Some formatting rules to follow when typing a business letter include using a block format, using a font such as Times New Roman size 12, and using a colon following the salutation and a comma after the closing. In the block format, the letter is left justified and single spaced, except between paragraphs where it is double spaced.
Usually, the sender's address is in the letterhead. If not using letterhead, the sender's address should be placed at the top of the letter above the date. The recipient's address is the inside address. This should include the specific name of the recipient. This address is placed one line below the address of the sender or 1 inch below the date.
The closing is placed at the same vertical point as the date, and is one line after the last paragraph. The first word should be capitalized. Four lines should be placed between the closing and the sender's name, allowing space for the signature.
If there are enclosures with the letter, the word "Enclosures" should be placed one line below the closing. Some people choose to list the name of each document that is enclosed in the envelope, which may be a good idea if there are several enclosures.
Finally, the initials of the typist are usually included if the letter was not typed by the person who signs the letter.