MMS messaging is turned on in your phone's text settings, but it sends more data than regular SMS
MMS (Multimedia Messaging Service) is the system that lets you send photos, videos, and group texts through your regular messaging app. Unlike SMS text messages, which are text-only and use your carrier's network, MMS compresses your media files and often routes them through your carrier's data connection or the internet. Turning it on takes one or two taps, but you should understand what that means for your privacy before you do.
On most phones, MMS is either already on by default or turns on automatically the first time you try to send a photo. If you want to manually enable it, the setting lives in your messaging app's preferences, not in your phone's main settings. The exact location depends on whether you use Android or iPhone, and which messaging app you have chosen as your default.
Key Takeaways
- MMS messages are compressed and routed through your carrier's data network, which means your carrier can see what you are sending in a way they cannot with plain SMS text.
- On iPhone, MMS is on by default in the Messages app and you cannot turn it off without disabling group messaging or iMessage.
- On Android, MMS is usually on by default in your carrier's messaging app, but you can turn it off in settings if you prefer SMS-only texting.
- Turning off MMS means group texts will not work, and photo or video sends will fail unless you use a data-based app like WhatsApp or Signal instead.
- If you use a third-party messaging app like Google Messages or Samsung Messages, MMS settings are in that app's preferences, not in your phone's main settings.
How to enable MMS on iPhone
On iPhone, MMS is on by default in the Messages app and there is no separate toggle to turn it on. If you have disabled it in the past, you can re-enable it by going to Settings > Messages and making sure the toggle next to MMS Messaging is turned on (it will be green). This is the only setting you need to change.
If you have iMessage turned on (which is Apple's encrypted messaging service), MMS sits alongside it. When you send a photo or video to another iPhone user, iMessage handles it. When you send to an Android user or a group that includes Android users, MMS takes over. You cannot disable MMS on iPhone without also disabling group messaging, because group texts require MMS to work.
How to enable MMS on Android
On Android, the process depends on which messaging app you use. If you use your carrier's default app (like AT&T Messages, Verizon Messages, or T-Mobile's app), go into the app, tap the three-line menu, select Settings, then look for Advanced or Multimedia Messages. The toggle should be on. If it is off, turn it on.
If you use Google Messages (which is Google's default messaging app on many newer Android phones), open the app, tap your profile icon in the top right, select Settings, then Advanced, then Multimedia Messages. Make sure the toggle is on. Samsung Messages works the same way: open the app, tap the three dots, select Settings, then More Settings, then Multimedia Messages.
Unlike iPhone, you can disable MMS on Android without breaking group messaging. If you turn off MMS, group texts will still arrive as individual messages, and photos will fail to send unless you use a data-based app instead. Most people leave it on because the friction of switching apps is higher than the privacy cost.
What happens to your data when you send MMS
When you send an MMS message, your phone compresses the media file (usually reducing image quality) and sends it to your carrier's MMS server. Your carrier can see the metadata: who you sent it to, when, the file size, and sometimes the file type. They cannot see the content of the image itself in most cases, but they have a record that you sent media to that person at that time.
The message then travels to the recipient's carrier, which stores it temporarily before delivering it to their phone. If the recipient's phone is off or unreachable, the message sits on the carrier's server for a set period (usually 24 to 72 hours) before being deleted. During that time, the carrier has a copy of your file on their infrastructure.
This is different from iMessage on iPhone or Signal on Android, where the message is encrypted end-to-end and your carrier cannot see the content at all. It is also different from SMS, where your carrier sees only that a text message was sent, not what it contained. MMS sits in the middle: your carrier sees the transaction and has temporary custody of the file, but not the image itself.
When MMS is necessary and when you have alternatives
MMS is necessary if you want to send photos or videos through your regular messaging app to someone on a different carrier or phone type, and you do not want to use a separate app. It is also the only way group texts work on most phones. If you are texting only other iPhone users and you have iMessage on, you do not need MMS because iMessage handles it.
If you want to avoid MMS, you have two main alternatives. The first is to use a data-based messaging app like Signal, WhatsApp, or Telegram. These apps encrypt your messages end-to-end, meaning your carrier and the app company cannot see what you send. The trade-off is that the other person has to have the same app installed, and you are adding another app to your phone.
The second alternative is to send photos through email or cloud storage instead. You can email a photo to someone, or send them a link to a shared folder in Google Drive or iCloud. This takes longer and is less convenient, but it gives you more control over who can see the file and for how long.
Why your carrier wants MMS on
Your carrier profits from MMS because it uses their data network and their infrastructure. SMS is cheap for them to route — it uses almost no bandwidth. MMS uses significantly more, which means they can charge for it (though most plans include unlimited MMS now). Carriers also prefer MMS because it keeps you using their messaging system instead of switching to a third-party app like WhatsApp, which they cannot monitor or profit from.
This is why MMS is on by default on most phones. It is not a security or privacy risk in the way that malware is, but it is a data collection point. Your carrier knows you sent media to certain people at certain times, and that information can be subpoenaed by law enforcement or sold to data brokers in some jurisdictions.
Frequently Asked Questions
Will turning off MMS break my group texts?
On iPhone, you cannot turn off MMS without disabling group messaging entirely. On Android, group texts will still arrive but as individual messages instead of a thread, and you will not be able to send photos to groups. Most people leave MMS on because the convenience outweighs the privacy cost.
Can I send MMS over WiFi?
On iPhone, MMS can use WiFi if you have WiFi Calling enabled. On Android, it depends on your carrier and phone — some carriers allow MMS over WiFi, others do not. Check your carrier's settings or contact their support to confirm. If you want to send media over WiFi without using MMS, use Signal, WhatsApp, or email instead.
Does MMS work internationally?
MMS can work internationally, but your carrier may charge extra for it, and delivery is slower and less reliable than domestic MMS. If you are texting someone in another country, a data-based app like WhatsApp or Signal is faster, cheaper, and more reliable.
What is the difference between MMS and iMessage?
iMessage is Apple's encrypted messaging service that works only between Apple devices. MMS is your carrier's service that works between any phone type. If you send a photo to another iPhone user, iMessage handles it and encrypts it end-to-end. If you send to an Android user, MMS takes over and your carrier can see the transaction.
Can I use MMS if I have a prepaid phone?
Yes, MMS works on prepaid phones the same way it does on contract phones. It is on by default in your messaging app. Some prepaid carriers charge per MMS message, so check your plan before sending media. If your plan charges per message, a data-based app is cheaper.