Structure, tone, and conventions for letters that need to be taken seriously — whether to an institution, an official, or someone you've never met.
A formal letter follows a predictable shape for a reason: the reader should be able to find what they need — who it's from, what it's about, what's being asked — without hunting for it.
Formal letters are used when writing to someone in an official capacity: a school principal, a company, a government office, a landlord, or anyone you don't know personally. The tone is respectful and impersonal, the structure is fixed, and the language avoids contractions, slang, and casual phrasing.
This guide walks through every part of a formal letter, from the address block to the signature, with a full example, before testing your understanding with ten practice questions.
A formal letter opens with two addresses: the sender's address (top right, or top left in some formats) and the recipient's address (left-aligned, below the date). No punctuation is needed at the end of each line in modern format.
42 Willow Street
Springfield, IL 62701
15 March 2026
The Manager
Springfield Public Library
101 Main Street
Springfield, IL 62702
If you know the recipient's name, use "Dear Mr. Harrison," or "Dear Dr. Patel,". If you don't know the name, use "Dear Sir or Madam," or "To Whom It May Concern,". Always follow the salutation with a comma, not an exclamation mark.
| Situation | Salutation |
|---|---|
| Name known | Dear Mr./Ms./Dr. [Surname], |
| Name unknown | Dear Sir or Madam, |
| Department, not a person | To Whom It May Concern, |
State your purpose clearly in the first sentence. Formal letters do not build up slowly — the reader should know why they're reading within the first line.
I am writing to request an extension on the return deadline for the books I currently have on loan.
The body develops the purpose in two or three short paragraphs: context, the specific request or information, and any supporting detail. Each paragraph should cover one idea only, and the tone should stay measured even when the topic is a complaint.
End with a polite closing sentence, then a formal sign-off that matches your salutation.
| If you used | Sign off with |
|---|---|
| Dear Mr./Ms./Dr. [Name], | Yours sincerely, |
| Dear Sir or Madam, / To Whom It May Concern, | Yours faithfully, |
Follow the sign-off with your full name, and a handwritten or typed signature above it if the letter is printed.
A tenant writing to a landlord about a repair issue would use this exact structure: address block, "Dear Mr. Alvarez," a first line stating the issue directly, a short paragraph with details (what's broken, since when), a polite closing requesting a timeline, and "Yours sincerely," followed by their name. The formality signals that the request is serious and worth acting on.
Here is a complete formal letter that puts every part above into practice — the tenant writing to their landlord about the repair, laid out exactly as it should appear on the page.
123 Cedar Lane, Apt 4B
Springfield, IL 62701
15 March 2026
Mr. Daniel Alvarez
Alvarez Property Management
88 Oak Avenue
Springfield, IL 62703
Dear Mr. Alvarez,
I am writing to report a leaking pipe under the kitchen sink at my rented apartment, 123 Cedar Lane, Apt 4B.
The leak began on 10 March and has worsened over the past few days, causing water damage to the cabinet floor. I have placed a bucket underneath to catch the water, but the problem needs a plumber's attention as soon as possible.
Could you please arrange for a repair within the next few days? I am available most afternoons and can provide access to the apartment with a few hours' notice.
Thank you for your prompt attention to this matter.
Yours sincerely,
Maria Chen
Notice how each part from the sections above appears in order: address block, date, recipient's address, salutation, a direct opening line, a body that separates context from the request, a polite closing sentence, and a sign-off that matches the salutation.
A well-structured formal letter gets taken seriously faster than a rambling one — readers in official roles skim for purpose first. Mastering this structure here makes every later topic in this series, from job applications to complaint letters, far easier to write.
10 questions. Select an answer for each, then submit to see your score instantly.