Why are my SMS messages not being sent?
If SMS messages aren't delivering, the cause is almost always one of four areas: the automation didn't fire, spam protection blocked the message, there's a sender or number issue, or the account has reached its monthly SMS limit.
TL;DR
Check Account → SMS logs first — did the message appear at all? If not, the trigger never fired. If it shows "failed", check the phone number format (+45XXXXXXXX), sender configuration, and spam protection rules. Check Account → SMS settings for monthly spending limits.
4 things to check
Did the SMS trigger at all?
Go to Account → SMS logs. If there's no entry for the lead or phone number, the automation or action listener never fired. Check: "Max fires per order" reached? Automation conditions match? Message disabled?
Spam protection blocked the message
Go to Campaign Settings → SMS template → Spam protection. Check: frequency limit (max SMS per lead per hour/day), blacklist/whitelist rules, unsubscribe settings, and conditional send requirements. Any of these can silently suppress sending.
Phone number or sender issue
Phone numbers must be in full E.164 format: +4512345678. Missing country prefix is a common cause of carrier rejection. Also check that your sender name/number is valid and allowed in the destination country (some regions don't allow alphanumeric senders).
Monthly spending limit reached
Go to Account → SMS settings. If you've configured a maximum monthly SMS limit and it's been reached, all SMS will be blocked until the counter resets at the start of the next month. Increase the limit or wait for the reset.
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SMS log status codes
- Delivered: carrier confirmed receipt — message reached the handset.
- Failed: carrier rejected the message — check number format and sender configuration.
- Rejected by carrier: often a regional restriction or invalid sender type.
- Invalid phone number: number doesn't match expected format or country prefix is missing.
- Blocked: Hubhus spam protection stopped the send before dispatch.
Quick checklist
- SMS logs — does an entry exist? What status?
- Automation — is "Max fires" reached?
- Template — conditional send requirement evaluated to true?
- Template spam settings — frequency/blacklist/unsubscribe blocking?
- Lead — phone number in E.164 format?
- Account → SMS settings — monthly limit not exceeded?
- Account → SMS settings — sender name valid for destination country?
Common searches
SMS not sent • SMS failed • SMS not delivered • SMS spending limit • phone number format SMS • SMS spam blocked
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