When writing a business letter, you should use a conversational tone and proper formatting, and you should be brief. Plan your letter before you write by listing the main areas or subjects to be included as well as any specific incidents or details. Then determine a logical order in which to address the issues. Briefly refer to any previous correspondence or conversations in the first paragraph, then get straight to the purpose of the business letter. Clearly state any follow-up action in the final paragraph.
Tone
Use a pleasant tone, especially if the business letter contains negative action or a negative response. Indicate appreciation for how the recipient has helped you, if applicable. In the final paragraph, thank the recipient for his or her time, consideration or effort. Without being too personal, try to use a friendly, compassionate tone for business letters. If you or your company has made a mistake, be forthright in admitting fault.
To avoid the tendency to write too formally in a business letter, use contractions such as those that are commonly used in speaking. Also, include personal pronouns — such as "I," "we" and "our" — instead of more formal choices such as "the company." Be concise. For example, instead of writing "We are in receipt of your correspondence regarding ... " simply write "We received ... ." Very formal phrases are more appropriate in certain types of legal documents or correspondence than in simple business letters.
Format
Use the proper format for a business letter. Block style is the simplest. In a block-style letter, all of the parts begin at the left margin, with no indentations.
Order of Main Components
If you use letterhead stationery with your company or personal name printed at the top, you do not need to type your name and address. If you are not using letterhead, type your address at the top of the page. You should avoid using fancy stationery or colored paper for most business letters.
About three to 10 lines after your address or below the letterhead printing, type the date, and make sure to spell out the month. Four lines below the date, type the inside address. The inside address contains the recipient's full name, street address, city and postal code, with each one on a separate line. Leave one blank line between the final line of the address and the salutation. The salutation is generally in the format "Dear Mr. Smith" or "Dear Mrs. Jones" — using the recipient's actual last name instead of these examples, of course — followed by a colon.
A single blank line separates each paragraph in the letter. Type a closing, such as "Sincerely yours" or "Regards." Use a comma after the closing.
Leaving three or four blank lines for a signature, type your name. Place your job title, if desired, below your name. If you include attachments or enclosures in your business letter, type the appropriate word — "Attachment" or "Enclosure" — after a blank line below your typed name or title.
Proofreading
Check your business letter after writing it to verify that everything is correct and complete, including all dates and any monetary amounts. Proofread the letter for typographical or grammatical mistakes. Have someone else read your letter before sending it, and don't forget to sign the letter with a blue or black ink pen.