What is a solar dealer fee?

A payment the installer makes to the lender so it can offer you financing or a particular rate. It is generally added to the loan principal, so it is not a line item and not in the stated APR. The CFPB describes fees that raise loan cost 30% or more above the cash price.

Is the stated APR on my loan wrong?

Probably not. The Truth in Lending Act computes APR on the amount financed, and a dealer fee inside that amount is generally principal, not a finance charge. The stated rate can be accurate and still not tell you what the system costs. This tool measures that gap; it is not an allegation about your lender.

How do I find out my dealer fee if nobody will tell me?

Ask the installer in writing for the cash price of the identical system: same panels, inverter and scope, no financing. The difference from your amount financed is the fee. If the two match, there is no fee. If they decline to give a cash price, that tells you something about the quote.

Why does a shorter loan show a higher effective rate?

The dealer fee is a fixed number of dollars recovered across the payments. Over 300 payments it is 5.79% with the example inputs; over 144 it is 8.37%. The shorter loan still costs less in dollars, $18,095 above cash against $27,514, but as a rate it is worse.

Why is your default fee 25%?

It is a round placeholder for a range we can describe but cannot measure. The CFPB documents fees raising loan cost 30% or more above cash price but publishes no distribution to average, and we will not invent one. Replace 25% with your real figure.

How does this differ from your loan calculator?

The loan calculator starts from a cash price and gives the payment and total cost once a fee and rate apply. This tool starts from the loan document and solves for the rate against the cash price. Use that one when planning, this one with a contract in hand.

Should I take the cash price and borrow elsewhere?

Run the comparison. If the effective rate here is 5.79% and a credit union would lend the cash price at 7%, the dealer financing is cheaper. At 6%, it is not. You cannot compare at all without a cash price, which is the practical reason to insist on one.

What is the 18-month reamortization my contract mentions?

Some solar loans assume a large voluntary principal payment around month 18, sized to a 30% federal credit, and price the payment as if you make it. Skip it and the loan re-amortizes and the payment rises. For systems placed in service after 2025 the §25D credit is $0. This tool models a flat payment.

Does a dealer fee mean I was defrauded?

No. Dealer fees are a generally lawful feature of point-of-sale financing, in solar and elsewhere. What varies by state is whether the cash price must be disclosed to you. The useful question is not whether a fee exists but whether you were given enough information to compare the deal against alternatives.

Can I use this for a HELOC or a home equity loan?

You can, and the answer will be that the effective rate equals the stated rate, because those products do not carry a capitalized dealer fee. That is the point of running the comparison: it shows you what a loan without an embedded fee looks like.

HyreSolar tools

The real rate on your solar loan

Solves the APR you pay against the cash price once a dealer fee sits inside the amount financed. Enter the numbers from the loan document.

Checked September 3, 2026. Data as of September 5, 2026. HyreSolar sells and installs nothing.

This solar dealer fee calculator gives an estimate from your own numbers in under a minute, with every assumption listed under the result.

A dealer fee raises the rate you pay on the cash price, even when the APR on the contract is correct. A $41,000 loan at 2.99% over 25 years with a 25% dealer fee is an effective 5.79% APR against the $30,750 cash price, 2.80 points above the contract rate. The fee is $10,250.

A dealer fee is the charge a lender takes for offering a low advertised rate through an installer. The installer pays it, then adds it to the price you finance.

The CFPB’s 2024 report on solar financing found these fees are usually capitalized into the loan principal and excluded from the APR, so a contract can show a correct, legally compliant APR and still cost you far more than that rate implies against the cash price.

This calculator works backwards from the loan document. Enter the amount financed, the stated APR, the term and the fee, and it solves for the rate you are effectively paying on the cash price.

The gap between the two rates is the cost of the fee spread over the loan.

If you do not know the fee, ask for it in writing, or ask for the cash price and compare: the difference between the amount financed and the cash price is the fee.

A dealer fee is not fraud and is lawful in most places. What matters is whether you can compare the offer with alternatives, such as a home equity line, a credit union loan or paying cash, none of which carry a capitalized fee.

Run each through the loan calculator at its own rate and see which total is lower. If you want quotes that state the cash price up front, the form under the result sends your figures to installers on that basis.

Find your effective APR

Enter what the loan document says; the tool solves for the rate against the cash price. Nothing is stored or emailed.

Example values The filled-in numbers are an example, not your home. Type over them with your own.

— Effective APR

— Above the stated APR

— Implied cash price

— Dealer fee in dollars

— Monthly payment

— Paid above cash price

How this result was worked out

Working it out from the numbers above.

Effective APR solved against the implied cash price. Not a finance offer and not legal advice.

A cash price in writing from your installer beats every default here. HyreSolar does not sell systems and does not broker loans.

How to read the two rates

Both numbers are true, and they are not measuring the same thing. The stated APR is computed under the Truth in Lending Act on the amount financed.

The effective APR here is computed on the cash price: what the same system costs without the financing program attached. When those two figures differ, the gap is the dealer fee expressed as a rate.

A low headline rate can be bought, not given. Run the calculator at 0.99% and the effective rate is 3.52%; run it at 6.99% and it is 10.46%.

The installer pays the lender for the right to advertise a low rate, and that payment goes into your principal. Ask whether a low advertised rate comes with a dealer fee.

The question this answers is not "is my loan bad". It is "what would this system cost me in cash, and am I being shown that number". A homeowner who knows the cash price can compare it against other quotes on a like-for-like basis. A homeowner who only knows the financed price cannot.

Gap under 1 point: Either the fee is small or you have entered a fee that was disclosed to you rather than one you inferred. Ask for the cash price in writing to confirm.
Gap of 1 to 3 points: What a mid-sized dealer fee in the principal produces in this model. Worth knowing before you sign, and worth asking whether a cash-price purchase plus your own financing is cheaper.
Gap above 3 points: The financing is a substantial part of what you are buying. Compare the cash price against a home equity product or a credit union solar loan before proceeding.

Where to find each number

Where each input comes from, so nothing is a guess.

1. Enter the amount financed

The loan principal, not the system price and not the total of payments. This is the figure the lender is lending you.

Where to find it: Your Truth in Lending disclosure, on the line labeled "Amount Financed". It is a required TILA box and it will be on the same page as the APR.

2. Enter the stated APR

The annual percentage rate printed on the loan document. Use the number as given; the tool does not second-guess it.

Where to find it: The TILA disclosure box, labeled "Annual Percentage Rate". If your paperwork shows an interest rate and an APR that differ, use the APR.

3. Enter the term in years

How long the loan runs, from 10 to 25 years on the loans we have read. The term moves the effective rate more than it looks, as the scenario table shows.

Where to find it: The loan agreement, where it may be written as a number of monthly payments. Divide by 12 if it is given in months.

4. Enter the dealer fee, if you know it

As a percentage of the amount financed. If it was disclosed, use the disclosed figure. If it was not, this is the input you are testing.

Where to find it: Ask the installer directly, in writing, for the cash price of the same system. The difference between that and the amount financed is the fee. If they will not give you a cash price, that itself is information.

5. If you have the cash price, work backwards

You do not need the installer to name a fee percentage. Divide the cash price by the amount financed, subtract from one, and multiply by 100.

Where to find it: A $30,750 cash price on a $41,000 loan is 1 − (30,750 ÷ 41,000) = 25.0%. Enter 25.

6. Read the gap, not just the rate

The output to watch is the spread between the stated APR and the effective one. That spread is the price of the financing, stated as a rate.

Where to find it: Compare it against what a credit union or home equity line would charge you on the cash price. That is the only fair comparison available.

How the calculator works it out

1
Compute the payment
Standard amortization on the amount financed at the stated APR. This is the payment your contract commits you to.
2
Infer the cash price
Amount financed × (1 − dealer fee). This is what the tool believes the system costs without the financing program.
3
Solve for the rate
Bisection for the monthly rate at which the cash price equals the present value of that same payment stream. 200 iterations, so the answer is exact to well past the printed precision.
4
Report both, and the gap
Stated APR, effective APR, and the spread in percentage points. The engine does not judge which is fair.

The formula, in full. payment = P × r ÷ (1 − (1+r)^−n), where P is the amount financed, r the stated APR ÷ 12, n the term in months. cash = P × (1 − fee).

Effective APR is the i solving cash = payment × (1 − (1+i)^−n) ÷ i, reported as i × 12.

A worked example, start to finish

A 12 kW system sold on a 25-year loan at an advertised 2.99%, with a dealer fee at the midpoint of the range this tool models. The homeowner was shown a monthly payment and a rate. They were never shown a cash price.

Step	Value
Amount financed	$41,000
Stated APR	2.99%
Term	25 years, 300 payments
Dealer fee entered	25% of the amount financed
Implied cash price	$30,750
Dealer fee in dollars	$10,250
Monthly payment	$194
Result	5.79% effective APR

The contract says 2.99% and the contract is not lying. But $194 a month for 300 months against a system worth $30,750 in cash is a 5.79% loan.

The homeowner pays $27,514 above the cash price across the term. Had they been quoted the cash price and borrowed $30,750 at 2.99% with no fee, the payment would be $146, not $194.

How the answer moves

The same $41,000 / 2.99% / 25-year loan, one input changed at a time. Every figure is computed by the calculator on this page.

Change	Implied cash price	Fee	Payment	Effective APR	Gap
Base case$41,000, 2.99%, 25 yr, 25% fee	$30,750	$10,250	$194/mo	5.79%	+2.80 pts
Fee 0%: a true cash-price loan	$41,000	$0	$194/mo	2.99%	+0.00 pts
Fee 10%	$36,900	$4,100	$194/mo	3.97%	+0.98 pts
Fee 15%	$34,850	$6,150	$194/mo	4.53%	+1.54 pts
Fee 20%	$32,800	$8,200	$194/mo	5.13%	+2.14 pts
Fee 30%	$28,700	$12,300	$194/mo	6.52%	+3.53 pts
Headline 0.99% instead of 2.99%	$30,750	$10,250	$154/mo	3.52%	+2.53 pts
Headline 6.99% instead of 2.99%	$30,750	$10,250	$290/mo	10.46%	+3.47 pts
Term 12 years not 25	$30,750	$10,250	$339/mo	8.37%	+5.38 pts
Term 20 years not 25	$30,750	$10,250	$227/mo	6.38%	+3.39 pts

Read the last two rows carefully. A shorter term makes the same dealer fee bite harder as a rate, because the same dollars are recovered over fewer payments: 25% at 12 years is 8.37%, the same 25% at 25 years is 5.79%.

A shorter loan is cheaper in total interest and more expensive in effective rate.

What moves this number most

Ranked, largest first. A proposal can change any of these without saying anything untrue, so check these inputs first.

1. The dealer fee itself

The reason the tool exists, and the input you may not have been given. Moving from 0% to 30% takes a 2.99% loan to 6.52% without changing a single number on the contract.

2. The term

Counter-intuitively powerful. The fee is a fixed dollar amount recovered across the payment stream, so a shorter stream concentrates it. The same 25% fee is 8.37% effective at 12 years and 5.79% at 25.

3. The stated APR

Moves the effective rate roughly in step, but not proportionally: the fee adds its own spread on top. A 0.99% headline is 3.52% effective; a 6.99% headline is 10.46%. The absolute gap grows with the rate.

4. Whether a cash price exists at all

Some installers price the same system identically for cash and finance. If that is true of yours, the fee is zero and the stated APR is the real one. The way to find out is to ask for the cash price in writing.

5. What is deliberately absent

Origination charges outside the dealer fee, prepayment behavior, the 18-month reamortization some solar loans assume, and any tax credit. Each is real and each is outside a rate comparison. The reamortization matters more now that §25D has ended; see the FAQ.

Common mistakes with this calculation

Comparing a financed price to another financed price
Two quotes each carrying an undisclosed and different dealer fee are not comparable, however carefully you line up the monthly payments. Get both cash prices, or you are comparing financing products while believing you are comparing solar systems.
Treating the stated APR as wrong or illegal
It is generally neither. TILA computes the rate on the amount financed, and a capitalized dealer fee is inside that amount rather than treated as a finance charge. The disclosure can be fully compliant and still leave you without the number you need.
Entering the total of payments as the amount financed
They are different TILA boxes and the gap between them is the interest. Using the total of payments will produce a nonsense cash price and a meaningless rate.
Assuming a shorter term costs less in every way
In total dollars it does. As an effective rate against a dealer fee, it costs more, because the fee is amortized over fewer payments. Both facts are true at once and the scenario table shows them side by side.
Guessing a fee and then treating the output as measured
If you entered an assumed 25% because you were not told, the effective APR is a hypothesis, not a finding. It is still useful: it tells you how much the answer depends on a number nobody would give you.
Assuming the 30% credit will pay down the balance
Some solar loans are structured around a voluntary principal reduction in month 18, sized to a 30% federal credit. For systems placed in service after 31 December 2025 that credit is $0 under §25D. If the paydown does not happen, the payment re-amortizes upward.

Embed this calculator

Free to use on any site, including news and installer pages. Paste this where you want the calculator to appear. Keep the credit line: it is the only condition.

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<p><a href="https://hyresolar.com/tools/dealer-fee-calculator/">Solar dealer fee calculator</a> by HyreSolar</p>

What this calculator leaves out

The result is a planning estimate. A real proposal accounts for these; this page does not.

The dealer fee is an input, not a measurement.
If it was not disclosed to you, the output is a hypothesis about a number you were not given.
Origination, documentation and prepayment charges outside the capitalized dealer fee are not modeled.
The 18-month reamortization found in some solar loans is not modeled.
If your loan has one, the real payment path is not flat.
No tax credit is applied.
§25D is $0 for systems placed in service after 31 December 2025.
This is an arithmetic comparison, not legal advice and not a finance offer.
Whether a specific disclosure complied with TILA is a question for a lawyer or your state regulator.

The research behind these numbers

Solar loan calculatorThe companion tool. That one answers what the payment is; this one answers what rate you are paying for the system.Read the research Proposal analyzerNormalizes a quote to $/W and unwinds a dealer fee, so you can compare two bids for differently sized systems.Read the research What zero-down solar costsWhere the money comes from when no money changes hands at signing.Read the research What the §25D expiry changedWhy a loan structured around a 30% credit paydown may no longer behave as sold.Read the research Door-to-door solar salesThe in-home sales channel and the rules that apply to it.Read the research The UCC-1 on your propertyWhat the lender files against the house, and what it does when you sell.Read the research Selling a house with a solar loanThe point at which the difference between cash price and financed price becomes somebody else’s problem.Read the research Solar sales regulation by stateWhich states require a cash price to be disclosed, and which do not.Read the research

Questions this calculator answers

What is a solar dealer fee?: A payment the installer makes to the lender so it can offer you financing or a particular rate. It is generally added to the loan principal, so it is not a line item and not in the stated APR. The CFPB describes fees that raise loan cost 30% or more above the cash price.
Is the stated APR on my loan wrong?: Probably not. The Truth in Lending Act computes APR on the amount financed, and a dealer fee inside that amount is generally principal, not a finance charge. The stated rate can be accurate and still not tell you what the system costs. This tool measures that gap; it is not an allegation about your lender.
How do I find out my dealer fee if nobody will tell me?: Ask the installer in writing for the cash price of the identical system: same panels, inverter and scope, no financing. The difference from your amount financed is the fee. If the two match, there is no fee. If they decline to give a cash price, that tells you something about the quote.
Why does a shorter loan show a higher effective rate?: The dealer fee is a fixed number of dollars recovered across the payments. Over 300 payments it is 5.79% with the example inputs; over 144 it is 8.37%. The shorter loan still costs less in dollars, $18,095 above cash against $27,514, but as a rate it is worse.
Why is your default fee 25%?: It is a round placeholder for a range we can describe but cannot measure. The CFPB documents fees raising loan cost 30% or more above cash price but publishes no distribution to average, and we will not invent one. Replace 25% with your real figure.
How does this differ from your loan calculator?: The loan calculator starts from a cash price and gives the payment and total cost once a fee and rate apply. This tool starts from the loan document and solves for the rate against the cash price. Use that one when planning, this one with a contract in hand.
Should I take the cash price and borrow elsewhere?: Run the comparison. If the effective rate here is 5.79% and a credit union would lend the cash price at 7%, the dealer financing is cheaper. At 6%, it is not. You cannot compare at all without a cash price, which is the practical reason to insist on one.
What is the 18-month reamortization my contract mentions?: Some solar loans assume a large voluntary principal payment around month 18, sized to a 30% federal credit, and price the payment as if you make it. Skip it and the loan re-amortizes and the payment rises. For systems placed in service after 2025 the §25D credit is $0. This tool models a flat payment.
Does a dealer fee mean I was defrauded?: No. Dealer fees are a generally lawful feature of point-of-sale financing, in solar and elsewhere. What varies by state is whether the cash price must be disclosed to you. The useful question is not whether a fee exists but whether you were given enough information to compare the deal against alternatives.
Can I use this for a HELOC or a home equity loan?: You can, and the answer will be that the effective rate equals the stated rate, because those products do not carry a capitalized dealer fee. That is the point of running the comparison: it shows you what a loan without an embedded fee looks like.

Sources and methodology

Figures dated September 5, 2026. Last reviewed September 3, 2026 by the HyreSolar research desk, which writes and checks every tool on this site.

Issue Spotlight: Solar Financing (Consumer Financial Protection Bureau, retrieved September 5, 2026). Published 7 August 2024. Source for dealer fees being capitalized into principal, excluded from the stated APR, and raising loan cost by 30% or more above the cash price.
Regulation Z, 12 CFR §1026.22: determination of annual percentage rate (Consumer Financial Protection Bureau / eCFR, retrieved September 5, 2026). The rule under which the stated APR is computed on the amount financed. Basis for the statement that a compliant APR can still exclude the fee.
Regulation Z, 12 CFR §1026.4: finance charge (Consumer Financial Protection Bureau / eCFR, retrieved September 5, 2026). Defines which charges are finance charges and which are not, the distinction that keeps a capitalized dealer fee outside the disclosed rate.
Residential Clean Energy Credit (§25D) (Internal Revenue Service, retrieved September 5, 2026). Basis for the statement that the credit is unavailable for property placed in service after 31 December 2025, which breaks the reamortization assumption in some solar loans.
U.S. Solar Photovoltaic System Cost Benchmark (NREL, retrieved September 5, 2026). Context for whether an implied cash price is plausible for the system size. Replace with a real cash quote before relying on it.

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