How to increase email size limit in office 365?

Office 365 is the best cloud platform that offers many options, better email controls, and regular updates. Recently Office 365 updated some features. It also increased the maximum email size limit to 150 MB. For the last few years, the message size limit was 25 MB. With the help of this improvement, the Office 365 administrators can set the maximum message size limit from 1 MB to 150 MB.

Many people ask how to increase attachment size in Office 365, but there is no attachment size limit in Office 365. There is, however, a message size limit, which can be set. Before the update, the send or receive message size limit was 25 MB, including attachments. If you want to increase the attachment size limit in Office 365, then you need to increase the message size, not the attachment.

In this post, we will discuss how to increase the email size limit in Office 365. We will use the top two manual methods to increase the message size in office 365.

In the first method, we will use the Exchange Online admin center. In second, we will describe the PowerShell commands to increase Office 365 message size limit.

Method 1: Increase email size using the Exchange Admin Center

Sign in your Office 365 Account

Click on Admin centers and select Exchange

From the Exchange admin center, select recipients and click on Mailboxes.

Click on … icon and select Set default message size restrictions.

From the default message size restrictions popup, set Maximum size for sent message and received message and Click on OK.

Increase email size for multiple user using the Bulk Edit

Select All Mailboxes, under the Bulk Edit, select message Size Restrictions and click on update.

From the Bulk edit message size restrictions screen, set Maximum size for sent message and maximum size for received message and Click on the Save.

Method 2: Increase Office 365 attachment size limit PowerShell

This is the most preferred method. Mainly it uses by big organizations.

Phase 1: Login Office 365 account by using PowerShell


Type above command and hit the Enter key. Now, type Office 365 username and password.

Phase 2: Once you login, type the following command.

$Session=New-PSSession -ConfigurationName Microsoft.Exchange -ConnectionUri -Credential $Cred -Authentication Basic -AllowRedirection

Phase 3: Now, type the following command to import the PSSession

Import-PSSession $Session

Phase 4: You can select the below command as per your requirement.

  1. Update single mailbox

    Set-Mailbox -Identity -MaxSendSize 100MB -MaxReceiveSize 100MB

  2. Update multiple mailboxes

    (“user1”,” user 2”,” user”)|%{Set-Mailbox -Identity $_-MaxSendSize 100MB-MaxReceiveSize 100MB}

  3. Update all mailboxes

    Get-Mailbox | Set-Mailbox -MaxSendSize 100 MB -MaxReceiveSize 100 MB

  4. Update the default mailbox settings (helpful for the mailbox in the future)

    Get-MailboxPlan | Set-MailboxPlan -MaxSendSize 100MB -MaxReceiveSize 100MB

You can set all those limits using the Exchange Admin center, but it is more convenient to use PowerShell.


In this post, we discussed the manual solutions to increase the email size limit in Office 365. By using these methods, you can increase the email size limit. We hope this post will help you.

Back To Home
We use cookies on this website to enhance user experience. So by using this site you accept to such use.