Understanding email attachment size limits


Introduction

This article describes the maximum attachment sizes for Exchange Online and Gmail email.

Explanation

Both VT Exchange Online and VT Gmail have their own limits for attached file sizes that change based on the address of both the sender and recipient. In this article, the address is either an Internal VT address (‘@vt.edu’) or an External address (not ‘@vt.edu’). Despite the limits listed below, it is recommended to keep all email attachments limited to 25 Megabytes (MB) or smaller per email. The best practice, however, is to share the document via link from a shared drive such as Google’s shared drives, Microsoft’s SharePoint, Microsoft’s OneDrive, or something similar as attachments go against your quota. These limits cannot be adjusted.

VT Exchange Online attachment size limits

Direction

Limits (Megabytes)

Internal VT to Internal VT

150 MB

Internal VT to Internal VT (older accounts)

Varies. Less than 150 Mb. Microsoft has increased the limit over the years but has not applied this new limit to older accounts retroactively. 

External to Internal VT

35 MB

 

VT Gmail attachment size limits

Direction

Limits (Megabytes)

Internal VT to Internal VT

25 MB

External to Internal VT

50 MB