In this guide · 8 sections
- 01Email attachment limits you will hit
- 02Why a sharing link is safer than an attachment
- 03How to share large files securely with OneDrive or SharePoint
- 04Google Drive: share with specific people and set expiry
- 05Receiving large files: file request links
- 06Free file transfer sites and personal data
- 07Do it yourself or get help?
- 08Frequently asked questions
Short answer
Upload the file to OneDrive, SharePoint or Google Drive and share a link limited to specific people, with an expiry date where your plan allows it. To receive files, use OneDrive's file request link. Avoid free transfer sites and 'anyone with the link' shares for anything containing personal data.
Email attachment limits you will hit
The 'attachment too large' error comes from your own mail system, the recipient's, or both. The smaller limit wins.
| Service | Default limit | What happens above it |
|---|---|---|
| Microsoft 365 (Exchange Online) | 35 MB to send, 36 MB to receive; admins can raise it up to 150 MB | Outlook blocks the attachment or the email bounces |
| Gmail and Google Workspace | 25 MB of attachments per email (Workspace admins set work limits) | Gmail replaces the file with a Google Drive link |
| Outlook.com (personal) | 25 MB per attachment | Outlook suggests sharing from OneDrive instead |
| Recipient's server | Set by their IT team | The email bounces even if your side allows it |
Microsoft's Exchange Online limits note that what you can actually send also depends on the email client. Google's Gmail attachment help says files over 25 MB are uploaded to Drive automatically. Raising your limit does not help if the recipient's server refuses large messages, so links are the more reliable fix.
Why a sharing link is safer than an attachment
An attachment is a copy you lose control of the moment you press send. It sits in the recipient's mailbox, gets forwarded, and lives on in backups. A sharing link points to one copy you still control.
- You can revoke it: stop sharing and the link stops working, even after it was forwarded.
- You can limit who opens it: links for specific people require the recipient to sign in or verify their email.
- You can set an end date: expiry removes access automatically when the job is done.
- You see who has access: the sharing panel lists everyone with access.
- Misdirected email hurts less: if you send the link to the wrong person, a specific-people link will not open for them.
Receiving large files: file request links
The other half of the problem is clients sending you large files: scans, photos, design files. Asking them to email 30 attachments in parts is slow and messy.
Microsoft's file request feature in OneDrive and SharePoint creates an upload-only link to a folder. Microsoft says people who use it can only upload; they cannot see the folder's contents, edit, delete or download files, or see who else uploaded. Each file gets a name prefix showing who sent it, and you get an email notification when something arrives.
Google Drive does not have a built-in equivalent. Common alternatives are a Google Form with a file-upload question (uploaders need a Google account) or a shared folder limited to that client. For regular intake, a CRM or client portal may be tidier; see our CRM comparison.
Free file transfer sites and personal data
Free transfer services are quick, but you have little control over where the file is stored, who can open the link, or how long it lasts. Many free tiers create links anyone can open.
Fine for
- Marketing videos and brochures meant to be public
- Photos for a printer or signage vendor
- Large files with no personal or confidential data
Avoid for
- Payroll, CPF or HR files
- NRIC copies, medical or financial records
- Customer lists and contracts
- Anything your client agreement says must stay confidential
The PDPA's Protection Obligation requires organisations to make reasonable security arrangements to protect personal data in their care; PDPC summarises it on its data protection obligations page. A link anyone can open, on a service you have no agreement with, is hard to defend as reasonable. Use your business OneDrive or Drive instead. This is general information, not legal advice.
Do it yourself or get help?
Each person can start using specific-people links today. The company-wide settings (default link type, expiry for Anyone links, external sharing limits) are admin work and are what make it stick.
Large file sharing basics
Our Microsoft 365 / Google Security Lockdown (S$590) sets sharing defaults, external sharing limits and link expiry alongside MFA and admin hardening.
Frequently asked questions
Upload the file to your business OneDrive, SharePoint or Google Drive and share it with specific people rather than anyone with the link. Add an expiry date where your plan allows, and view-only access if the recipient does not need to edit. You can revoke access at any time, which you cannot do with an attachment.
For Microsoft 365 work accounts, Microsoft says the default maximum message size is 35 MB to send and 36 MB to receive, and admins can set a custom limit up to 150 MB. Personal Outlook.com accounts allow 25 MB per attachment. The recipient's mail server may still refuse large messages, so a OneDrive link is more reliable.
Attach it as usual and Gmail automatically uploads it to Google Drive and inserts a link instead. When Gmail asks about access, share with the named recipients only. You can also upload the file to Drive first, share it with specific people, and paste the link into your email.
In OneDrive or SharePoint, create a file request link for a folder. Clients can upload files without seeing anything else in the folder and do not need a OneDrive account. Google Drive has no direct equivalent, so Google users often use a Google Form with a file upload question or a folder shared with that client only.
It depends on the file. Free transfer services are fine for files meant to be public, such as brochures or marketing videos. For personal data or confidential documents, use your business cloud storage with specific-people links and expiry, because you control who can open the file and can revoke access later.