Both the colon (:) and the semicolon (;) are used quite commonly in business writing; however, there is often a lot of confusion about  which one to use and when to use them. To avoid confusing you further, here we will just look at the main use of each.

A colon is most commonly used to introduce a list (often after 'for example', 'namely', 'i.e'. 'as follows' 'as in the  following' etc.). Look at these examples:

The quotation has been divided into the following sections: course development, tuition and pre/post-course testing.

The Human Resources Department is comprised of two sections, namely: the Personnel Department and the Training Department.

We offer several types of investment opportunities, for example: income bonds, unit trusts and foreign currency.

However, if the items in a list following the colon are long or contain commas, they ought to be separated from each other using  semicolons. This helps to make the sentence clearer and easier to read. For example:

Please send this letter to the following companies: Hon, Wang and Staunton Ltd.; Baxter-Mackenzie; and Zerox Co. Ltd.

The business writing seminar will cover three main areas: clear, concise and modern English; structure, layout and organisation of business texts; and, business writing styles.