Signal Verification Code Not Received: Why It Happens and How to Fix It
If Signal never sends your verification code, the cause is almost always one of four things: a wrong number format, weak or blocked SMS reception, too many recent attempts, or a number type Signal won't text. Fix the format first, wait out any cooldown, then request the voice call option instead of SMS.
This applies to anyone registering Signal on a new phone or reinstalling the app. The catch is that Signal gives you very little feedback. The screen just sits there, and the timer counts down.
Quick answer
Check that the country code is correct and the number has no leading zero, confirm you have signal bars and SMS isn't blocked, wait for the countdown to end, then tap "Call me" for a voice code. Too many requests in a short time can lock you out for hours, so don't keep tapping resend.
Check the number format first
This is the cause we see most. Signal wants the number in international format: the country code, then the national number. Signal's registration screen has a country picker, so you usually type only the national part.
The classic mistake is the leading zero. A UK mobile written locally as 07700 900123 must be entered as +44 7700 900123. Typing +44 07700 900123 sends the request to a number that doesn't exist, and nothing arrives. The same trap catches users in Germany, France, Australia, Ireland and many other countries where the local format starts with a 0.
Some countries are the opposite. In the United States and Canada, the +1 code is followed by a ten-digit number, and nothing gets dropped: +1 415 555 0132 is entered as 415 555 0132 with +1 selected.
- UK: +44 7XXX XXXXXX (drop the 0)
- US/Canada: +1 XXX XXX XXXX
- India: +91 XXXXX XXXXX
- Germany: +49 15X XXXXXXXX (drop the 0)
- Australia: +61 4XX XXX XXX (drop the 0)
Look at the confirmation pop-up Signal shows before sending. It repeats the full number back. Read it digit by digit.
Mobile numbers, landlines and why the difference matters
Signal sends its code by SMS. A standard landline can't receive SMS, so the text goes nowhere. That's why Signal offers a "Call me" option: the voice call reads the code aloud and works on landlines.
Some landline providers do offer text-to-voice for SMS, but it's inconsistent and varies by provider. Don't count on it. If your only number is a landline, skip SMS and ask for the call straight away once the timer allows.
Prepaid SIMs and some business lines have a related problem. A SIM with no balance or an expired plan may still show signal bars but be barred from receiving texts. If you haven't topped up in months, check that first.
Phone-side causes that look like Signal problems
The text may have arrived and been swallowed. Check these:
- Airplane mode or no signal. Obvious, but real.
- Spam or unknown-sender filtering. On iPhone, Settings, then Messages, then "Filter Unknown Senders" can push the code into a separate tab. On Android, check the spam folder in Google Messages.
- Blocked numbers. If you ever blocked a short code or unknown sender, it may still be on the list.
- Dual-SIM phones. The text goes to the number you entered, which may be on the SIM slot that isn't active for messages.
- A full message inbox on older phones.
Restarting the phone fixes more of these than you'd expect. It forces the device to re-register with the network, and a stuck registration is a common reason texts never land.
How carriers treat verification texts
Signal sends codes through third-party messaging providers, and the text then passes through your carrier's filters. Carriers in many countries run spam filtering on automated messages, and delivery can be delayed or dropped, especially when you're roaming or on a small regional network. Delivery speed varies by network and time of day, and Signal doesn't publish guarantees.
Roaming deserves its own warning. If you're abroad and your home SIM is still active, texts to your home number may be delayed or blocked depending on your roaming settings. Turn on data roaming and make sure SMS roaming is allowed, or use the voice call.
Too many attempts: the lockout nobody explains
Every time you request a code, Signal's servers log it. Request several in a row and the service will rate-limit you, sometimes with a message such as "Too many attempts, try again later". The wait can run to hours. Tapping resend during that window only makes things worse.
The better move is to stop, wait several hours, then try once with the number format double-checked and your phone restarted. Switching between Wi-Fi and mobile data between attempts can also help, since a flaky connection can stall the registration request itself.
Practical example
A user in Manchester reinstalls Signal and enters +44 07911 123456. No code arrives. After four resends, the app tells them to wait. The fix: wait, re-enter as +44 7911 123456, request SMS once, and if nothing comes within a couple of minutes, use the call option. That sequence resolves most cases of this exact kind.
Virtual numbers and Signal: a candid limitation
Some people try to register Signal with a VoIP or virtual number because they don't want to share their real one. It can work, but it's unreliable. Signal and its SMS providers can't always deliver to VoIP ranges, and a code that arrives for one person may never arrive for another. Don't assume it'll work every time. If you want to try it for privacy reasons, read our guide on verifying Signal without your own phone number first, and understand that losing access to a rented number means losing the ability to re-register.
For users who want a private paid option rather than a public inbox, PVACodes offers rental numbers for many countries and apps, though availability varies. Never use free public-inbox sites for Signal. Anyone can read the code that arrives there, and anyone could register the number after you.
Similar delivery problems affect other services too. If you're stuck on a different app, the checks in our piece on Affirm verification codes not arriving follow the same logic.
Scams and mistakes to avoid
Signal will never ask you to read your registration code to anyone. Scammers know people get verification codes, and a common trick is a message from a "friend" or "support" asking you to send the six-digit code you just received. If you share it, they can register your number on their device and take over your account.
- Never share the code with anyone, including people you know. Their account may be compromised.
- Ignore texts with links claiming your Signal account needs "verification".
- If you get a code you didn't request, someone may be trying to register your number. Don't pass it on. Turn on Registration Lock with a PIN once you're in.
That PIN matters. Registration Lock stops others from registering your number even if they obtain a code, and you'll need the PIN yourself when moving to a new phone.
Frequently asked questions
How long should I wait for a Signal code?
Usually the text arrives within a minute or two. If nothing shows after the on-screen countdown finishes, don't keep waiting. Switch to the voice call option, which often succeeds when SMS fails because it uses a different delivery route.
Why does Signal say my number is invalid?
Usually the country code is wrong or the number has an extra leading zero or digit. Pick the correct country in the dropdown, enter only the national number, and read the confirmation pop-up before continuing.
Can I get a Signal code on a landline?
Yes, through the voice call option. Landlines can't receive normal SMS, so choose "Call me" when it appears and write down the digits as they're spoken. Be ready before you tap it.
Does Signal send codes to a different phone?
The code goes to the number you typed, not the device you're using. If that SIM sits in another phone, the text lands there. Put the SIM in the phone you're using, or use a call that can reach you.
Why did I get a code I never asked for?
Someone may have typed your number by mistake, or someone is attempting to register it. Don't share the code. Ignore it, and enable Registration Lock if you already use Signal.
Will reinstalling Signal fix the problem?
Not by itself. The issue is almost always the number, the carrier or rate limiting, not the app. Update the app if it's outdated, but reinstalling repeatedly just adds more code requests.
Does a VPN affect Signal verification?
It can. A VPN doesn't change where the SMS goes, but it may interfere with the registration request. If you're stuck, turn it off, retry once on your normal connection, and wait between attempts.
How long is the lockout after too many tries?
Signal doesn't publish exact durations. In practice, waiting several hours is a safe approach before trying again. Check current Signal support guidance if the app shows a specific time.
Can I use Signal without receiving a code?
No. Registering requires verifying a phone number, whether by text or call. Once registered, you can hide your number from others using Signal's privacy settings.
What to do next
Fix the number format, restart your phone, request one SMS, then take the voice call if the text doesn't show. Stop and wait if you've hit the limit. If your SIM is dead, a landline or a number you no longer control isn't going to work, and you'll need a working mobile number you can keep long-term before trying again.