-selling them to institutional investors through forward purchase agreements — and completed $909M of home improvement loan securitizations in 2025, according to Sacra’s GoodLeap company research (2026). That securitization cadence is a useful health signal: a lender that keeps selling loan pools to institutional buyers has functioning capital markets access.

Dealer Fees: The Number That Decides Your Margin

The dealer fee is the single largest variable in loan-partner economics. It is also the most misunderstood.

A dealer fee is the discount a lender takes when buying the loan from you. You quote a $30,000 cash price. The lender’s product has a 25% dealer fee. The customer signs a $40,000 loan. The lender keeps the $10,000 difference and remits $30,000 to you. The customer pays interest on the full $40,000.

The CFPB measured this practice directly. Hidden fees “typically range from between 10 to 30 percent of the cash price but can exceed 50 percent,” according to the CFPB Issue Spotlight on solar financing (2024).

Here is what that does to a real job. Hypothetical example, but representative of quoted 2026 terms:

Your margin stays flat in this structure. The fee lands entirely on the customer. That is why the CFPB cares, and why your reputation is on the line even though your P&L looks unchanged.

The margin hit comes when you compete on monthly payment. Reps commonly absorb part of the fee to keep the financed payment under the utility bill. Drop the loan price to $37,000 in the example above and your remittance falls to $27,750 — a $2,250 margin cut on a single job. Across 120 financed jobs a year, undisciplined fee absorption costs $270,000.

The practical rules we follow:

1. Get the full fee schedule, not the headline product. Lenders quote the low-fee flagship (often 8–14%) and bury the low-APR promotional products (25–40%) that reps actually use to close.
2. Price the fee into the financed quote, always. Show the customer the cash price and the loan price as separate line items. Transparency is also your legal defense as fee-disclosure rules tighten.
3. Cap rep discretion on fee absorption. Set a maximum margin discount per deal (we use $1,000) above which the sales manager must approve.

Model the payment and savings side by side before the rep ever quotes. The generation and financial tool in SurgePV runs payback and cash-flow in the same workspace as the design, so the financed payment gets compared against real production numbers — not a spreadsheet built the night before.

Comparing the Major Solar Loan Partner Programs

No public source maintains current dealer-fee schedules — lenders treat them as negotiated terms. The table below reflects the fee and product ranges we have observed in installer agreements and industry reporting through mid-2026. Treat every number as a starting point for negotiation, not a quote.

Three patterns stand out.

Fee and APR trade inversely. A 0% dealer fee loan carries a market-rate APR (LightStream ranges roughly 4.49–9.99% depending on credit, per its product page). A 3.99% promotional APR carries a 25–35% fee. There is no cheap loan. There is only a choice of who pays — customer through interest, or you through the fee.

The zero-fee options serve a different customer. LightStream-style unsecured loans work for excellent-credit buyers who want speed and no lien complexity. They do not work for a 660-FICO buyer stretching to afford the system. You need both in the stack.

Credit unions are the underused channel. A regional credit union home-improvement loan often beats platform fees by 10+ points. The tradeoff is workflow: no solar-specific portal, slower document handling, and no sales app. For 5–10 jobs a month, the margin recovered justifies the friction. Above that volume, the operational cost catches up.

Approval Rates and Funding Speed: The 2 Metrics That Decide Close Rate

Dealer fees get the attention. Approval rate and funding speed do the damage.

Approval rate

Every credit decline is a dead deal after the customer already said yes. Across a full applicant pool, solar loan approval rates typically run 60–80% in our experience, varying with the lender’s credit box and your lead quality. Two installers with identical lead flow can see 15-point approval-rate gaps on the same lender, because application completeness and debt-to-income presentation differ.

Ask each prospective partner for 2 numbers before signing: their overall approval rate, and their approval rate on scores between 640 and 700. The second number is where volume lives. A lender with a 75% headline rate that declines half your sub-700 applicants gives you worse economics than a 68% lender that works the marginal files.

Also ask what happens to declines. Some platforms automatically waterfall a declined application to a second product or partner lender. That recovers 5–15% of otherwise-lost deals — meaningful at 20 applications a month.

Funding speed

Slow funding is a cash-flow tax. Most programs pay in 2 stages: 60–80% at install completion, the balance at PTO. PTO timing sits outside your control — the utility drives it — and can take 2–8 weeks in slow jurisdictions.

Run the receivables math for your volume. Hypothetical example: 10 financed jobs a month at a $32,000 average remittance, 30% held until PTO, 4-week average PTO lag. That is roughly $96,000 permanently trapped in the funding pipeline. If your lender slips its install-milestone payment from 5 days to 15 days, add another $50,000 of working capital need. We cover the broader discipline in our installer cash flow management guide.

What to negotiate:

• 100% funding at install completion, with the lender taking PTO risk. Several programs now offer this at a slightly higher fee. For most installers, the fee premium costs less than the working capital.
• A written funding SLA — days from document completion to ACH — with escalation contacts.
• Document checklist automation. Most funding delays trace to missing lien releases, permit sign-offs, or photos, not the lender’s treasury.

Program Tiers and Volume Commitments

Every major loan partner runs a tiered program. Concentrate volume, earn better terms. Typical structures we have seen:

The tier game has a real payoff. A 2-point fee discount on $300,000 of monthly funded volume returns $6,000 a month. That is a full-time coordinator’s salary.

It also has a trap. Tier economics push you toward a single lender, and single-lender dependence is exactly what hurt installers in 2025. Mosaic’s filing left concentrated partners re-papering active deals and re-quoting customers mid-pipeline. The installers who absorbed the shock in weeks were running 2 or more lending partners.

Our position: run 2 active loan partners, and deliberately split volume 70/30. The primary partner earns near-tier-max economics. The secondary partner stays warm — your reps know its portal, your pipeline has live files in it, and switching cost is near zero if the primary fails or reprices. The 30% costs you some tier discount. Price that as insurance, because it is.

Revisit the split twice a year. Lender terms, credit boxes, and stability all move faster than annual reviews catch.

The Contrarian Case: Sometimes the Best Loan Partner Is No Loan Partner

The default industry advice is “always offer financing at the point of sale.” We disagree — with a condition.

The myth: in-house financing always raises close rates. The reality: it raises close rates on financed buyers, and it quietly taxes everyone. The dealer-fee inflation dynamic pushes quoted system prices up across the market. When your competitor quotes $40,000 financed against your $31,000 cash price, you win the informed buyer. The CFPB’s disclosure push, and state bills like California’s SB 784, keep widening the pool of informed buyers.

We have watched installers in cash-heavy markets — parts of Texas, Florida, and the Mountain West — run 70%+ cash close rates with no lender portal at all. Their pitch is simple: here is the cash price, here is what a loan adds to it, here is a credit union we like. The transparency itself closes.

The exception matters, though. Post-ITC, cash economics weakened: a typical 6–8 kW system at $19,000–$29,000 now shows 9–13 year simple payback in many markets, and third-party ownership captured over 50% of H1 2025 residential sales because leased systems still access commercial tax credits. Refusing to offer any financing in that environment forfeits the ownership-minded-but-capital-constrained segment — often 30–50% of a residential pipeline.

The honest answer is a spectrum. Minimum viable financing: a clean cash price plus one referral relationship (credit union or LightStream-style product). Full stack: 2 loan partners, a TPO option, and cash. Choose based on your market’s cash-buyer share, not on industry habit.

How to Integrate a Loan Partner into Your Sales Workflow

The partner you pick matters less than how you wire it in. A lender portal that lives outside your sales process gets used badly — reps quote from memory, fees get absorbed silently, and finance deals close on stale payment numbers.

The workflow that works, step by step:

1. Design and financials first, financing second. Build the system design and run production numbers before any loan conversation. Payment talk without yield data produces deals that underperform the pitch. A cloud solar software platform that ties design to financial output keeps this sequence honest.
2. Present 3 options on one page. Cash, loan, and lease/PPA side by side, each with monthly payment, 25-year total cost, and lifetime savings. Our solar proposal software generates this comparison directly from the design, so the financed numbers inherit real production data instead of rep estimates. Good proposal examples all share this structure.
3. Run credit only after the customer picks a direction. A credit pull is a commitment signal and a compliance event. Do not spend it on shoppers.
4. Standardize the fee math. Build the dealer fee into your quoting template per product, so every rep quotes the same financed price for the same job. Audit monthly against funded deals.
5. Track the financing funnel like your sales funnel. Applications, approvals, declines, cancels, days-to-funding — per lender, per rep. Financing metrics belong in the same review as your close rate numbers.
6. Script the disclosure. The rep states, in plain language: “The cash price is X. The loan amount is Y, which includes the lender’s origination fee. Your APR is Z.” Record it in the proposal. This is where the market is heading legally, and early adopters look better by comparison.

Model every option before the kitchen-table meeting. Our solar loan calculator sanity-checks payments, and the loan, cash, and PPA modeling glossary entry covers how each structure flows through a 25-year projection.

Conclusion

Solar loan partner programs are a margin decision, a cash-flow decision, and — after 2025 — a counterparty-risk decision. The installers who treat lender selection as procurement, with fee schedules, SLAs, and stability checks, keep their close rates and their receivables. The ones who sign the first portal they are offered donate 2–5 points of margin and inherit someone else’s balance-sheet risk.

Do 3 things this quarter:

• Pull your actual numbers. Approval rate, average dealer fee across funded deals (not the rate card), and days-to-funding per lender. Most installers have never computed the blended fee they really pay.
• Add or refresh a second lending partner. Split volume 70/30, keep both portals live, and put a calendar reminder to re-bid terms every 6 months.
• Rebuild the proposal around comparison. Cash, loan, and TPO on one page, with the dealer fee visible. It closes better, and it is where disclosure rules are going anyway.

Frequently Asked Questions

What is a solar loan partner program?

A solar loan partner program is a lender’s point-of-sale financing platform built for installers. It lets your sales team run credit, structure loans, and get funded through one lender portal. Examples include GoodLeap, Sunlight Financial, and Sungage Financial, plus bank products like LightStream. The installer pays a dealer fee, typically 10–30% of the cash price, in exchange for instant approval and fast funding.

How much are dealer fees on solar loans?

Dealer fees on solar loans typically range from 10% to 30% of the cash price, and can exceed 50% on low-APR promotional products, according to the Consumer Financial Protection Bureau (2024). A $30,000 cash job with a 25% dealer fee becomes a $40,000 loan principal. The fee comes out of the installer’s margin unless it is priced into the financed quote.

What happened to Mosaic solar loans?

Mosaic filed for Chapter 11 bankruptcy in June 2025 after rising capital costs and policy uncertainty squeezed its lending margins. The case shows why installers should never depend on a single loan partner. Installers who ran 2 or more lending partners absorbed the disruption within weeks. Single-partner shops scrambled to re-paper active deals.

What credit score do homeowners need for a solar loan?

Most solar loan partners approve borrowers with FICO scores of 640–650 and above, with the best rates reserved for scores over 700. Approval rates across a full applicant pool typically run 60–80%, depending on the lender and product. Check each partner’s published minimums and ask for your own historical approval data before signing.

How fast do solar lenders pay installers?

Funding speed varies by lender and milestone. Most solar loan partners pay in 2 stages: a partial payment at install completion and the balance at permission to operate (PTO). Typical timelines run 5–30 days per milestone. Some lenders now fund 100% at install completion. Slow PTO-based funding can trap $200,000 or more in receivables for an installer doing 10 jobs a month.

Should installers offer loans, leases, or cash in 2026?

Offer all 3. Cash buyers get the strongest economics. Loans serve homeowners who want ownership without upfront cost. Leases and PPAs now capture over 50% of residential sales because third-party systems still claim commercial tax credits. Present all options side by side in the proposal and let the customer’s finances drive the choice.

How many solar loan partners should an installer have?

Run at least 2 active lending partners plus a cash price at all times. Multiple partners protect you when a lender tightens credit, raises fees, or exits the market — as Mosaic did in 2025. The tradeoff is volume: lender tiers reward concentration, so a 3-partner shop earns worse terms than a focused one. For most residential installers, 2 partners balance resilience and pricing.