Write Formal and Informal Letters
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What you will learn
- 1Distinguish between the features of formal and informal letters
- 2Write a letter using the correct format for the purpose and audience
- 3Choose appropriate tone and language for formal versus informal contexts
Mini Lesson
A letter is a written message sent from one person to another. The tone and format of a letter depend on your audience and purpose. Formal letters are used for official purposes; informal letters are written to people you know well.
Formal Letters
- Used for business, applications, complaints, or official requests.
- Begin with "Dear Mr./Ms. [Last name]:" and end with "Sincerely," or "Respectfully,"
- Use polite, professional language — no contractions, slang, or casual expressions.
- Include the sender's address, date, recipient's address, subject line, body, and signature.
Informal Letters
- Written to friends, family, or people you know personally.
- Begin with "Dear [First name]," and end with "Love," "Best wishes," or "Take care,".
- Use a warm, relaxed tone — contractions, idioms, and friendly expressions are fine.
- Structure is flexible: greeting, chatty paragraphs, and a warm closing.
Key Features to Compare
- Formal: full sentences, polite words, no slang.
- Informal: personal pronouns (I, you, we), short sentences, exclamation points acceptable.
- Both letters should have a clear purpose stated early in the body.
Words to know
formal letter
A polite, official letter written in proper language.
e.g. A letter to a town mayor is a formal letter.
informal letter
A friendly letter using everyday language.
e.g. A letter to a cousin is an informal letter.
greeting
The opening line of a letter, like "Dear Mr. Lee".
e.g. Choose a greeting that fits your audience.
closing
The polite ending of a letter before your name.
e.g. "Sincerely" is a formal closing.
audience
The person who will read your letter.
e.g. Match your tone to your audience.
tone
The feeling the writing creates, like polite or friendly.
e.g. A formal letter has a serious tone.
Tip: Before writing, ask "Who is my reader?" and "What is my purpose?" — your answers decide whether the letter is formal or informal.
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