A Formal Letter of Complaint B2 Writing Practice Tests Rules & Examples

How to Write a Formal Letter of Complaint in English

A formal letter of complaint is a piece of writing in which you express dissatisfaction with a product, service, or situation to an organisation or company. You write this type of letter when you have experienced a problem that has not been resolved informally, and you wish to request action or compensation. In real life, people write formal complaint letters to hotels, airlines, shops, utility companies, and educational institutions, among others.

At B2 level, you are expected to write a well-structured, appropriately formal letter of approximately 140–190 words. You must use the correct layout, maintain a consistent formal register throughout, and clearly state your complaint, explain its impact, and request a specific remedy. This is a common task in the Cambridge B2 First (FCE) Writing examination.

Essential Writing Rules & Sentence Structure

1. Formal Letter Layout

A formal complaint letter must follow a strict conventional layout. The key structural elements are:

• Salutation: Use Dear Sir or Madam, when you do not know the recipient's name, and sign off with Yours faithfully,. Use Dear Mr Davis, when you know the name, and sign off with Yours sincerely,.
• Opening paragraph: State your reason for writing immediately and clearly.
• Body paragraphs: Describe the problem in detail and explain the consequences or inconvenience caused.
• Closing paragraph: State what action you expect the company to take and by when.
• Sign-off: Use the correct formal closing phrase followed by your full name.

2. Maintaining a Formal Register

Register consistency is essential in a formal complaint letter. You must avoid contractions (don't, can't, I'm), colloquial expressions, and informal phrasal verbs. Use formal vocabulary and full grammatical forms throughout.

• Write I do not rather than I don't.
• Write I would be grateful if you could investigate this matter rather than Please look into this.
• Write I was unable to tolerate rather than I couldn't put up with.

3. Using the Passive Voice for Objectivity

The passive voice creates a more impersonal and objective tone, which is appropriate in formal complaint letters.

• I was informed that the item had been dispatched.
• No explanation was provided for the delay.
• A full refund has not yet been issued.

4. Punctuation with Discourse Markers

Always place a comma after sentence adverbs and discourse markers that introduce a clause or sentence.

• Furthermore, the staff member was dismissive of my concerns.
• Consequently, I was unable to use the service I had paid for.
• Nevertheless, I am willing to accept a replacement rather than a refund.

5. Expressing Complaints Firmly but Politely

Effective formal complaint letters are assertive without being aggressive. Use polite but direct structures to communicate dissatisfaction and state expectations clearly.

• I am writing to express my dissatisfaction with...
• I would be grateful if this matter could be resolved at your earliest convenience.
• I trust that you will treat this matter with the urgency it deserves.

Useful Linking Words (Connectors)

The following connectors will help you organise your complaint letter clearly and demonstrate a sophisticated command of English at B2 level.

Model Writing Sample: A Formal Letter of Complaint About a Hotel Stay

The following model letter is written in response to this Cambridge-style prompt:

You recently stayed at the Grand View Hotel for a business trip. You were dissatisfied with several aspects of your stay. Write a letter to the hotel manager explaining your complaints and requesting appropriate action. Write your letter in 140–190 words.

Dear Sir or Madam,

I am writing to express my considerable dissatisfaction with the standard of service I received during my recent stay at the Grand View Hotel from 14th to 16th March.

Upon arriving at my room, I discovered that it had not been cleaned to an acceptable standard. The bedding appeared unchanged and the bathroom floor was visibly dirty. Furthermore, despite having reserved a quiet room for business purposes, I was allocated a room directly above the hotel bar, making it impossible to sleep before midnight on both evenings.

In addition to this, I was informed at check-in that the advertised business centre was temporarily out of service. Consequently, I was unable to prepare for an important client presentation, which caused me considerable professional embarrassment.

In light of the above, I would be grateful if you could arrange a full or partial refund at your earliest convenience. I trust that you will treat this matter with the seriousness it deserves.

Yours faithfully,

James Thornton

Model Text Breakdown

Key Phrases & Sentence Starters

Opening the Letter & Stating Your Purpose

• I am writing to express my dissatisfaction with...
• I am writing to draw your attention to a serious problem regarding...
• I am writing with reference to my recent stay at / purchase from / visit to...
• I feel it is necessary to bring the following matter to your attention.

Describing the Problem in Detail

• Upon arriving, I discovered that...
• I was extremely disappointed to find that...
• Despite the fact that I had specifically requested..., no arrangements had been made.
• I was informed by a member of staff that...
• The situation was further aggravated by the fact that...
• Not only was the service unsatisfactory, but the facilities were also...

Explaining the Consequences & Impact

• As a consequence, I was unable to...
• Consequently, this caused me considerable inconvenience.
• This resulted in significant disruption to my plans.
• I was left with no alternative but to...

Requesting Action & Closing the Letter

• I would be grateful if you could arrange a full refund at your earliest convenience.
• I would appreciate it if this matter could be investigated promptly.
• I trust that you will take the appropriate steps to resolve this situation.
• I look forward to receiving your response within the next fourteen days.
• I expect to hear from you at your earliest convenience.
• In light of the above, I request that...

Common Writing Mistakes to Avoid

❌ I am writing to complain about the hotel, the room was dirty and the staff were rude.
✅ Avoid comma splices. Use a full stop or a conjunction to separate two independent clauses.
I am writing to complain about the hotel. The room was dirty and the staff were extremely unhelpful.

❌ I couldn't put up with the noise, so I asked them to sort it out.
✅ Avoid informal phrasal verbs and contractions in formal letters. Use formal vocabulary.
I was unable to tolerate the noise; consequently, I requested that the matter be resolved immediately.

❌ Despite of my repeated complaints, nothing was done.
✅ 'Despite' is followed directly by a noun or gerund — never by 'of'. Use 'In spite of' if you find 'despite' difficult to remember.
Despite my repeated complaints, nothing was done. or In spite of my repeated complaints, nothing was done.

❌ Furthermore the manager refused to offer any compensation.
✅ Always place a comma after discourse markers such as 'Furthermore', 'Moreover', 'Consequently', and 'Nevertheless' when they introduce a main clause.
Furthermore, the manager refused to offer any compensation.

❌ Dear Sir or Madam, ... Yours sincerely, James Thornton
✅ When you open with 'Dear Sir or Madam' (unknown recipient), you must close with 'Yours faithfully'. 'Yours sincerely' is only used when you know and have addressed the recipient by name (e.g. 'Dear Mr Davis').
Dear Sir or Madam, ... Yours faithfully, James Thornton

Writing Checklist & Practice Task

B2 Formal Letter of Complaint — Writing Checklist

• ☐ I have used the correct salutation (Dear Sir or Madam / Dear Mr [Name]).
• ☐ I have used the correct sign-off (Yours faithfully / Yours sincerely) consistently with my salutation.
• ☐ My opening paragraph clearly states why I am writing and includes a reference to the specific event or purchase.
• ☐ I have described at least two specific complaints with relevant details.
• ☐ I have explained the consequences or inconvenience caused by each problem.
• ☐ I have used at least three different formal connectors (e.g. Furthermore, Consequently, In addition to this).
• ☐ I have avoided all contractions, informal phrasal verbs, and colloquial language throughout.
• ☐ I have placed commas correctly after discourse markers and sentence adverbs.
• ☐ I have used the passive voice at least once to create an impersonal, formal tone.
• ☐ My closing paragraph makes a clear, polite, and specific request for action or compensation.
• ☐ My letter is between 140 and 190 words (not including the salutation and sign-off).
• ☐ I have checked for comma splices, spelling errors, and tense consistency.

Practice Writing Task

Read the following Cambridge B2 First-style writing prompt and write your response.

You recently purchased a laptop computer from an online retailer called TechDirect. When the laptop arrived, it was damaged, several advertised features were not working, and the delivery was five days late. You contacted customer services by telephone but received no satisfactory response.

Write a formal letter of complaint to the manager of TechDirect. In your letter, you should:

• describe the problems with the laptop and the delivery
• explain what happened when you contacted customer services
• state clearly what action you expect the company to take

Write your letter in 140–190 words in an appropriate style.

Now test your writing mechanics and sentence skills in the exercises below.