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Send sign-in codes through your own Twilio Messaging, Vonage, Plivo, or 2factor.in account. Hercules creates and verifies the codes. Your provider sends the messages and bills you directly. No code is required.
SMS settings with Your SMS provider selected and fields for Twilio credentials, sender, and message

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What do I need before I start?

Custom SMS providers are available on all paid Hercules plans. Your app must use Hercules Auth 2.0. Activate and fund your provider account, then complete its sender and destination-country approvals.

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How do I connect a provider?

  1. Go to Users & Access → Auth Portal → Sign-in Methods.
  2. Next to SMS one-time passcode (OTP), click Configure.
  3. Choose Your SMS provider and select your provider.
  4. Enter the settings below and click Done.
  5. Turn on SMS one-time passcode (OTP) and click Save changes.
You can configure SMS while it is off. Done closes the dialog; Save changes applies your settings.

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What information does each provider need?

Copy Account SID and Auth Token from the Twilio Console into Hercules.This connection uses Twilio Messaging, not Twilio Verify.
For Twilio, Vonage, and Plivo, also fill in these fields:
  • Send SMS from: your provider’s sending number, including country code, or a business name approved for your destination countries.
  • Message: your sign-in text with {{code}}, for example Your sign-in code is {{code}}. This is the only supported placeholder. Use wording approved by your provider.

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How do I check that sign-in works?

  1. Open your app in Preview and go to its real sign-in page.
  2. Select your country and request a code on a phone you control.
  3. Enter the code and finish signing in.
Saving settings and the Login Preview do not send test messages. Real tests are billed by your provider. Repeat for each country you support.

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Additional FAQ

Your provider bills you directly. These messages do not use Hercules Cloud credits or incur Hercules-managed SMS fees. Provider rates and other Hercules plan and usage charges still apply.
Coverage depends on your provider, sender, and destination approvals. For India, confirm DLT (telecom sender and template registration) requirements with your provider. Hercules has no separate DLT fields for Twilio, Vonage, or Plivo. The 2factor.in template field does not replace provider-side approval.
Saved credentials are encrypted and never displayed. Leave a saved credential field blank to keep its value. Switching providers keeps saved credentials. Cancel in Auth Portal discards unsaved changes.After a plan downgrade, you can still view saved settings, turn off SMS sign-in, or remove credentials.
Codes last five minutes and allow three verification attempts. Wait 60 seconds to request another code. A resend replaces the previous code.
Check your provider’s balance, credentials, sender approvals, destination permissions, and message history. Hercules does not retry failed sends or switch to Hercules SMS.Still stuck? Open Support & feedback → Create a support ticket. Include your app, provider, and attempt time in UTC, but no phone numbers, codes, or credentials. For an error, use Report this error to include its Error ID.
Open Configure, choose another provider or Hercules SMS, then click Done → Save changes and confirm the switch if prompted. Hercules SMS rates apply when you switch to it.After a plan downgrade or if settings cannot be read, use Remove saved credentials for the selected provider or Remove all saved credentials for all. Click Done → Save changes. Removing the active custom provider turns off SMS sign-in, not other sign-in methods.For loading errors, try Retry first. Save a removal before reconnecting a provider.
No. SMS OTP supports phone sign-up and sign-in only. Users cannot add, change, or remove phone numbers on existing accounts.