Claude Unable to Send Verification Code to this Number

Getting this error from Claude on March 15, 2026, is likely due to the “Authentication Path” instability Anthropic has been experiencing over the last 48 hours.

“Claude Unable To Send Verification Code To This Number. Try A Different Number Or Try Again Later”

While the core Claude.ai service is currently operational, the phone verification gateway is being heavily throttled to prevent spam following a major outage on March 11.

Why this is happening right now

• Carrier Filtering: Some major carriers (especially in the US and UK) are currently flagging the “short-code” SMS used by Anthropic as spam.

• Virtual/VoIP Block: Claude has recently tightened its security against Google Voice, Skype, and other virtual numbers. It now strictly requires a physical SIM card number.

• IP-Region Mismatch: If you are using a VPN, Claude will often block the verification code if your IP address doesn’t match the country code of the phone number you’ve entered.

Quick Fixes to Try

• The “Incognito” Trick: Open a fresh Incognito or Private window. This clears any “stuck” session cookies that might be triggering a false bot-flag on your account.

• Disable All VPNs/Proxies: Anthropic’s fraud detection is extremely sensitive today. Ensure you are on your local home network or mobile data without any routing tools active.

• Format Check (The “0” Rule): Ensure you haven’t included a leading 0 after the country code.

  • Correct: +91 98765 43210

  • Incorrect: +91 09876 543210

• Wait Exactly 30 Minutes: If you have clicked “Send Code” more than 3 times, your account is likely rate-limited. Do not try again for 30 minutes; every additional click during this window resets the timer.

Current Status Check

[!TIP] Alternative Login: If you have an existing Google or Apple account, try signing in via SSO (Single Sign-On) rather than creating a fresh email/phone combination. This often bypasses the initial SMS check if the account is already verified by Google/Apple.