The dealer fee
The largest hidden variable. Moving from no fee to 20% adds $11,864 over the term at the same interest rate. Moving to 30% adds $20,338. None of this appears in the advertised APR.
HyreSolar tools
Solar Loan Calculator
The payment is not the price. This shows what the dealer fee does to both.
Solar loans are frequently sold on a monthly payment while a dealer fee is added to the amount financed. This model puts the fee where it belongs, inside the principal, and shows the payment, the total paid and how much more than cash you end up paying.
What this returns at the defaults
A $30,000 system financed over 25 years at 3.99% with a 20% dealer fee means you are borrowing $37,500, not $30,000. The payment is $198 a month and you repay $59,320. The same system with no dealer fee at the same headline rate is $158 a month and $47,456 total. The fee costs $11,864 over the term while the advertised interest rate never changes.
Last updated . Data as of 23 August 2026.
Dealer-fee loan model
Fee goes into the principal, where the lender puts it.
— Monthly payment
— Amount financed
— Total paid
— Cost above cash
Not a loan offer. Compare total paid, not the monthly payment.
HyreSolar does not originate, broker or sell finance.
How to read what came back
Financed amount is the number that matters, and it is not the price you were quoted. When a dealer fee is expressed as a percentage of the amount financed, the arithmetic is not "add 20%", it is "divide by 0.80". A $30,000 system with a 20% fee means borrowing $37,500, because the fee is itself part of what you borrow.
A low advertised rate and a large dealer fee can cost more than a higher rate and no fee. That is the whole reason this tool exists. Compare the total paid line, not the interest rate and not the monthly payment.
The cost above cash line is the honest comparison. It is what you pay beyond the system price, combining fee and interest into one figure. At the defaults it is $29,320 on a $30,000 system, which is very nearly the price of the system again.
No dealer feeRare in the dealer-financed market and worth actively seeking. Ask directly what the cash price is and whether it differs from the financed price.
10 to 20% feeThe common band. At 20% you are borrowing a quarter more than the system costs, before any interest.
Over 25% feeThe financed price is a third above the cash price. Ask for the cash price in writing and compare it against a credit union or home equity option.
How to use this calculator
Every input below is a number you can find, not one you have to guess. This is where each one comes from.
- 01
Enter the cash price of the system
The price if you paid outright with no financing. This is the number you are trying to protect.
Where to find it Ask the installer directly: "what is the cash price?" If the answer is the same as the financed price, ask specifically whether a dealer fee is included in the financed amount. A cash price that is lower than the financed price is the fee made visible.
- 02
Enter the dealer fee as a percentage
The fee lenders charge installers to originate a low-rate loan, which is passed through to you inside the financed amount rather than shown as a line item.
Where to find it It is frequently not disclosed as a percentage anywhere. The reliable way to find it is the gap between the cash price and the financed price. If cash is $30,000 and financed is $37,500, the fee is 20% of the financed amount.
- 03
Enter the APR
The headline rate on the loan documents. Note that this is the rate applied to the inflated principal, which is why a very low rate can still be expensive.
Where to find it The loan agreement, not the sales presentation. Federal disclosure requires it in the credit documents.
- 04
Enter the term in years
Solar loans commonly run 20 or 25 years. A longer term lowers the payment and raises the total substantially.
Where to find it The loan agreement. Compare a 12-year and a 25-year quote on total paid rather than on payment, because the shorter one usually costs far less overall.
- 05
Compare total paid, not monthly payment
The monthly payment is the number the sale is built around and it is the least informative figure on the page.
Where to find it Run the tool twice, once with the fee and once without, and read the difference in the total. That difference is what the fee costs you.
How this calculator works
Gross up for the dealer fee
Financed = cash ÷ (1 − fee). A 20% fee on $30,000 means borrowing $37,500, not $36,000.
Amortise the financed amount
Standard monthly amortisation at the stated APR over the stated term.
Total the payments
Monthly payment × number of months.
Subtract the cash price
What remains is everything you paid above the system itself: fee plus interest.
The formula, in full
financed = cash ÷ (1 − fee). r = APR ÷ 12. n = years × 12. payment = financed × r × (1+r)^n ÷ ((1+r)^n − 1). total = payment × n. cost above cash = total − cash.
A worked example, start to finish
A $30,000 system sold with a 20% dealer fee on a 25-year loan at a 3.99% headline APR, a combination that appears routinely in residential solar finance.
Inputs
- Cash price
- $30,000
- Dealer fee
- 20% of financed
- Amount financed
- $37,500
- APR
- 3.99%
- Term
- 25 years, 300 payments
- Monthly payment
- $198
Result
$59,320 total
You pay $29,320 above the cash price, very nearly the price of the system a second time. Of that, $7,500 is the dealer fee and the rest is interest on money borrowed to pay the dealer fee. The advertised 3.99% is entirely true and tells you almost nothing.
How the answer moves
The same $30,000 system. Every figure is computed by the calculator on this page.
| Structure | Financed | Monthly | Total paid | Above cash |
|---|---|---|---|---|
| Base case20% fee, 3.99%, 25 yr | $37,500 | $198 | $59,320 | $29,320 |
| No dealer fee, 3.99%, 25 yr | $30,000 | $158 | $47,456 | $17,456 |
| 30% fee, 3.99%, 25 yr | $42,857 | $226 | $67,794 | $37,794 |
| No fee at 7.99%, 25 yr | $30,000 | $231 | $69,404 | $39,404 |
| 20% fee, 3.99%, 12 yr | $37,500 | $328 | $47,252 | $17,252 |
Two rows are worth sitting with. A 20% fee at 3.99% costs $59,320 while no fee at 7.99% costs $69,404, so the low rate really is cheaper here, but only by comparing totals could you know. And shortening the same fee-laden loan to 12 years saves $12,068 despite a much higher payment.
What moves this number most
Ranked. A proposal can change any of these without saying anything untrue, so these are the inputs to check first.
The term
A 25-year loan at these terms costs $59,320; the same loan over 12 years costs $47,252. Longer terms are sold on affordability and cost you $12,068 for the privilege.
The APR
Real but frequently the smallest of the three. The industry uses a low APR as the headline precisely because the fee and the term do more work.
Whether a cash price exists at all
Some installers quote one price regardless. Others have a genuine cash discount, which is the dealer fee made visible. Always ask, and ask in writing.
What the loan is secured against
Not in this model but material. Many solar loans place a lien on the equipment, which surfaces at resale. See what a UCC-1 filing actually does.
The comparison you are not being offered
A credit union personal loan or a home equity line has no dealer fee at all. It may carry a higher rate and still cost less. This tool lets you check rather than assume.
Common mistakes with this calculation
Adding the fee instead of dividing by it
A 20% fee on $30,000 is not $36,000. Because the fee is a percentage of the amount financed, and the fee is itself financed, the correct figure is $30,000 ÷ 0.80 = $37,500. The difference is $1,500 before any interest.
Comparing loans on the monthly payment
The payment is a function of term as much as of cost. A 25-year loan looks cheaper monthly than a 12-year one while costing $12,068 more. Compare total paid.
Believing a low APR means a cheap loan
The advertised rate is applied to an inflated principal. A 3.99% loan on $37,500 and a 7.99% loan on $30,000 are much closer than the rates suggest, and which wins depends on the numbers, not on the headline.
Not asking for the cash price
It is the single most useful question in the whole transaction and it is rarely volunteered. The gap between cash and financed is the fee.
Treating the loan as a bill swap
The pitch is that the loan payment replaces your electricity bill. It rarely replaces all of it, the payment does not fall when the sun does not shine, and the loan outlives the honeymoon. See what actually happens to the first bill.
Ignoring what happens if you sell
A financed system with a lien is a transaction the sale has to deal with. Read loans and leases at the point of sale before you sign a 25-year term on a house you may not keep.
Important: this is a planning estimate
- Not a loan offer, a rate quote or a credit decision.
- Assumes the dealer fee is a percentage of the amount financed, which is the common structure but not the only one.
- Ignores origination costs outside the dealer fee, prepayment terms and any rate step-up.
- Ignores the re-amortisation many solar loans apply if you do not make a lump-sum payment in year one.
- Does not model the tax credit, which is $0 for systems placed in service after 31 December 2025.
Questions this calculator answers
What is a solar dealer fee?
A fee the lender charges the installer to originate a below-market interest rate, which the installer passes to you by raising the financed price. It is typically 10 to 30% of the amount financed and is usually not shown as a line item. The CFPB has found hidden fees in this market typically running 10 to 30% of the cash price and sometimes above 50%.
How do I find out what dealer fee I am being charged?
Ask for the cash price in writing and compare it with the financed price. The gap is the fee. If an installer will not give you a cash price, or says it is identical to the financed price, that is itself informative, the fee is in both, and you are paying it either way.
Why is a 20% fee on $30,000 equal to $37,500 rather than $36,000?
Because the fee is a percentage of the amount financed, not of the cash price, and the fee is itself part of what you finance. The correct arithmetic is $30,000 ÷ (1 − 0.20) = $37,500. Adding 20% to the cash price understates the fee by $1,500 before any interest is applied.
Is a low APR with a dealer fee better than a higher APR with none?
Sometimes, and you cannot tell without running both. At our defaults, 3.99% with a 20% fee costs $59,320 while 7.99% with no fee costs $69,404, so the low rate wins. Change the fee to 30% and the picture shifts. Compare total paid, never the rate.
Should I take a shorter term?
It usually costs far less. The same $37,500 financed at 3.99% costs $59,320 over 25 years and $47,252 over 12, a saving of $12,068 for a payment that rises from $198 to $328. Whether you can carry the higher payment is a separate question from whether it is cheaper.
Can I use a home equity loan or credit union loan instead?
Frequently yes, and it removes the dealer fee entirely because there is no installer origination to subsidise. The rate is often higher and the total often lower. This calculator lets you compare the two properly by entering each structure and reading the total paid line.
What is the "cost above cash" figure?
Total paid minus the cash price. It combines the dealer fee and all interest into a single number representing everything you spent beyond the system itself. At the defaults it is $29,320 on a $30,000 system, which is close to buying the system twice.
Does this include the federal tax credit?
No. The residential credit under §25D is $0 for property placed in service after 31 December 2025, so there is nothing to include for most 2026 installations. Many solar loans are structured assuming you will apply a credit as a lump sum in year one and will re-amortise upward if you do not, check whether yours does.
Does the loan put a lien on my house?
Usually not on the house, but commonly on the equipment, through a UCC-1 financing statement. That surfaces during a sale or refinance. Our page on UCC-1 filings explains what is actually filed, how consumer-goods termination works automatically within a month, and how to self-file and claim $500 if it is not released.
The salesperson says the loan payment replaces my electricity bill. Is that true?
Rarely in full. Solar offsets kilowatt-hours, but a residential bill also carries fixed charges and delivery, and our own measurement puts delivery at 53.2% of the bill across 14.7 million customers. You should expect a smaller electricity bill plus a loan payment, and you should model both together rather than accepting a swap.
The research behind these numbers
Every assumption in this calculator is argued from primary sources somewhere in our research library. These are the pages that matter for this one.
- What zero-down actually costs The CFPB’s finding that hidden fees typically run 10 to 30% of the cash price, and sometimes above 50%.
- The UCC-1 lien on your system What gets filed against the equipment, how consumer-goods termination works and how to self-file.
- Selling a house with a financed system What a 25-year term means if you move in year eight.
- Door-to-door sales rules The federal cooling-off rule that applies even when you invited them, and why Saturday counts.
- Your first bill after solar Why the loan payment rarely replaces the whole bill: delivery is 53.2% of it.
- Solar sales regulation by state Which states require disclosure of financing terms, and which do not.
More solar calculators
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Who would claim the federal homeowner credit under cash, loan, lease or PPA. State programmes: DSIRE.
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Solar contract red-flag checker
Tick the expensive clauses. A count of questions to ask, not a fraud verdict.
Want a more accurate estimate for your home?
Actual results depend on roof, usage, utility rules and a real proposal. Matching is still being built. The form is an enquiry, not a dispatch line.
Written and audited by
HyreSolar Research
Primary-source research, data analysis and fact checking
We are a research desk, not a sales floor. We read the statute, the tariff, the code section, the federal filing or the manufacturer data sheet ourselves, and we publish the figure with the document it came from and the date we retrieved it. Where a number cannot be traced to a primary source, we publish the shorter page and say what we could not verify. That rule has cost us whole sections, and it is the reason the rest can be trusted.
- 160
- primary sources read and cited
- 220
- figures with a retrieval date
- 115
- federal and state government sources
- 66
- researched pages published
How this desk works
- Primary sources only. Statutes from the legislature’s own publishing system, federal data from the agency that collects it, code text from the adopted edition, manufacturer claims from the data sheet. We do not cite an article that cites a source; we go and read the source.
- Every figure carries its provenance. A named document and the date we retrieved it, so you can check it and so you know how old it is. Retrieval dates are not decoration: an EIA rate from May is a different fact from an EIA rate from August.
- We publish what we could not verify. Every research page carries a section naming the things we tried to establish and could not, and why. A paywalled standard, a state website that refused the request, a manufacturer that publishes no figure at all.
- We separate measurement from modelling from our own reasoning, and label which is which on the page. A laboratory measurement, an assumption inside a modelling tool and our own inference are three different kinds of claim and they are never presented as one.
- We do not sell solar, and we take no payment for placement, ranking or a favourable mention. Nobody buys a position on this site.
Data as of 23 August 2026. Authorship on this site is organisational: the analysis belongs to the desk rather than to a named individual, and we do not publish credentials we do not hold. Our editorial policy sets out how we source, date and correct what we publish.
Data and sources
- Issue Spotlight: Solar lending practices (CFPB, retrieved 2026-08-23. Source for hidden fees typically 10–30% of cash price, sometimes above 50%.)
- Residential Clean Energy Credit (§25D) (IRS, retrieved 2026-08-11. Basis for excluding a federal credit from this model.)
- U.S. Solar Photovoltaic System Cost Benchmark (NREL, retrieved 2026-08-16. Context for the $30,000 default cash price.)