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Supplemental Insurance Claim Letter

For a claim the insurer accepted but paid short: a letter and a sheet that set every line of its estimate against your contractor's numbers.

Context to provide

Rather fill it in yourself? Download (.docx + .csv) · No account needed

What you get

One document, with the spreadsheet that goes with it

RiverSupplemental Insurance Claim Letter

Supplemental Insurance Claim Letter

[Your name, or your business's legal name]
[Mailing address]
[Phone] | [Email]

[Date of this letter]

Sent by [certified mail, return receipt requested, or email to the claims address on your claim] [Keep proof of the date you sent it.]

[Adjuster's name], [Adjuster's title]
[Insurance company name]
[Claims department mailing address]

Re: Supplemental claim and request for additional payment

  • Named insured: [Name exactly as it appears on the declarations page]
  • Policy number: [Policy number]
  • Claim number: [Claim number]
  • Date of loss: [Date of loss]
  • Insured property or vehicle: [Property address, or vehicle year, make, model and VIN]
  • Paid to date: [$ total paid, with payment dates]

Dear [Adjuster's name]:

[Insurance company name] accepted coverage for this loss on [date coverage was accepted] and has paid [$ paid to date]. The documented cost to [repair / replace] the covered damage is [$ documented cost], which leaves [$ gap] unpaid. I am submitting this supplemental claim and ask you to revise your estimate and pay the difference.

1. Where the claim stands

  • Your estimate: [$ amount], dated [date], prepared by [adjuster or firm], [estimate or file number]
  • Our estimate or invoices: [$ amount] from [contractor, shop, or vendor], dated [date]
  • Deductible applied: [$ amount]
  • Depreciation withheld: [$ amount] [If the policy pays replacement cost, check what it requires before withheld depreciation is paid, such as proof that repairs are finished.]
  • Payments received: [$ amount on date, check or transfer number]

2. Items missing from or underpaid in your estimate

No.ItemYour estimateOur estimate or invoiceDifferenceWhy it should be paid
1[Room or area, and item or trade][$ amount, or "not included"][$ amount][$ difference][Reason, Exhibit letter]
2[Item][$ amount][$ amount][$ difference][Reason, Exhibit letter]
3[Item][$ amount][$ amount][$ difference][Reason, Exhibit letter]
Total difference[$ total]

[The Line-by-Line Payment Comparison sheet holds every line. Copy only the lines in dispute here. Common gaps are items left out of the scope, lower measurements or quantities, unit prices below local costs, code upgrade work, overhead and profit, and sales tax.]

3. Damage found during repairs

[Describe any covered damage found after your inspection: what it is, where, when it was found, and who found it. Delete this section if none.]

This damage was found on [date found] and photographed before it was covered up (Exhibit [letter]). If you want to reinspect before the work is closed in, please contact me by [date] at [phone or email].

4. Evidence enclosed

  • Exhibit A: Your estimate dated [date] and your payment letters
  • Exhibit B: [Contractor, shop, or vendor] estimate dated [date]
  • Exhibit C: Invoices and receipts for work completed
  • Exhibit D: [Number] photos, including damage found during repairs, taken on [dates]
  • Exhibit E: [Code requirement, permit, manufacturer instruction, or local price quote that supports a line]
  • Exhibit F: Line-by-Line Payment Comparison

5. What I am asking for

  1. Revise your estimate to include the items in section 2 and pay a supplemental amount of [$ amount].
  2. Pay the withheld depreciation of [$ amount], now that repairs are complete (Exhibit C). [Delete if not applicable.]
  3. For any line you do not pay in full, explain in writing the policy provision or pricing source for the lower amount.
  4. If you need anything else to decide, tell me in writing exactly what it is.

6. Response requested

Please respond in writing by [response date]. [Choose a date that fits your state's claim handling time limits. Some states also set a deadline for filing a supplemental claim, counted from the date of loss. These rules vary by state.]

I also ask that [Insurance company name] handle this supplemental claim within the time limits set by [state] law. [Cite a specific statute or regulation only after you have checked it.]

This letter is a supplemental claim and a request for payment. Nothing in it waives any of my rights under the policy or the law, including any appraisal provision the policy contains.

Please send all communication about this claim to [email or mailing address].

Sincerely,

[Signature]
[Printed name]
[Title, if writing for a business]
[Business name, if any]

Enclosures: Exhibits A to [last exhibit letter]
cc: [Your contractor, and your insurance agent or broker, if any]


Notes for you, delete before sending:

  • Many policies have an "Appraisal" condition for disagreements about the amount of loss. Usually each side picks an appraiser and the two pick an umpire. Read your policy's own wording for who pays, the time limits, and what the result decides. This template does not recommend using it or not.
  • If the insurer does not pay or answer, other options include a complaint to your state insurance department, a licensed public adjuster, or a lawyer. Each has different costs and limits. This template does not recommend one.
  • This template is a drafting aid, not legal advice.
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An accepted claim with a short check is a different fight from a denial. Coverage is settled, so the argument is about the amount, and the gap almost never sits in one number. It hides in lines: an item left out, a smaller measurement, a lower unit price, no overhead or tax. The NAIC model unfair claims act treats failing to settle fairly once "liability has become reasonably clear" as an unfair practice, which is exactly where a paid-short claim sits.

The pack has one letter and one sheet. The Line-by-Line Payment Comparison sets each insurer estimate line beside the contractor line for the same work, then carries the subtotal, overhead and profit, tax, withheld depreciation, deductible, and payments down to one supplemental amount. The Supplemental Insurance Claim Letter copies only the disputed lines into a table, reports damage found during repairs, and makes one request with a reply date. Appraisal gets a neutral note, not a recommendation.

Timing rules differ by state, so the letter leaves them blank. Florida, for one, bars a supplemental property claim unless notice reaches the insurer within 18 months after the date of loss, so check your own state's rule and the policy's conditions. Fill the files by hand, or let the insurance claim appeal letter generator fill them from your estimates and invoices. If the insurer refused the claim outright, the insurance claim appeal letter is the right starting point.

What's in the pack

01

Supplemental Insurance Claim Letter

A complete supplemental claim with the claim details and amount paid up top, six numbered sections, an exhibit list, and a signature block for a person or a business.

02

Line-by-Line Payment Comparison

Every insurer estimate line matched to the contractor line for the same work, with the difference, the insurer's reason, your answer, and the exhibit.

03

The summary rows under the lines

Overhead and profit, sales tax, withheld depreciation, the deductible, and payments already made, so the amount requested is the real remaining gap.

04

Damage found during repairs

Section 3 reports hidden damage with the date it was found and the photos, and offers the adjuster a chance to reinspect before it is closed in.

05

A written reason for every short line

Section 5 asks the insurer to name the policy provision or pricing source behind any line it still will not pay in full.

06

A neutral note on appraisal

The closing notes explain in two sentences what an appraisal condition usually does, and leave the choice to you.

How to use it

  1. 1

    Open in River, or download it

    Download the letter as Word and the comparison as CSV and fill them by hand, or open them in River so the agent fills them from your estimates.

  2. 2

    Match the two estimates line by line

    Put each line of the insurer's estimate next to the contractor's line for the same work, and add the items the insurer left out entirely.

  3. 3

    Carry the gap down to one amount

    Fill the summary rows for overhead, tax, depreciation, deductible, and payments received, and check that the supplemental amount adds up.

  4. 4

    Check the timing, then send it yourself

    Check your policy and your state's rules for any supplemental claim deadline, choose a reply date, delete the notes, and send it with proof of delivery.

Frequently asked questions

Is this template free?

Yes. The letter downloads as a Word file and the Line-by-Line Payment Comparison as a CSV, with no signup. Edit with AI is a separate, optional path that creates a free River account and fills both files from your estimates, invoices, and payment letters.

When is a supplemental claim the right letter?

When the insurer accepted coverage and paid, but less than the documented cost of the covered repair, or when repairs uncovered more damage from the same loss. If the insurer refused coverage for the loss itself, the reconsideration request in the insurance claim appeal letter fits better.

Should I invoke the appraisal clause?

This template does not advise either way. The Texas Department of Insurance describes the usual process: each side hires an appraiser, the two choose an umpire, and the result binds both sides on the amount. Policies differ on cost and timing, so read yours, and ask a lawyer or public adjuster if unsure.

Is there a deadline for a supplemental claim?

It depends on the state and the policy. Florida sets one by statute, 18 months after the date of loss for a supplemental property claim. Do not assume the same limit applies elsewhere. Check your policy's conditions and your own state's rules before you rely on any date, and note the one that applies.

Why did the insurer hold back depreciation?

Some replacement cost policies pay the depreciated value first and the rest as repairs are done. States limit this differently: Florida, for example, bars any depreciation holdback on a total loss of a dwelling. The business insurance renewal review checks how your policy values a loss before the next renewal.

What format are the downloaded files?

The letter is a .docx file that opens in Word, Pages, or Google Docs, including its table of disputed lines. The comparison is a .csv file that opens in Excel, Numbers, or Google Sheets. Every blank is a square-bracket placeholder you can fill in by hand.

What does Edit with AI actually do?

It copies this letter and comparison into a new River workspace. River asks for both estimates, the invoices, photos, and the state, fills the comparison line by line, then edits the letter. Anything unconfirmed is marked for you to check. It is a drafting aid, not legal advice, and nothing is sent.

Ask for the rest of the claim, one line at a time

Download the blank letter and comparison as Word and CSV files, or open them in River and fill them from both estimates.

Edit with AI