The difference between SMS and MMS is simple: an SMS is a short text-only message, and an MMS is a message that carries a photo, a video, an audio clip or a group conversation. SMS travels over your carrier's phone network and works without mobile data. MMS also goes through your carrier, but it needs a data connection, which is why picture messages often fail when your data is off or when you're abroad. Below you'll see what each one means, how to tell which one your phone is sending, how RCS, iMessage and WhatsApp fit in, what they cost, and how to get MMS working again.
What is an SMS?
SMS stands for Short Message Service. It's the plain "text message" every mobile phone can send and receive, from a basic phone to the latest smartphone. You don't need an app or an internet connection.
- Text only: an SMS carries letters, numbers and symbols. No photos or videos.
- 160 characters: a standard SMS holds up to 160 characters (Verizon: Texting FAQs). Emojis and some accented or non-Latin letters use a different encoding, so fewer characters fit, usually 70. Longer texts are split into several parts, and the person may get them as one message or as several in a row.
- No mobile data: to send an SMS, your iPhone needs a cellular network connection, not data. With Wi-Fi Calling on, it can also send SMS over Wi-Fi (Apple: If you can't send or receive messages).
- Not encrypted: SMS messages aren't end-to-end encrypted (Apple: iMessage, RCS and SMS/MMS).
Because SMS needs only a phone signal, it still works when your data runs out. Many banks and apps also send security codes by SMS. More on this in does texting use data.
What is an MMS?
MMS stands for Multimedia Messaging Service. It's how your phone sends a photo, a video or an audio clip through your carrier, without iMessage, RCS or a chat app. So if you send a picture to a friend and it shows up as a regular text, that's an MMS.
- Media plus text: Verizon, for example, allows up to 1,000 characters in an MMS, on top of pictures, videos and sound clips (Verizon). The limit depends on your carrier.
- Size limits: your carrier may limit the size of photos and videos you send by SMS or MMS (Apple).
- Group texts: on iPhone, a group text with someone who doesn't use iMessage goes as a group MMS or group SMS. Group MMS lets everyone send photos and videos. Group SMS doesn't support them, and every reply arrives as a separate text (Apple: Send a group text message).
- Needs data: Apple says an iPhone needs cellular data or Wi-Fi to send an MMS (Apple). On many Android phones, carriers say mobile data has to be on (Vodafone Australia).
SMS vs MMS: the main differences
Here's the difference between SMS and MMS at a glance:
- Content: SMS is text only. MMS adds photos, videos, audio clips and links.
- Length: SMS holds 160 characters per message. MMS allows longer text, with a limit set by your carrier.
- Connection: SMS needs only a phone signal. MMS needs your carrier's data connection, and on iPhone it can also use Wi-Fi.
- Groups: group texts with photos go as MMS. A group SMS can only carry text.
- Cost: on most plans with unlimited texts, both are included. If you pay per message, MMS usually costs more.
- Privacy: neither SMS nor MMS is end-to-end encrypted. To protect your messages, see how to encrypt text messages on iPhone and Android.
Are your text messages SMS or MMS?
A plain text to one person is an SMS. It becomes an MMS when you add a photo, video or audio clip, or when you text a group with people who can't get iMessage or RCS. Some carriers also send very long texts differently. But today, many "texts" are neither SMS nor MMS: they go as iMessage or RCS over the internet. Here's how to check.
On iPhone
- Blue bubble: iMessage, sent over Wi-Fi or mobile data between Apple devices.
- Green bubble: SMS, MMS or RCS, sent through your carrier (Apple).
So the difference between SMS and MMS on iPhone isn't the bubble colour: both are green. A green bubble with a photo is an MMS (or RCS). A green bubble with only text is an SMS (or RCS).
On Android
In Google Messages, the send button shows how your message will go: by SMS, by MMS, or by Wi-Fi or mobile data for RCS chats (Google: Turn on RCS chats). Add a photo to an SMS conversation and you'll see it switch to MMS.
SMS, MMS, RCS, iMessage and WhatsApp: what's the difference?
SMS and MMS are the oldest ways to text. Three newer options now carry a lot of everyday messages:
- RCS: the newer standard that upgrades SMS and MMS in your phone's own messaging app. It sends texts, high-resolution photos and videos over Wi-Fi or mobile data, with typing indicators and read receipts (Apple). On Android, you turn it on in Google Messages > Messages settings > RCS chats (Google). On iPhone, RCS needs iOS 18 or later and a carrier that supports it (Apple).
- iMessage: Apple's own service between iPhones, iPads and Macs. It uses Wi-Fi or mobile data and is end-to-end encrypted (Apple).
- WhatsApp, Signal, Telegram and Messenger: apps that only work over the internet. They don't use your texting allowance at all, but they need Wi-Fi or data.
In short: SMS and MMS are carrier messages billed by your plan. RCS still goes through your carrier but runs on data. iMessage and chat apps run only on Wi-Fi or data. If you text a friend on Android from your iPhone, the message can go as RCS if your phones and carriers support it, and as SMS or MMS if not (Verizon).
Do SMS and MMS cost money?
It depends on your plan, not on the message itself:
- Plans with unlimited texts: SMS and MMS are usually both included. Verizon, for example, bills SMS and MMS the same way unless you're on a pay-as-you-go messaging plan (Verizon).
- Pay per message: text-only messages typically cost less than messages with pictures and videos (Verizon). Check your carrier's price list.
- Data: MMS uses your carrier's data connection. Whether that counts against your data allowance depends on your carrier.
- Abroad: roaming rules change the price. See the section on texting abroad below.
iMessage, RCS and WhatsApp don't cost anything per message. They only use data, so they're free on Wi-Fi.
Why won't my MMS send? Common causes
If plain texts work but photos don't, MMS is the problem. The usual causes:
- Mobile data is off. Turn it on, even if you're on Wi-Fi. Vodafone, for example, says mobile data needs to be on to send and receive MMS (Vodafone Australia).
- MMS is turned off on your iPhone. See the steps below.
- Your APN or MMS settings are wrong. Your phone uses an APN with MMS details (MMSC, MMS proxy and port) to reach your carrier's picture message server. Carriers publish these settings, for example O2 UK for Samsung phones (O2: Can't send and receive picture messages). Here's what an APN is and how to change it.
- The file is too big. Your carrier sets the size limit. Send a shorter video, or share it by iMessage, RCS or a chat app.
- Your plan doesn't include MMS, or a spending cap blocks it. Ask your carrier.
- You're abroad with data roaming off. Vodafone UK says you need data roaming on to send and receive picture messages abroad (Vodafone UK).
If none of this helps, restart your phone and contact your carrier. Apple also says to contact your carrier if you still can't send SMS, MMS or RCS messages (Apple).
How to turn on MMS on iPhone and Android
On iPhone
- Go to Settings > Apps > Messages (on older iOS versions, Settings > Messages).
- Turn on MMS Messaging. If you don't see it, your carrier or plan may not support it, so ask them (Apple).
- Turn on Send as Text Message too, so a message goes as SMS when iMessage isn't available (Apple).
- In Settings > Cellular, check that your line and Cellular Data are on.
On Android
- Turn on mobile data from the quick settings panel. On a Pixel, you'll find it in Settings > Network & internet > SIMs (Google Pixel Help).
- If MMS still fails, check the APN. On Samsung phones it's in Settings > Connections > Mobile networks > Access Point Names (O2). Menus vary by phone and Android version, and your carrier gives you the right values.
SMS and MMS abroad: what to expect
When you travel, SMS and MMS still go through your home carrier, so its roaming rules decide what you pay:
- SMS: works with data roaming off, as long as your line is on. Your carrier may charge for each text you send abroad.
- MMS: needs data roaming on, so it can use roaming data and may cost extra. In the EU, "Roam like at home" covers calls, SMS and data from an EU plan, but MMS and other messages with media use your mobile data (European Consumer Centre France).
- UK, US, Canadian or Australian plans: EU rules don't cover them. Check your carrier's roaming page or add-on before you go.
- iMessage, RCS and WhatsApp: use data. On Wi-Fi or a travel eSIM, they don't add roaming charges.
The easy setup: keep your home line on for SMS and security codes, turn off data roaming on it, and use a travel eSIM for data. Then send your photos by iMessage or WhatsApp instead of MMS. Read is iMessage free to use abroad and can you text with eSIM data for the full setup.
A data-only eSIM gives you mobile data for your messages, photos and maps, but no phone number. Pick the region you're travelling to:
Data-only plans for Europe, the USA and Asia · Europe eSIMs · USA eSIMs · Asia eSIMs · Going somewhere else? Find your destination
Need a local number to send regular SMS in Europe? Some plans come with one: see Europe eSIMs with a phone number.
FAQs
What does MMS mean?
MMS means Multimedia Messaging Service. It's a message sent through your carrier that contains a photo, video, audio clip or other media, often with text.
What does SMS mean?
SMS means Short Message Service. It's a regular text message of up to 160 characters, sent over your carrier's phone network without mobile data.
What is the difference between SMS and MMS?
SMS is text only and needs just a phone signal. MMS carries photos, videos, audio and group texts, and needs a data connection.
Are text messages SMS or MMS?
A text-only message is an SMS. A message with a photo, video or audio clip, or a group text, is usually an MMS. On iPhone, a blue bubble is iMessage. On Android and iPhone, a text can also go as RCS.
Does MMS use data?
Yes. MMS needs a data connection. Apple says an iPhone needs cellular data or Wi-Fi to send one, and many carriers say mobile data has to be turned on. SMS doesn't use data.
Is MMS more expensive than SMS?
On plans with unlimited texts, both are usually included. If you pay per message, an MMS usually costs more than an SMS. Abroad, MMS can also use roaming data.
Why are my texts being sent as MMS?
Your phone sends a text as MMS when you add a photo, video or audio clip, or when you text a group that includes people without iMessage or RCS.
Is iMessage SMS or MMS?
Neither. iMessage is Apple's own service and runs over Wi-Fi or mobile data. If iMessage isn't available, your iPhone can send the message as SMS or MMS instead.
Can I receive MMS on a data-only eSIM?
No. A data-only eSIM has no phone number, so it can't get SMS or MMS. Keep your home line on for those, and use iMessage or WhatsApp on the eSIM's data for photos.
