GoHighLevel SMS Not Sending — Why It Happens and How to Fix It

SMS Issues Are Almost Always One of These Things

GoHighLevel SMS problems fall into a few clear categories. The good news is that each one has a specific fix. Here is how to identify which one you are dealing with and what to do about it.

Cause 1: A2P 10DLC Registration Not Completed

In the US, all business SMS sent over 10-digit long codes (10DLC) must be registered through A2P (Application-to-Person) registration. Unregistered numbers have severely restricted sending capabilities and many messages will simply not deliver.

To check: go to Settings → Phone Numbers in GoHighLevel and look at the registration status of your number. If it shows "Unregistered" or "Pending", your SMS sending will be unreliable until registration is approved. Complete the Brand and Campaign registration through GoHighLevel.

Cause 2: Contact Has Opted Out

If a contact previously replied STOP, UNSUBSCRIBE, CANCEL, END, QUIT, or ARRET to any message, they are placed on a Do Not Contact (DNC) list for SMS. GoHighLevel will not send SMS to this contact regardless of what your workflow instructs.

Check the contact record and look for the SMS opt-out status. The only way to re-enable SMS is if the contact actively opts back in by texting START or UNSTOP to your number.

Cause 3: Carrier Filtering

Mobile carriers (AT&T, Verizon, T-Mobile) filter messages that contain certain content patterns. Messages that look like bulk marketing — promotional language, certain URLs, specific phrases — may be filtered before delivery.

• Avoid shortened URLs (bit.ly, tinyurl) — use full branded URLs or your actual domain
• Avoid excessive use of capital letters and exclamation marks
• Do not include prices with dollar signs in the first message to a new contact
• Keep your first message conversational, not promotional

Cause 4: Wrong Phone Number Format

GoHighLevel requires phone numbers in E.164 format: +1 followed by the 10-digit number for US numbers. If a number is stored without the country code or with formatting characters (dashes, spaces, brackets), the SMS will fail silently.

To fix: run a bulk update on your contacts to standardise phone number formatting. GoHighLevel has a built-in phone number formatting option in the contacts settings.

Cause 5: Twilio Account Issue

If you are using a connected Twilio account rather than LC Phone, check your Twilio console for error logs. Common Twilio-specific issues include: insufficient account balance, number not SMS-enabled, geographic permissions not set, and trial account restrictions.

Cause 6: Sending Outside Permitted Hours

If you have time restrictions set on your workflows, SMS will queue and not send during restricted hours. Check your workflow settings for any time window restrictions that may be preventing sends.

If you are stuck on a GoHighLevel issue and need expert help, book a free consultation. I will diagnose the problem and tell you exactly how to fix it — no charge for the diagnosis.