How to use Send SMS (instant) in HubSpot workflows
Synchronous SMS for OTP, two-factor authentication, password resets, and critical security alerts. Sub-2-second latency with two-key bypass for transactional messages.
How to use Send SMS (instant) in workflows
Send SMS (instant) is designed for time-critical messages: one-time passwords, two-factor authentication codes, password reset links, and critical security alerts. The action sends synchronously to 46elks with sub-2-second latency. Use the queued action for anything that is not time-critical.
When to use it
- OTP and two-factor authentication codes.
- Password reset links.
- Critical security alerts to a specific user.
- Any message where a 5 to 15 second delay (queued path) is not acceptable.
Do not use Instant for marketing, reminders, or any bulk send. It has no dedup, no quiet hours, and shares the same platform floors, so it will simply stop accepting after a burst.
Input fields
Sender (required). Must match a sender configured in SMS Campaigns > Settings.
Recipient number (required). Select a contact property or static value containing the phone number.
Message (required). The SMS body. HubSpot personalization tokens work here too.
Opt-out property (required). Type the internal name of your HubSpot opt-out property, for example sms_subscription_brave. Do not use HubSpot's token picker. The action will detect a resolved token value (such as "No") and fail with a clear message. Find the internal name under Settings > Properties in HubSpot.
Transactional only (bypass opt-out) (optional, default off). When checked, the message is sent even if the recipient is on the platform opt-out list or has the opt-out property set. Only use this for OTP, password reset, 2FA, or critical security alerts.
I confirm this is a transactional message, not marketing (optional, default off). Required second confirmation. If you tick Transactional only you must also tick this checkbox. If only one is ticked, the action fails with a clear message telling you to tick both or neither.
This two-key pattern exists so a workflow builder cannot accidentally bypass opt-out. Compliance with TCPA, GDPR, and local regulations is the workflow builder's responsibility. All bypass sends are audited. The bypass flag is recorded on the message row even if the recipient was not actually opted out.
Skip unsubscribe footer (optional, default off). Check to omit the unsubscribe footer. For OTP and security alerts this is usually correct.
What the safeguards do
- Platform opt-out: on by default. Bypassed by the two-key confirmation.
- Opt-out property: on by default. Bypassed by the two-key confirmation.
- Platform abuse floors: always apply, cannot be bypassed. 5 messages per recipient per 10 minutes. 500 messages per workflow per 10 minutes.
- Dedup and quiet hours: not supported on Instant. Instant is intended for time-critical messages.
Bypassing opt-out does not disable the abuse floors. Those protect both the recipient and the platform.
Output fields
smsSent: true if the message reached 46elks, false if skipped by a safeguard.
smsStatus: possible values include sent, skipped_opted_out_platform, skipped_opted_out_property, skipped_platform_floor_recipient, skipped_platform_floor_workflow. All skip outcomes return SUCCESS to HubSpot so the workflow continues.
Where to see results
Every instant send is logged in Brave Tools under SMS Campaigns > Workflow SMS with a Bypass chip when the two-key confirmation was used. See the Workflow SMS dashboard guide.