Can AI write a complaint letter that gets results?
Yes — AI can write a complaint letter that gets read, and it does the drafting in a couple of minutes. The skill of how to write a complaint letter is mostly structure: state the problem, name the outcome you want, give key dates, show what you have already done, and set a deadline. A general assistant handles that structure well. What it cannot do is know what actually happened to you, so the level for this task is "AI drafts, you finish."
Tools that work
You do not need a specialist "AI complaint letter generator" for this. Any of the main general assistants will draft a short business letter, and the free tiers cover plain text chat, which is all the task needs.
| Tool | Free tier | Paid (as listed) | Useful limits and notes |
|---|---|---|---|
| ChatGPT | Free plan ("Best for trying out ChatGPT") includes unlimited text chats, with limited messages with uploads, limited image creation, limited voice, limited deep research and limited memory | Plus costs $20/month, billed monthly, with no annual billing option (OpenAI help centre); Go is a lower-cost tier with higher limits than Free for image generation, file uploads and data analysis — its price was not rendered on OpenAI's pricing page when checked (Go) | File uploads: 512MB per file, and Free users are limited to 3 file uploads per day (uploads FAQ). You can stop new chats being used to train OpenAI models by turning off "Improve the model for everyone" under Settings > Data controls (data controls) |
| Claude | Free at $0, including chat on web, desktop and mobile, web search, file creation and code execution, memory and Artifacts | Pro at $17 per month with the annual discount ($200 billed up front) or $20 if billed monthly; Max starts from $100 per month | Uploads up to 500MB per file, up to 20 files per chat, PDFs up to 1000 pages (upload help). Usage limits apply to every plan; prices exclude tax and plans may change |
| Gemini | Gemini app free at $0/month with a Google Account | Google AI Plus at $4.99/month; Google AI Pro at $19.99/month, listed as 4x higher usage access than Free, plus Gemini in Gmail, Docs and more and 5 TB storage | Prices differ by country; Google's page shows AUD on the Australian version |
Microsoft also offers a limited free version of Copilot, with Microsoft 365 Personal at $9.99/month and Family at $12.99/month (Copilot in Word, Excel, PowerPoint and Outlook with higher usage than free) and Premium at $19.99/month, at US prices on Microsoft's page (Copilot pricing).
A free tier is usually enough for one letter, because the work is a short text draft. Paid plans matter if you hit message limits, want to upload a batch of receipts and emails at once, or want the letter drafted inside Word or Gmail. Plans, limits and prices can change, so check the current plan on the tool's site before you pay for anything.
Every one of these tools warns about the same risk. OpenAI says ChatGPT can produce incorrect or misleading outputs, including fabricated quotes or citations (OpenAI). Anthropic says Claude can occasionally produce incorrect or misleading responses and that users should not rely on it as a single source of truth (Anthropic). Google advises double-checking Gemini responses and not relying on them for professional advice (Gemini Apps help). Microsoft says Copilot can make mistakes or produce inaccurate results and advises reviewing and verifying what it creates (Microsoft support).
A prompt to paste
Copy this into the assistant of your choice and fill in the brackets:
Write a formal complaint letter about [product or service] bought from [business name] on [date].
The problem: [2-3 plain sentences describing what went wrong, facts only].
What I have already done: [dates of calls, emails or tickets, and who I spoke to].
The outcome I want: [refund / replacement / repair / cancel the contract / compensation — be specific, e.g. a refund of $AMOUNT to the original payment method].
Key dates to include: purchase [date], fault first noticed [date], contact attempts [dates].
Rules:
- Tone: firm and polite, no insults, no threats, no legal terms or laws I have not given you.
- Length: under one page.
- Structure: what happened, why it is a problem, the outcome I want, a deadline of [5 / 10 / 15] working days, and what I will do next if I do not hear back.
- Open with my name and my account or order number [number]. Close with my phone number and email.
- Do not invent dates, amounts, laws, case numbers or quotes. If something is missing above, write [FILL IN: ...] instead.
Two follow-ups that are usually worth running:
- "Shorten this so I can paste it into the business's online contact form."
- "Rewrite the remedy paragraph to say I am rejecting the product, that I consider the problem major, and that I want a refund rather than a repair. Keep everything else identical."
How far AI gets you
AI drafts, you finish. The assistants' own help pages tell you their output can be wrong, and a complaint letter is only as strong as the dates, amounts and remedy in it — details that exist in your receipts and emails, not in the model.
What you still do
- Check every fact. Dates, order numbers, amounts, product names and what the business told you. Read the letter line by line as if you were the person receiving it.
- Choose the remedy and say it clearly. The ACCC describes remedies under Australian consumer law as a free repair, replacement or refund, or cancelling or changing a contract, and possibly compensation for damages and loss. Where a product has a major problem, you have the right to choose a replacement or a refund, and the ACCC advises telling the business that you are rejecting the product, which remedy you want, and why you consider the problem major.
- Set a deadline, and say what happens next. The ACCC's free complaint letter tool sets a response deadline of 5, 10 or 15 working days, after which you will lodge a formal complaint with your state or territory consumer protection agency (for example NSW Fair Trading or Consumer Affairs Victoria) and/or report the matter to the ACCC. Its letter also asks you to describe the problem and the outcome you want, include key dates, say what you have already done and what you will do if it stays unresolved, ask for a response within a reasonable time, and attach supporting documents such as a receipt or invoice.
- Send it, and keep a copy. Keep the letter, the attachments and the proof of sending. If you upload a receipt or an email thread to an assistant, use the tool's data controls — in ChatGPT, for example, you can turn off "Improve the model for everyone," and temporary chats are not used to improve models.
- Escalate to the right body once the deadline passes. The sources here are Australian, but the pattern — business first, then an independent scheme — is what to look for wherever you live:
- Financial firms: AFCA is a free, fair and independent service for complaints about financial firms that are AFCA members (credit, insurance, banking, super, investments and financial advice). The first step is usually to raise the problem with the firm directly. AFCA may be unable to help if a court has already decided the matter, the issue is outside its rules or time limits, or the firm is not an AFCA member.
- Phone or internet: the Telecommunications Industry Ombudsman asks you to raise the problem with your provider first — skipping that step adds five extra days to your case. After the TIO escalates a complaint, the provider proposes a resolution within 10 working days, and the TIO says 80% of complaints are resolved at this stage.
- Get human help for the legal parts. The ACCC states that it does not resolve individual complaints or provide legal advice on your rights and obligations. If your claim involves a contract, insurance, a large sum, a deadline you are unsure about, or a business that has threatened legal action, use your local government consumer protection agency or a licensed lawyer, and check the rules that apply in your country or state.
Common questions
Can I send the AI's letter without editing it?
No. Read it once against your own records first. The assistants' own help pages say their output can be inaccurate or misleading, and a letter with one wrong date or a remedy you did not actually ask for gives the business an easy reason to delay.
Do I need a paid plan to write one letter?
Usually not. The free tiers of ChatGPT, Claude and Gemini include ordinary text chat, which is what drafting a letter needs. Paid plans are about higher usage limits, larger or more numerous file uploads, and features like drafting inside Word or Gmail.
What if the business never replies?
Send one follow-up after your deadline passes, then escalate. Depending on the sector and where you live, that means a consumer protection agency, an ombudsman or an independent complaints scheme such as AFCA for financial firms or the TIO for phone and internet providers in Australia.