How to Separate Email Recipients With Commas in Outlook

Commas as Email Address Separators Aren't the Default in Outlook

Abstract logo

In most email programs, it is common practice to separate names of email recipients with commas. However, this process doesn't work seamlessly in Outlook, but you can change the settings to let you separate your email recipients with a comma when sending email.

Instructions in this article apply to Outlook 2019, 2016, 2013, 2010; and Outlook for Office 365.

Why Comma Separators Don't Work in Outlook

If you've tried using commas to separate recipients in Outlook, you may have received a "name could not be resolved" message. This means that Outlook doesn't understand the syntax you used when typing the recipient addresses.

That's because Outlook thinks a comma separates a last name from a first name. If you enter, Mark in Outlook, Outlook interprets that recipient as Mark

However, you can tell Outlook to treat commas as separators of email addresses rather than names.

Make Outlook Allow Commas to Separate Multiple Email Recipients

To have Outlook see commas as separating multiple email recipients:

  1. Select File > Option in Outlook.

    Screenshot of opening Options in Outlook
  2. Open the Mail category and go to the Send messages section.

    Screenshot of Send messages in Outlook
  3. Put a check next to Commas can be used to separate multiple message recipients.

    Screenshot of enabling commas for recipients in Outlook
  4. Click OK.

Allow Commas to Separate Multiple Email Recipients in handles commas between recipient email addresses a little differently. It automatically recognizes a comma between email addresses as the end of you're typing of that contact.

  1. Type the email address you're sending to in the To field. At the end of the email address, type a comma.

    Screenshot of using a comma after recipient in
  2. When you type a comma after a recipient in, it first searches for that contact in your contact list. If it finds it, it will insert that contact. If it doesn't find it, it'll accept the email address you've typed and place a box around it.

    Screenshot of adding recipients using commas in
  3. Once you're done adding all recipient emails separated by commas, you can type your message and press Send to finish. is more intuitive in the use of commas between email addresses in the To field. This makes it a little easier to enter a list of addresses to send your email to.