You have probably seen the little padlock icon or the line “Messages and calls are end-to-end encrypted” the first time you open a chat in WhatsApp. Maybe you have wondered what it actually means, or whether it is just something apps say to sound safe.
It is a real thing, and it is one of the few truly useful privacy protections built into the phone in your pocket. This guide explains what end-to-end encryption does, what it does not do, and which of your everyday apps already use it.
By the end, you will know how to tell an encrypted chat from an unencrypted one, and why encryption alone will never be enough to keep you safe from scams.
What is end-to-end encryption?
End-to-end encryption scrambles a message on your device so that only the person you sent it to can unscramble and read it.
Think of it like a locked box with two keys: one that only your phone has, and one that only your recipient’s phone has. Nobody in between, not the app company, not your phone carrier, not someone snooping on public WiFi, has a key that opens the box.
Plain talk: end-to-end encryption
A way of scrambling a message so it can only be unscrambled by the sender and the recipient. No one else, including the company that made the app, can read the actual words.
Without this protection, a message travels across the internet in a form that a determined outsider, or the company running the servers, could potentially read. With end-to-end encryption, the message is scrambled before it ever leaves your phone and only unscrambled once it lands on the recipient’s phone.
Which apps use end-to-end encryption?
Not every app you use for messaging treats your words the same way. Here is a simple comparison of the apps older adults use most often.
| App | Encrypted by default? | What it covers |
|---|---|---|
| Yes | Chats, group chats, photos, voice notes, and calls | |
| iMessage (blue bubbles) | Yes | Chats and attachments between Apple devices |
| Signal | Yes | Every chat and call on the app |
| Facebook Messenger | Yes, for most personal chats | Personal chats and calls (rolled out from December 2023) |
| Regular SMS text (green bubbles) | No | Not encrypted at all |
| Regular phone calls | No | Not encrypted at all |
WhatsApp uses a system called the Signal Protocol, built by the nonprofit that also makes the Signal app. According to Signal’s own announcement, WhatsApp completed its rollout of full end-to-end encryption for every message and call in April 2016. It applies automatically. There is no setting to find or switch on.
Apple’s iMessage works the same way for messages sent between two Apple devices, shown as blue bubbles. According to Apple’s own security documentation, these messages are end-to-end encrypted between devices.
Signal, the app, was built from the ground up around encryption and is often recommended by security researchers because the company that runs it has almost no data to hand over even if it wanted to.
Facebook Messenger is the newest of the group to catch up. Meta announced in December 2023 that it was rolling out default end-to-end encryption for personal Messenger chats and calls, a change the company said had been years in the making.
Plain talk: blue bubble vs green bubble
On an iPhone, a blue message bubble means it was sent as iMessage to another Apple device, and it is encrypted. A green bubble means it was sent as a regular SMS text message, which is not encrypted and can be seen by your phone carrier.
What end-to-end encryption actually protects
Encryption protects the content of your conversation while it travels between devices. That is a real, valuable protection. It means:
- Someone intercepting your WiFi at a cafe cannot read your WhatsApp chat.
- The company running the app cannot hand your message text over in response to a data request, because it does not have the key to read it.
- A stranger who briefly gets access to the network your message passes through sees only scrambled data.
Try this
Open a chat with a family member in WhatsApp or Signal, tap their name at the top, and look for a line about encryption or a “security code.” That confirms the chat is protected.
What end-to-end encryption does not protect against
This is the part that matters most for avoiding scams, and it is often misunderstood.
Encryption protects the message in transit. It does nothing to check who sent it, and it does nothing to protect the message once it arrives on a screen. A scammer can send you a perfectly encrypted WhatsApp message, and encryption will not stop it, flag it, or warn you.
Here is what encryption cannot do:
- It cannot verify the sender is really who they say they are. A scammer can still create a WhatsApp account, add a fake profile photo, and message you pretending to be a grandchild or your bank.
- It cannot stop someone from screenshotting or forwarding your message once it is delivered.
- It cannot protect you if your phone itself is left open or compromised, since the message is readable the moment it is decrypted on the screen.
- It cannot hide who you are talking to or when, only what you said. Companies can often still see this surrounding information, called metadata.
- It does not apply to regular SMS text messages at all, which is exactly the channel many scammers still prefer for package delivery scams and the unpaid toll text scam.
Safety tip
Never judge a message as safe just because it arrived through an encrypted app. Encryption protects the pipe the message travels through. It says nothing about whether the person on the other end is honest.
How to tell if your chat is encrypted
You do not need to dig through settings to check. A few quick signs work across most apps.
- In WhatsApp, open any one-on-one chat. Tap the contact’s name at the top, then look for “Encryption” partway down the screen.
- On an iPhone, look at the color of the message bubble. Blue means iMessage, which is encrypted between Apple devices. Green means SMS, which is not.
- In Signal, every chat is encrypted by design, so there is nothing extra to check.
- In Messenger, look for a lock icon or the words “End-to-end encrypted” near the top of a personal chat.
If you are ever unsure whether a message from a family member is really from them, encryption will not help you decide. A better approach is agreeing on a simple check, the same idea covered in our guide on setting up a family safe word.
Say this
“Before I click on anything you send me, I’m going to call you back on the number I already have saved, just to check it’s really you.”
Does encryption matter for video calls too?
Yes, in the same way. Video calling apps that use end-to-end encryption, including WhatsApp and Signal, scramble the audio and video as it travels between devices. If you mostly use video calling to see your grandchildren, our guide on video calling your grandkids covers which apps to use and how to set them up.
Encryption on a video call protects the content of the call from outsiders. It still will not tell you whether the person calling is who their profile says they are, which matters if you ever receive an unexpected video call asking for money or personal details.
The bottom line
End-to-end encryption is a genuine, valuable protection, and it is worth knowing which of your apps use it. It keeps outsiders, and often the app companies themselves, from reading the content of your private conversations.
It is not, and was never meant to be, a defense against scams. A scammer’s message can travel through the exact same encrypted pipe as a message from your best friend. The habits that protect you from scams, checking who really sent a message, being wary of unexpected requests for money, and confirming a caller’s identity before acting, matter just as much in an encrypted chat as anywhere else. If a message asks you to click a link or verify an account, treat it the same way you would treat any unfamiliar text: with a pause, not a click.
Where to go from here
Understanding tools like encryption is one part of staying safe online. If you would like a more complete, step-by-step guide to recognizing and avoiding today’s most common scams, take a look at our book.
