A business letter is often used for communication. It is more formal than a personal letter. It usually consists of six parts.

The heading is made up of the return address and the date. Often a line is skipped between the address and the date. In the address, we need to observe the addressing principle in English which is different from Chinese. Sometimes, other information such as a phone number, email address or website is listed below the address and above the date. However, the address can be omitted if the address is already printed on the stationery.

The common format of date is either American (Month/day/year) or British (day/month/year). In a formal business letter, the month is written in full spelling to avoid possible confusion.

The inside address is the address of your reader. It should include the titles and names if they are available.

The salutation (also known as greeting) begins with “Dear”. If it is written to an individual, you should use that person’s courtesy title (Mr./Mrs./Ms./Miss/Professor) and last name. When the name is unknown, “Dear Sir or Madam” is often used. Sometimes, you could also address your reader by his or her job title.

The body is the main part of a letter. A line should be skipped between paragraphs and different parts of the letter.

The complimentary close is a polite closing of your letter. It could be very formal, semiformal or informal. Its degree of formality depends on your relationship with the reader.

The signature is handwritten between the complimentary close and the typed name.

英文信函是办公或商务活动中经常使用的一种沟通方式。信函的基本结构包括以下几个部分：信头（Heading）、信内地址（Inside address）、称呼（Salutation）、正文（Body）、结尾客套语（Complimentary close）、签名（Signature）。英文信函的格式多样，最主要有2种：齐头式（Block style）和缩进式（Indented style）。