Regardless of how well you may know someone on a personal level, when writing a business email or sending a letter as an attachment in an email, the rules of business should always apply.

Friends can be informal. They can slap each other on the back or shout out their names in a crowd. For business email, the rules are usually more formal, and letters are almost always formal. Full names or last names are more often used than first names, especially when you have not developed a relationship with someone.

When writing a business letter or email, remind yourself that you are an ambassador for your company. It's not you writing a letter personally but rather you as a representative for your organization as a whole.

Sending Letters vs. Writing Emails

In most instances, sending an email is enough. If you are contacting someone for the first time, for example, or if you are replying to an email, it's seldom necessary to attach a letter. However, there are times when it is more appropriate to write a letter and attach it to the email.

Letter attachments are generally used for more formal correspondence, while emails are for less formal, faster correspondence. A good rule of thumb is that if your correspondence is something that the recipient is likely to keep for more than a day or two, a letter attachment may be a better idea. Examples of appropriate letter attachments include:

  • Resumes.
  • Offers of employment.
  • Invitations.
  • Invoices.
  • Sales quotes.
  • Reports.

Business Letter Format Sent via Email  

In today's world, Microsoft Word format DOCX is the standard format for business letters. However, you don't need Microsoft Word to use this format since virtually all word processing apps are able to open and export documents in Word format, including Apple Pages and Google Docs.

In some cases, it is acceptable to send a business email in PDF format. For example, if you have scanned a letter with your signature, you can scan that document and attach it to your email as a PDF. Additionally, if you are sending someone a contract and do not want anyone to be able to change the text, a PDF file is appropriate. Both Apple and Windows computers can open PDF documents without installing extra software.

Writing a Business Email

Unless you have already been introduced to someone, it's usually best to use a person's last name in a first email and to sign the email with your first and last name. After your name, include your title and company name when it's relevant and any contact information you would like the person to use. If you are hoping a prospective customer will call you, for example, include your telephone number.

Opening Line/Salutation

The salutation of a business email is similar to the salutation of a business letter. If you don't know the person's name, use “To Whom it May Concern” or use the person's title, such as "Dear Office Manager." If you do know the person's name, use the full name or last name, such as "Dear Robert Jones" or "Dear Mr. Jones." Unless you have met the person before, don't use an informal greeting like "Hey" or "Hello."

Email Body

Use full sentences with proper spelling and grammar. Avoid using contractions or writing in all upper-case or lower-case letters. Keep your message brief and to the point. The opening sentence can be a greeting such as "I hope all is well." However, this is usually not necessary. The final sentence can be a simple "Thank you" or a call to action, such as "I hope to hear from you soon" or "Feel free to contact me if you have any questions."

Closing Line

When closing a business email, use "Thank you," "Best regards" or "Sincerely" followed by your full name, position, company name and contact information.

Business Letter Sent Via Email Example 1

Dear Ms. Smith,

Thank you for submitting your resume to the ABC Company for the sales representative position. Would you be available for an interview at our office on Tuesday, May 9 at 9:00 a.m.?


Thomas T. Engine
VP Sales
ABC Company
(555) 123-1234

Business Letter Sent Via Email Example 2

Hi Thomas,

I would be delighted! I will be at your office on Tuesday at 9:00 a.m.

Patty Smith

Note that in this example, the job applicant has chosen to break the formality by replying to the recipient with his first name. She has also used an exclamation mark to convey her enthusiasm. The result is a warmer message, which can be appropriate for someone applying for a sales position.

Writing a Letter Attachment

In most cases, a business letter can be based on the standard template used by your word processing app. These usually have 1-inch margins, are single spaced and use standard fonts and font sizes, such as 12-point Times New Roman. Avoid using nonstandard fonts that appear excessively causal, like Chalkboard or Comic Sans. At the same time, avoid excessively fancy fonts that resemble calligraphy.

A business letter should be dated at the top, and it should include your full name, address and phone number either at the top or bottom of the letter. Use a formal salutation to begin the letter and close it with either "Sincerely" or "Best regards."

Letter Format Example 1

Dear Ms. Smith,

Thank you for applying to the ABC Company. After careful consideration, we are pleased to offer you the position of sales executive. We would like to meet with you at your earliest convenience to discuss base salary and commission structure.

Thank you,

Thomas T. Engine
VP Sales
ABC Company

Letter Format Example 2

Dear Mr. Engine,

I am pleased to accept the position of sales executive with the ABC Company.

Best regards,
Patty Smith

Note that in this example, the job applicant has used the recipient's last name when addressing him in a letter even though she may continue addressing him by his first name in email messages. Letters are generally more formal than emails regardless of your relationship with the person to whom you are writing.

Building Relationships: From Formal to Informal 

As you develop a business relationship with someone, emails can become much less formal. For example, once you have included your full contact information at the bottom of your emails a few times, you can safely assume that your recipient has saved those details.

If you are sending a short reply to a question, you can usually skip the formalities, although full sentences with proper spelling and grammar should always be the rule.

Informal Email Example 1

Hi John,

I misplaced the quote you sent me last week. Could you send it again?


Informal Email Example 2

Hi Carol,

That's not a problem at all. Here it is (attached).


How quickly you move from formal to informal correspondence does depend on your relationship and the relationship of your companies. If you have met with the other person and used his first name, that's often a good time to move to first names in emails. If the other person is a prospective client, it's usually best to wait until he uses your first name before you use his.

Group Emails and Letters

Regardless of your relationship with one person at a company, if you are sending an email to additional people in a group email, it is usually best to use a formal style. If you are using cc (carbon copy), address only the person or people in the "To" field of your letter and not the people who are in the "cc" field.

Similarly, always use a formal business-writing style when writing a letter attachment regardless of your relationship with the person being addressed. Not only does this show your respect to the person, but letters are often considered to be written from one business to another rather than one person to another, so it shows respect for the organization as well.