> For the complete documentation index, see [llms.txt](https://docs.limephone.io/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.limephone.io/troubleshooting/verification-codes-and-virtual-numbers.md).

# Verification codes & virtual numbers

Understand why many services won't send verification codes (OTPs) to your LimePhone number — and what to do instead.

## Why codes don't arrive

Many services that use SMS or voice-call verification — banks, Facebook, Google, WhatsApp, PayPal, Uber, Airbnb, and others — detect virtual/VoIP numbers and refuse to send codes to them. Because virtual numbers are easy to obtain and can be used from multiple devices, these services treat them as too risky for account authentication.

This is a deliberate restriction **on the sender's side**. There is nothing LimePhone can enable or fix — the service simply won't deliver OTPs to a virtual number. The same applies to verification *calls*: automated 2FA calls from these services often hang up the instant a virtual number answers, which is why such calls appear to disconnect immediately.

## What to do

* Use your personal mobile number for accounts that require OTP verification, and keep your LimePhone number for business calls and texts.
* If a service offers alternative 2FA methods — an authenticator app, email codes, or hardware keys — use those instead; they're more secure than SMS anyway.

## Other virtual-number limitations to know

* **Emergency services:** VoIP numbers may not fully support emergency calling (911/999) because of location-tracking limitations.
* **Short codes:** texts sent from short codes may not reach virtual numbers — see [Message delivery issues](/troubleshooting/message-delivery-issues.md).
* **US SMS compliance:** sending SMS to US numbers requires 10DLC registration in **Settings → Trust center**; unregistered traffic is filtered by carriers.
* **KYC:** depending on the country, you may need to complete identity (KYC) verification before a number is issued — handled in **Settings → Trust center**.
* **Fair use:** high-volume calling or spam violates fair-usage policies and can lead to suspension.