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How to complain to Three

Generate a structured complaint letter to Three based on your timeline, reference numbers and evidence. Clear, firm, and ready to send.

Billing dispute Service outage Contract / cancellation Poor customer service
Generate a complaint letter (£3) How it works Back to Mobile & broadband Typically ready to send in 2–4 minutes.

How it works

1) Add facts What happened, key dates, and who you spoke to.
2) Pick an outcome Refund / replacement / compensation / correction.
3) Send with confidence Clear structure, calm tone, next steps.

Tip: receipts, screenshots, order numbers, account references, and chat/call notes help — but you can still complain effectively without them.

Escalation and evidence

If you do not get a satisfactory response, you can escalate. The right route depends on the sector and whether the firm uses an ADR/ombudsman scheme.

  • Sector: mobile-broadband
  • Regulator / ombudsman / ADR: Alternative Dispute Resolution (ADR) scheme used by the provider (e.g., Ombudsman Services or CISAS)
  • Typical wait before escalation: Allow the provider a reasonable time to respond; if unresolved, ADR routes are typically available after deadlock or set time limits.
  • Evidence that helps: Account number, contract dates, bills, fault logs/screenshots, and correspondence.

Your letter should request a written response and set a reasonable deadline.

Generate a structured complaint letter to Three

Three complaint guidance

Use this page to prepare a clear, firm complaint to Three. The aim is to summarise what happened, what you want them to do, and the evidence that supports your position.

What this letter should achieve

  • State the problem with dates and reference numbers.
  • Explain the impact (financial, practical, or time lost) in concrete terms.
  • Request a specific remedy (refund, correction, apology, compensation, or service fix).
  • Set a clear deadline for response and next steps if unresolved.

Common issues people complain about (Telecoms)

Typical themes include: Billing dispute, Service outage, Contract / cancellation, Poor customer service. Keep your letter focused on the main issue and avoid adding unrelated grievances.

What to include

Evidence: Account number, contract dates, bills, fault logs/screenshots, and correspondence.

  • Key dates in order (what happened first, next, and most recently).
  • Any reference numbers (booking/order/account/claim IDs).
  • What you have already tried (calls, chats, emails) and the outcome.

What to ask for

  • Be specific: the amount, the action required, or the correction you want.
  • If your losses are quantifiable, itemise them briefly.
  • If you want an apology or assurance, say so explicitly.

Escalation and timeframes

Expected wait: Allow the provider a reasonable time to respond; if unresolved, ADR routes are typically available after deadlock or set time limits.

Escalation route: Alternative Dispute Resolution (ADR) scheme used by the provider (e.g., Ombudsman Services or CISAS). If you reach deadlock or do not receive a meaningful response, you can escalate via the appropriate dispute route for the sector.

Practical tips

  • Keep it factual and polite; avoid insults or speculation about motives.
  • Use short paragraphs and bullet points for dates and costs.
  • Save copies of everything you send and receive.
Generate a structured complaint letter to Three

Three complaints FAQ

How long should I give Three to respond?
Allow the provider a reasonable time to respond; if unresolved, ADR routes are typically available after deadlock or set time limits.
What should I attach as evidence?
Include receipts/statements, reference numbers, screenshots/photos where relevant, and copies of prior correspondence. Only attach what directly supports your key points.
What if they do not reply or refuse to resolve it?
If you reach deadlock or the issue remains unresolved after a reasonable period, consider escalation via: Alternative Dispute Resolution (ADR) scheme used by the provider (e.g., Ombudsman Services or CISAS). You can also consider payment-provider routes (e.g., chargeback) where appropriate.
How do I structure a complaint about: Billing dispute?
State the facts (dates, references), the impact, what you have already tried, and the remedy you want. Keep it limited to the single issue and ask for a written response.
How do I structure a complaint about: Service outage?
State the facts (dates, references), the impact, what you have already tried, and the remedy you want. Keep it limited to the single issue and ask for a written response.
Generate a structured complaint letter to Three

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