A complaint letter is most effective when it identifies the transaction, explains the problem in date order, includes supporting evidence, and asks for a specific remedy. Send it through the business's stated complaints process, then keep proof of what you submitted.

This guidance is for U.S. consumer disputes. Return policies, warranties, contracts, state laws, and agency procedures can set different requirements. A normal customer-service letter doesn't create a legal deadline or guarantee a refund.

Start with the company's own process

Check the return, exchange, warranty, cancellation, shipping, or billing terms before you write. Many stores won't take returns or exchanges after a set window, such as 30 or 90 days, so the policy that governs the purchase matters more than the letter itself.

Contact the store, website, provider, or account support team first unless a safety or fraud issue requires a different route. Move to email, an online form, or a mailed letter when an informal request hasn't solved the problem or you need a clear record.

If that still fails, ask for a supervisor or complaints department. After that, use the regulator, payment-dispute channel, or court process that actually fits the issue.

The Federal Trade Commission's guide to resolving problems with a business recommends being clear about what you want, explaining the problem to each person you contact, and keeping notes throughout.

What to gather before writing

Vague letters are hard to investigate. Collect the details the business will need to look up the transaction:

Save copies rather than sending original documents. Redact extra card numbers, bank details, account numbers, and government identification. Never include a password or one-time security code.

What to put in the letter

If you're writing under time pressure, stick to this sequence:

  1. Subject: identify the issue and the order or account number.
  2. Opening: say what you bought, when you bought it, and how much you paid.
  3. Facts: describe what happened in chronological order.
  4. Prior contact: state when and how you tried to resolve it.
  5. Remedy: say exactly what you want the business to do.
  6. Evidence: list the attached documents or files.
  7. Response date: request a reply by a specific calendar date.
  8. Contact details: provide a phone number or email and ask for written confirmation.

A calendar date is clearer than "within 14 days." Treat that date as your requested response time unless a contract, law, or agency rule sets a different deadline.

Complaint letter template

The FTC sample customer complaint letter uses the same basic approach: polite language, transaction details, a description of the problem, and a clear request.

Subject: Complaint about [product or service] - [order or account number]

Dear [name or customer service department]:

I am writing about [transaction]. On [date], I [purchased, booked, or paid for] [product or service] from [business] for [$amount]. The order, invoice, or account reference is [number].

The problem is [brief factual description]. It first occurred on [date]. I contacted [person or department] on [date] by [phone, email, chat, or form], and the result was [short summary of the response].

I am requesting [specific remedy]. The attached [receipt, photographs, messages, warranty, or other evidence] supports my account.

Please reply by [calendar date] with the proposed resolution or the next step. If another department handles this issue, please forward my complaint and confirm the correct contact.

Please contact me at [phone number or email]. I would appreciate written confirmation of the outcome.

Sincerely,
[Full name]
[Mailing address, if useful]
[Phone number]
[Email address]

Keep a simple dispute focused on one main problem. If several issues involve the same transaction, list each one briefly and state the remedy you want for each.

How to make the letter persuasive

Lead with verifiable facts

Replace conclusions with details. "Your service was terrible" gives the recipient little to investigate. A stronger version is:

On April 1, I purchased a [model] for $350 at your store. The item stopped working on [date]. I contacted the store on [date] and was told [response]. I am requesting [refund, repair, or replacement].

The date, price, product, and previous response give the business a starting point.

Ask for one practical remedy

Say what would resolve the dispute. You might request:

If you would accept more than one outcome, explain your preference: "I prefer a replacement, or a refund if a replacement is unavailable."

Keep the tone calm and firm

Politeness doesn't mean accepting a poor response. Avoid insults, threats, accusations you can't support, and long emotional descriptions. Don't claim that a company violated a law unless you've verified that the law applies to your transaction and location.

A U.S. complaint should not cite the U.K. Consumer Rights Act 2015 or an unspecified "2026 reform." U.S. consumer protections can depend on the state, product, contract, and payment method.

Send the complaint and preserve a record

Use the channel named in the receipt, terms, warranty, privacy policy, or customer-service page. If the business has a formal complaints form, use it and include the case number from any earlier contact.

Before you click submit, save a copy or take a screenshot of the completed form. The FTC specifically recommends preserving a screen copy when filing a complaint online. Also keep:

If a representative calls, send a short follow-up email summarizing what was agreed. Those records matter if you later contact a regulator, payment provider, or court.

If the business doesn't respond

Wait until the response date you requested unless another deadline requires faster action. Then send a brief follow-up that includes the date of your original complaint, the order or case number, the remedy you requested, a copy of the original letter, and a new request for a written response.

If the reply is incomplete, state what remains unresolved instead of restarting the entire story. Ask for the name of the department or supervisor handling the next review.

A 14-day or 30-day response period is not a universal rule for every U.S. complaint. Some agency and dispute-resolution processes have their own time frames, but those do not automatically apply to an ordinary letter sent to a business.

Choose the right escalation route

Escalation should match the type of dispute.

Bank complaints

Start with the bank or financial institution and keep the bank's response. For complaints covered by its process, the FDIC consumer complaint process asks consumers to provide a detailed written description in chronological order, including names, phone numbers, transaction dates, and amounts.

The FDIC says its Consumer Response Unit generally responds within 14 days. That describes the FDIC's process; it is not a 14-day deadline for every bank or financial company.

Suspected fraud or deception

An ordinary service failure is different from suspected fraud, identity theft, or deceptive conduct. Preserve advertisements, receipts, messages, payment records, and account notices. The FTC consumer guidance includes a separate route for reporting fraud or deception. A report is a separate step from asking the business directly for a refund or correction.

Better Business Bureau complaints

The BBB can be an additional dispute channel for some business complaints. Its complaint process says complaints are generally closed within 30 days and that consumers are notified of the business's response or lack of response.

BBB is not a government agency or a court, and it doesn't handle every type of complaint. A BBB submission does not guarantee a refund, legal finding, or required business response.

Privacy complaints under a specific framework

If your complaint concerns an organization covered by the EU-U.S. Data Privacy Framework, BBB National Programs describes a separate Data Privacy Framework complaint process. It says the business must respond within 45 days. That route applies to covered privacy practices, not to every data breach or privacy concern.

Small claims and other formal action

If the amount is significant and internal efforts fail, check your state's official court guidance for small-claims limits, filing rules, service requirements, and deadlines. The FTC notes that dollar limits vary by state and that some states set the limit as high as $25,000. Don't assume that sending a complaint letter extends a warranty, preserves a billing-dispute period, or pauses a court deadline.

Situations that need a different process

Some problems shouldn't be handled only as customer-service complaints:

Common mistakes to avoid

Before you send

Confirm that the letter identifies you and the business, names the product or service and transaction reference, states the facts in date order, explains what went wrong, lists the evidence you attached, requests a specific remedy, includes a reasonable response date, and uses a professional tone. Strip out extra sensitive information, then save a copy.

Pull the receipt, the policy page, and any case numbers you already have. Fill in the template with dates and one specific remedy, send it through the channel the business names, and save the screenshot or sent-mail copy before you close the window.