✦ Company complaint letter guide
BT complaint letter: broadband, mobile and billing
Create a structured BT complaint letter for broadband faults, mobile issues, billing disputes, cancellation problems or poor customer service.
Choose the problem
Start with the BT issue that matches your complaint
Telecom complaints need clear service dates, account numbers, fault references and the practical impact.
Broadband outage
Use this when broadband or phone service is down, intermittent or repeatedly unstable.
Start this complaint →Slow broadband
Use this when speeds are consistently below what was sold or expected.
Start this complaint →Billing dispute
Use this if charges, direct debits, roaming fees or final bills are disputed.
Start this complaint →Cancellation problem
Use this if cancellation was delayed, ignored or followed by further charges.
Start this complaint →Early termination charge
Use this where an exit fee appears wrong or unfairly applied.
Start this complaint →Poor complaint response
Use this where responses are delayed, inconsistent or do not address the complaint.
Start this complaint →Complaint route
How a telecom complaint should progress
Complain to the provider first and keep evidence of faults, charges and customer service contact.
Complain to the provider first
Give account details, fault references, dates, charges and the outcome requested.
Ask for deadlock if stuck
If the provider will not resolve the issue, ask for its final position or deadlock letter.
Escalate if unresolved
If unresolved after the relevant waiting period or deadlock, use the provider’s ADR route if the complaint is in scope.
Check the provider page because telecom ADR scheme membership can vary.
Evidence checklist
What to include for each BT complaint type
Use the checklist to make the letter specific enough for the company to investigate and respond.
| Complaint type | Evidence to include | Likely outcome to request |
|---|---|---|
| Broadband outage | Account number, outage dates, speed tests, fault references and screenshots. | Service fix, bill credit or compensation where appropriate. |
| Slow broadband | Speed tests, router checks, contract details and fault reports. | Technical review, service fix or cancellation route. |
| Billing dispute | Bills, tariff details, payment history and previous replies. | Corrected bill, refund or account credit. |
| Cancellation problem | Cancellation request, notice date, bills and chat transcripts. | Contract correction, refund and confirmation of closure. |
| Early termination charge | Contract, notice, final bill and fee calculation. | Fee review, correction or refund. |
| Poor complaint response | Complaint reference, response dates and unresolved points. | Substantive response, deadlock or escalation. |
- Evidence to include
- Account number, outage dates, speed tests, fault references and screenshots.
- Likely outcome to request
- Service fix, bill credit or compensation where appropriate.
- Evidence to include
- Speed tests, router checks, contract details and fault reports.
- Likely outcome to request
- Technical review, service fix or cancellation route.
- Evidence to include
- Bills, tariff details, payment history and previous replies.
- Likely outcome to request
- Corrected bill, refund or account credit.
- Evidence to include
- Cancellation request, notice date, bills and chat transcripts.
- Likely outcome to request
- Contract correction, refund and confirmation of closure.
- Evidence to include
- Contract, notice, final bill and fee calculation.
- Likely outcome to request
- Fee review, correction or refund.
- Evidence to include
- Complaint reference, response dates and unresolved points.
- Likely outcome to request
- Substantive response, deadlock or escalation.
Outcome request
What you can ask BT to do
The strongest complaint letters state the practical result you want, not just what went wrong.
Use this page to prepare a clear, firm complaint to BT. Whether your issue involves a BT broadband fault, billing dispute, overcharging, cancellation problem, compensation claim, or poor customer service, the aim is to summarise what happened, what you want done, and the evidence supporting your position.
What this BT complaint letter should achieve
- Clearly state the problem with dates, account numbers, and reference IDs.
- Explain the impact (loss of service, financial loss, business disruption, or inconvenience).
- Request a specific remedy (refund, credit, contract correction, compensation, or service fix).
- Set a clear deadline for response and outline escalation if unresolved.
Common issues people complain to BT about
- Broadband not working or slow speeds
- Overcharging or incorrect bills
- Early termination or cancellation disputes
- Missed engineer appointments
- Compensation for prolonged outages
Keep your complaint focused on the main issue. Avoid including unrelated grievances, as this can weaken clarity.
What to include in your BT complaint
Evidence: Account number, fault reference, outage dates, engineer appointment details, screenshots of speed tests, and copies of bills or previous correspondence.
- Key dates in chronological order (when the issue started and subsequent developments).
- Any complaint or case reference numbers provided by BT.
- Details of what you have already tried (calls, webchat, emails) and the outcome.
Understanding compensation rights
BT is part of the UK’s automatic compensation scheme for certain broadband and landline failures. You may be entitled to fixed daily compensation for delayed repairs, missed engineer appointments, or delayed service activation, without needing to negotiate amounts manually.
What to ask for
- Be specific: state the exact amount claimed or the action required.
- If claiming financial losses, itemise them clearly.
- If seeking automatic compensation, reference the relevant service failure.
- If you want a formal apology or assurance of corrective action, state this explicitly.
Escalation and timeframes
Expected response time: Allow BT up to 8 weeks to resolve your complaint. You may escalate sooner if you receive a “deadlock” letter.
If unresolved: Ofcom regulates telecoms providers but does not handle individual complaints. If BT does not resolve your complaint within 8 weeks, or issues a deadlock letter, you can escalate to the relevant Alternative Dispute Resolution (ADR) scheme (such as Ombudsman Services: Communications or CISAS, depending on BT’s scheme membership at the time).
Practical tips for stronger outcomes
- Keep your letter factual, structured, and professional.
- Use short paragraphs and bullet points for dates and costs.
- Retain copies of all communications.
- Record the dates and times of any calls made.
A clear, well-structured complaint improves the likelihood of a faster and more favourable outcome.
BT complaint FAQs
How long should I give BT to respond?
What should I attach as evidence?
What if they do not reply or refuse to resolve it?
How do I structure a complaint about: Broadband fault?
How do I structure a complaint about: Overcharging?
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