"Your Security Code Changed" on WhatsApp: What It Means
What's the meaning of the WhatsApp notice that your security code with a contact changed? WhatsApp says a changed security code is likely because you or your contact reinstalled WhatsApp, changed phones, or added or removed a paired device. It isn't an error, and the chat keeps working as before.
The notice only shows up for people who turned on security notifications, and you can check the new code yourself from the contact's info screen. Below is what the code is, why it changes, where the setting lives, and when it's worth asking the contact what happened.
What the security code is
Every end-to-end encrypted chat between you and one other person has its own security code. WhatsApp describes it as a visible version of the special keys the two of you share, shown as a QR code and a 60-digit number. It's not the keys themselves, which stay secret.
The code exists so two people can confirm that their messages and calls really are end-to-end encrypted. It's unique to each individual chat, and it lives in the contact info screen under Encryption. Group chats don't have one: the help page describes codes only for chats between you and one other person.
Why a security code changes
WhatsApp's help center gives one list of reasons. The code might change because you or your contact:
- reinstalled WhatsApp,
- changed phones, or
- added or removed a paired device.
A paired device is a linked device, such as WhatsApp Web, the desktop app or a second phone. So a code can change without anyone changing phones: by WhatsApp's list, linking or unlinking a computer is enough, and so is a reinstall on the same phone.
WhatsApp doesn't list other causes on those pages, so we won't guess at any.
Do you see the notice at all?
Only if you've turned it on. Security code notifications are a setting, and you need to enable it on each device where you want them.
| Phone | Where to turn it on |
|---|---|
| Android | More options (three vertical dots) > Settings > Account > Security notifications > Show security notifications on this device |
| iPhone | Settings (or your profile picture) > Account > Security Notifications > Show Security Notifications on This Phone |
| WhatsApp Web or desktop | Settings > Account > Security notifications > Show security notifications on this computer |
To stop seeing them, turn the same switch off. The codes change either way. The setting only decides whether WhatsApp tells you in the chat.
WhatsApp's help pages paraphrase the notice as "your security code with that contact has changed" and don't publish the exact in-chat wording, so the line on your screen may read slightly differently.
How to verify the new code
Verification is optional, and WhatsApp says it's only used to confirm that the messages and calls you send are end-to-end encrypted. To check:
- Open the chat and tap the contact's name to open their contact info.
- Tap Encryption.
- Wait for automatic verification to finish and read the result. WhatsApp says it also verifies these codes automatically through a process called key transparency.
- To check by hand, compare the QR code or the 60-digit number. If you're next to your contact, one of you scans the other's QR code. If you're apart, send them the 60-digit number through another app and ask them to compare it with the number on their screen.
You can also tap Learn more > Verify on the notice itself to open the same page. If the codes don't match, WhatsApp says you may be scanning a different contact's code or a different phone number. Otherwise, send the contact a new message and scan again.
One more detail: if you or your contact uses WhatsApp on several devices, WhatsApp says you need to verify the security code on all of your and your contact's devices. Verifying a chat also checks that both of your lists of linked devices are up to date.
When to be careful
A changed code is expected after a new phone or a reinstall, and the contact can tell you which it was. If you weren't expecting it, for example you know your contact didn't change anything, ask them in a call or another app before you send anything sensitive such as payment details. That's our advice, not a WhatsApp rule. The help center doesn't describe the notice as a warning of any specific attack, though it does say security issues can arise if you don't verify encryption codes, and that when a scanned code matches, you can be sure no one is intercepting your messages or calls.
Related changes look different. If a contact moved to a new number, that's a separate notice, covered in what happens when you change your WhatsApp number. If a message shows "Waiting for this message" after a reinstall, see what that message means.
Where Tenashi fits
For a business, this notice is a customer-trust moment. Customers who have security notifications on may see it when your side reinstalls WhatsApp, changes phones or links a device, and a sudden grey line can make a customer wonder who is on the other end.
Connecting your number to Tenashi means linking a device, which is on WhatsApp's list of reasons for a code change. So contacts with security notifications turned on may see the notice when you connect, or when you reconnect. It's worth telling your key customers beforehand. Tenashi connects only your own number, which you link yourself by scanning a QR code on your phone. For more on the linked-device side, read how to know if your WhatsApp is linked to another device, and for the wider picture see our guide to WhatsApp for business.
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FAQ
What does "your security code with this contact changed" mean on WhatsApp?
It means the code that verifies end-to-end encryption in that chat has changed. WhatsApp says this is likely because you or your contact reinstalled WhatsApp, changed phones, or added or removed a paired device. It's a notice about a code, not a sign your chat has stopped working.
Why did a security code change when my contact didn't change phones?
Adding or removing a paired device counts, so linking WhatsApp Web, the desktop app or a business workspace can change it. A reinstall counts too. WhatsApp's help pages list these three causes and none other. Ask the contact if you're unsure.
Why don't I see security code change notifications?
They're off unless you turn them on, separately on each device. On Android, go to More options > Settings > Account > Security notifications. On iPhone, go to Settings > Account > Security Notifications. The code can still change without any notice appearing.
How do I verify a security code on WhatsApp?
Open the chat, tap the contact's name, then tap Encryption. WhatsApp runs automatic verification, and you can also scan the QR code or compare the 60-digit number by hand. If either of you uses several devices, WhatsApp says to verify on all of them.
Is a changed security code dangerous?
WhatsApp describes it as likely a reinstall, new phone or device change, and says you can always verify that a contact's code is legitimate. Verification is optional. If the change surprises you, check with the contact before sharing anything sensitive.
A changed security code has a short list of official causes, and you can verify it yourself. If your business is about to link a number to a shared workspace, get started with Tenashi and warn key customers first.