除了简单书信格式和功能书信格式以外，商业书信通常由下列几个成分组成：

1. Letterhead 信头
就是信纸最上方的关于一个公司的名字和地址。

2. Dateline 日期
写信的日期。

3. Inside Address 信内地址
信内地址是收信人的地址，包括对方公司的名字和地址。

4. Salutation 称呼语
可以是 Dear Sir(s)，Ladies and Gentlemen，如果知道对方的姓名则要写对方的姓（Mr/Mrs xxx）。具体要因情况而异。

5. Body of the Letter 正文
此处就是你写信的意图和想要达成的目的了。注意商务书信要尽量简洁、直接，以免含混不清、造成误会。

6. Signature Block 签名栏
先要写上一些Complimentary Close （信尾客套语），如：Yours faithfully, Yours truly 等等。

Hand-Written Signature and Signature Identification 手写体签名和签名
签名部分包括手写体签名和印刷体签名，手写签名要在印刷的签名的上面。

以上是一封商务书信要包括的6个部分，下面是一篇例文：

Letterhead 信头 XXXXXXXX CO.
210 West Baiyun Road
Guangzhou 51201, China

Date Line日期 28 February 2006

Inside Address 信内地址 xxxxxx Co., Ltd
34 Regent Street
London, UK

Salutation称呼语 Dear Sirs:

Body of the Letter正文 We have obtained your name and address from Dee&Co. Ltd, and we are writing to inquire as to whether you would be willing to establish business relations with us.

We have been importers of shoes for many years. At present, we are interested in extending our range and would appreciate your catalogues and quotations.

If your prices are competitive we would expect to place volume orders with you.

We look forward to your early reply.

Complimentary Close客套结束语 Yours faithfully

Signature Block签名栏 (Hand-Written Signature)
Tony Smith