How to Send Large Attachments from iPhone Mail (Mail Drop)

Most email servers reject attachments above roughly 20 to 25 MB — the exact threshold depends on the recipient's provider, not Apple. When you try to send a large video, a project archive, or a high-resolution photo set from iPhone Mail and the file crosses that ceiling, iOS doesn't just fail silently. It offers an alternative: Mail Drop, a built-in iCloud feature that uploads the file to Apple's servers and drops a download link into the message body instead.

From the recipient's side, the email looks almost normal. They see a brief message with a labelled link at the bottom, click it in any browser on any device, and the file downloads straight from Apple — no iCloud account required, no special app needed. The link stays live for 30 days.

This guide covers what Mail Drop is and isn't, the step-by-step process for using it on iPhone, how it behaves across different account types and devices, what to do when the option doesn't appear, and the one limit you should warn recipients about before you rely on it for anything time-sensitive.

What you need before using Mail Drop#

Three requirements must be in place before the Mail Drop prompt can appear. The first is the one most people miss.

You need to be signed into iCloud on your iPhone. Mail Drop runs on Apple's iCloud infrastructure, so if there is no active iCloud session, there is no Mail Drop. Open Settings, tap your name at the top, and confirm you are signed into an Apple ID. If you see a 'Sign In to iPhone' prompt instead of your name, Mail Drop will not appear regardless of what else is set up.

Your iPhone must run iOS 9.2 or later. Any device capable of running iOS 14 or above clears this bar with room to spare. To check: Settings, then General, then About, then Software Version.

You must be composing from an iCloud Mail address. Mail Drop is tied to Apple-hosted mail — addresses ending in @icloud.com, @me.com, or @mac.com. If the From field shows Gmail, Outlook, Yahoo, Exchange, or any other third-party account, the Mail Drop option will not appear. The platform differences section below covers what to do instead for those account types.

How to send a large attachment from iPhone Mail#

The process is identical to sending any attachment. Mail Drop activates automatically at the point of sending, so there is nothing extra to configure in advance.

1. 1

   Open Mail and start a new message

   Tap the compose icon in the lower-right corner of Mail to open a new message. Fill in the To, Cc, and Subject fields as you normally would. Mail Drop has nothing to do with the number of recipients — you can send to one person or many.

2. 2

   Attach the file

   Tap anywhere in the message body to bring up the keyboard toolbar. Tap the arrow icon on the left of the toolbar row to reveal the full attachment bar, then choose Attach File to browse iCloud Drive, your Files app, or a connected provider — or use the photo icon to pick from your camera roll. Attach the file as you normally would. Its size does not affect this step.

3. 3

   Tap Send

   Tap the send button in the upper-right corner. If the attachment is large enough to exceed the receiving server's limit — typically 20 to 25 MB, though the threshold varies by provider — iOS pauses and shows a sheet titled 'Message Size' with two options: 'Use Mail Drop' and 'Send as Attachment.' If the file is small enough to send directly, no sheet appears and the message goes through as normal.

4. 4

   Choose 'Use Mail Drop'

   Tap 'Use Mail Drop.' iPhone Mail uploads the file to Apple's iCloud servers and replaces the raw attachment in the outgoing message with a formatted download link. The message does not send until the upload completes. A small file under 50 MB uploads in seconds on a good Wi-Fi connection; a 2 GB video may take several minutes. Keep the Mail app in the foreground while it uploads.

5. 5

   Confirm the message sent

   Once the upload finishes, the message moves to your Sent mailbox as usual. The email your recipient receives contains the same subject, body, and any inline text you wrote, plus a labelled 'Download' link near where the attachment would otherwise appear. They tap the link, a browser opens, and the file downloads from Apple's servers. The link remains active for 30 days from the send date.

Mail Drop across accounts and devices#

Mail Drop availability depends on which account you are sending from, not which device or app you are on. iPhone Mail supports Mail Drop only for iCloud-hosted accounts. If you connect Gmail or Outlook to iPhone Mail and compose from those accounts, the Mail Drop option will never appear — those providers handle large-file delivery through their own infrastructure, described in the alternatives column below.

Mac Mail behaves identically: Mail Drop is available when sending from an iCloud address, and the same 5 GB limit and 30-day expiry apply.

What to do when Mail Drop does not appear#

If you tap Send and iOS does not offer Mail Drop, work through these causes in order. Most people land on the first or second.

The From address is not iCloud Mail. Open the compose window and check the From field. If it shows Gmail, Yahoo, an Exchange address, or any address not ending in @icloud.com, @me.com, or @mac.com, Mail Drop will not appear. Tap the From field to switch to your iCloud address if you have one connected, or use a cloud storage link as an alternative.

iCloud is not signed in or is toggled off. Go to Settings, tap your name, and look at the iCloud section. If iCloud is off entirely, Mail Drop has no infrastructure to run on. Sign in with your Apple ID or turn iCloud back on, then retry sending.

The file is under the threshold. If the attachment is small enough that the destination server will accept it directly — often because you are sending to another iCloud address or a provider with a generous limit — iOS delivers it as a regular attachment without ever prompting for Mail Drop. No prompt is not an error.

A weak network connection suppressed the prompt. iOS may skip the Mail Drop offer on an unreliable connection because it cannot guarantee the upload will complete. Switch to Wi-Fi and try again.

For accounts where Mail Drop is not available at all, the practical options are: paste a sharing link from Google Drive, OneDrive, Dropbox, or iCloud Drive instead of a raw attachment; use a file-transfer service such as WeTransfer that generates a time-limited download link independently of your email provider; or use AirDrop to hand the file to another Apple device in the room and follow up with a short confirmation email.

A faster way to handle large-file emails#

Mail Drop solves the upload, but the surrounding work stays manual: composing a clear explanation of what you sent, following up when the recipient does not acknowledge the download, keeping track of which threads are waiting on a file someone still needs to retrieve. If sending large deliverables to clients, collaborators, or candidates is a regular part of your workflow, that overhead accumulates.

AI Emaily is an AI-native email client with an AI composer that drafts those context-setting messages in your voice — what the file is, what the recipient should do with it, what you need back and by when. The follow-up autopilot tracks threads where you are waiting on confirmation, so a file sitting unclaimed in someone's inbox does not disappear from your radar. We build AI Emaily. It works with Gmail, Outlook, iCloud, and other providers, so it sits alongside the Mail Drop workflow rather than replacing it. You can try it on a 7-day free trial at aiemaily.com.