How to Write a Formal Letter: KS3 English Step-by-Step Guide

A formal letter follows a specific layout and uses a register that is professional, polite, and precise. Whether you are writing to a headteacher, a local councillor, or an employer, the conventions are consistent — and mastering them at KS3 gives you a skill that transfers directly into adult life and is assessed in GCSE English Language writing tasks.

What makes a letter "formal"?

A formal letter is written in Standard English, using complete sentences, appropriate vocabulary, and a respectful tone. It is the opposite of a text message or an email to a friend. The key features that distinguish formal from informal writing are:

Register: formal vocabulary and no slang, contractions ("it's", "we're") or colloquial phrases ("loads of")

Tone: polite, measured, and professional — even if writing a letter of complaint

Layout: specific conventions for where to place addresses, the date, and the greeting

Purpose: always clear; a formal letter should have one main purpose, stated early

The layout of a formal letter

The layout below is standard in the UK. Each section must appear in the correct position.

[Your address — top right]
[Town, County]
[Postcode]
[Date in full: 16 June 2026]

[Recipient's name and address — left-aligned, below the date]
[Title and Name]
[Organisation]
[Address]
[Postcode]

[Greeting]

[Subject line — optional but useful]

[Body paragraphs]

[Sign-off]
[Your name, printed]

Your address and the date

Place your address in the top right-hand corner of the page. Write the date in full below the address: "16 June 2026" rather than "16/06/26". Do not include your name here — your name appears at the bottom of the letter.

The recipient's address

The name and address of the person you are writing to goes on the left-hand side, below the date. If you know the person's name, use it: "Ms H. Patel, Director of Education." If you do not know the name, use their title: "The Headteacher."

The greeting (salutation)

If you know the recipient's name, open with "Dear Mr/Ms/Dr [Surname]," — note the comma after the salutation.

If you do not know the name, open with "Dear Sir or Madam,"

This choice affects how you close the letter:

Greeting | Closing sign-off
Dear Mr/Ms [Name] | Yours sincerely,
Dear Sir or Madam | Yours faithfully,

This is one of the most frequently tested conventions at KS3: "sincerely" when you know the name; "faithfully" when you do not.

Subject line (optional)

A subject line directly below the salutation is good practice in formal letters, particularly when writing to organisations. Write it in bold or underline it:

Re: Request for Information About the New School Policy

Formal register: what to write and what to avoid

Register means the level of formality of your language. In a formal letter, every word choice matters.

Informal | Formal equivalent
"I want to complain about..." | "I am writing to express my concern regarding..."
"loads of problems" | "a number of significant issues"
"get in touch" | "contact me"
"kids" | "children" / "pupils"
"can't" | "cannot"
"ASAP" | "at your earliest convenience"

Do not use exclamation marks in a formal letter. Do not begin sentences with "And" or "But." Every paragraph should have a clear purpose, and each new idea should begin a new paragraph.

An annotated model letter

The following model letter shows all conventions in practice. It is annotated so you can see exactly what each section is doing.

14 Elmwood Road Sheffield S11 9BT

16 June 2026

The Headteacher Parkside Academy Broad Lane Sheffield S3 7HQ

Dear Mrs Okafor, ← Greeting: name known, so "Yours sincerely" at the close

Re: Request to Extend the School Library Opening Hours ← Subject line: clear and specific

I am writing to request that the school library's opening hours be extended until 5.00 pm on weekdays. ← First paragraph: state purpose immediately

At present, the library closes at 3.30 pm, which means that students who participate in after-school activities are unable to use its resources for independent study. A number of my classmates in Year 9 have found this a significant barrier when preparing for end-of-year assessments. ← Second paragraph: evidence and context

I understand that staffing costs are a consideration; however, I would respectfully suggest that a rota of volunteer sixth-formers, supervised by a member of the library staff, might allow extended hours without placing an undue burden on the budget. I am aware that Fairfield Secondary School in the neighbouring borough has operated a similar scheme successfully. ← Third paragraph: proposed solution, showing awareness of the reader's perspective

I would welcome the opportunity to discuss this further and am happy to provide a petition from Year 9 students should this be helpful. I look forward to hearing from you at your earliest convenience. ← Closing paragraph: offer a next step, polite close

Yours sincerely, ← Sign-off: sincerely because name is known

Alex Thornton ← Full name printed clearly

Notice that the letter is polite throughout, even when raising a problem. It acknowledges the reader's likely concerns (staffing costs), proposes a solution, and provides evidence (the Fairfield example). This is the standard expected in a high-quality KS3 formal letter.

Paragraphing a formal letter

A well-structured formal letter uses four to five paragraphs, each with a single purpose:

Opening paragraph: State clearly why you are writing.

Context paragraph(s): Provide the relevant background information or evidence for your point.

Development paragraph: Extend your argument, propose a solution, or explain the impact of the issue.

Closing paragraph: State what you would like to happen next and thank the reader for their time.

Each paragraph should be a maximum of five to six sentences. Long, rambling paragraphs in a formal letter suggest the writer lacks clarity of purpose.

Common mistakes at KS3

Using informal contractions. "It's," "we're," and "can't" are inappropriate in formal letters. Write "it is," "we are," and "cannot."

Confusing sincerely and faithfully. This is the single most tested convention. Memorise the rule: name = sincerely; no name = faithfully.

Not stating the purpose early enough. Some students bury the reason for writing in the second or third paragraph. Always state your purpose in the first sentence of the first paragraph.

Writing too emotionally. Even if you are writing a letter of complaint, anger and frustration are conveyed through measured language, not exclamation marks. "I was extremely disappointed to discover..." is more effective than "I cannot believe this happened!!!"

Not addressing the reader's perspective. The strongest KS3 formal letters show awareness of the recipient — their responsibilities, their constraints, and their likely concerns.

Frequently asked questions

What is the correct layout for a formal letter in KS3 English?

Your address goes in the top right corner, followed by the date written in full (for example, 16 June 2026). The recipient's name and address goes on the left, below the date. Open with "Dear [Name]," or "Dear Sir or Madam," and close with "Yours sincerely," (if you used a name) or "Yours faithfully," (if you did not). Print your full name below the sign-off. Include a brief subject line below the greeting to make your purpose immediately clear.

What is the difference between "Yours sincerely" and "Yours faithfully"?

Use "Yours sincerely" when you opened the letter with the recipient's name (for example, "Dear Mr Robinson"). Use "Yours faithfully" when you opened with "Dear Sir or Madam" because you did not know the person's name. This is one of the most commonly tested formal letter conventions in KS3 and GCSE English Language, and getting it wrong signals a lack of awareness of writing conventions.

What register should I use in a formal letter?

Formal register means using Standard English throughout: no slang, no contractions (write "cannot" not "can't"), no colloquial phrases (write "I would like to request" not "I just wanted to ask"). Use polite, precise vocabulary and complete sentences. Even if your letter is a complaint, the register must remain professional — the strength of a formal letter comes from measured language, not emotional outbursts.

How long should a KS3 formal letter be?

A KS3 formal letter should typically be four to five paragraphs and around 200 to 350 words. It is not a long piece of writing — formal letters are valued for being clear and concise, not comprehensive. Every sentence should serve a purpose: state your reason for writing, provide relevant evidence, propose a solution or next step, and close politely. Padding a formal letter with unnecessary information weakens the overall effect.

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