Building and maintaining your SMS deliverability

An SMS marketing message passes through the following phases before it reaches a customer:

1. The messaging platform: Your campaign is sent through Shopify Messaging, which applies checks for consent and content.
2. The wireless carrier: The customer's carrier decides whether to deliver, filter, or block the message. Each carrier applies its own filtering criteria, and carriers don't always disclose why a message was blocked.
3. The recipient's device: The customer's phone receives the message, as long as the device is turned on, connected, and able to receive SMS.

In addition to registering your sending number during country setup for SMS marketing, you need to ensure that you only send SMS marketing messages to customers who have consented.

Carriers treat unwanted messages as spam, so sending only to customers who clearly opted in to SMS is the most important factor in your sender reputation. Consent that customers gave for email marketing doesn't apply to SMS. Customers need to opt in to SMS specifically. Phone numbers that haven't opted in to SMS marketing are automatically excluded from your campaigns, but a low-quality list still harms your reputation. To keep your list healthy, review the following practices:

• Collect SMS consent through clear opt-in methods, such as a checkout checkbox or a keyword sign-up, rather than buying or importing lists.
• Set expectations at sign-up about the types of messages you'll send and how often.
• Remove phone numbers that consistently fail to deliver.

For the full consent and compliance requirements, refer to requirements for sending SMS marketing campaigns.

Carriers and messaging platforms scan the text of your message, any links it contains, and the page that those links lead to. Certain topics are prohibited and cause messages to be filtered or blocked. These include the categories known as SHAFT (sex, hate, alcohol, firearms, and tobacco), along with other restricted content.

To reduce the chance of filtering, review the following guidance:

• Follow the content guidelines for SMS marketing campaigns, which list the prohibited content categories in full.
• Link only to pages on your own store domain. Public link shorteners, such as bit.ly, are frequently associated with spam and are often blocked by carriers.
• Avoid all-capital words, excessive punctuation, and misspellings intended to get around filters, because these patterns are associated with spam.

Carriers monitor how customers respond to your messages. High opt-out rates and low engagement signal that your messages are unwanted, which harms your reputation. To keep customers engaged, send a consistent, reasonable volume rather than frequent bursts of messages, and use customer segments to target the right audience.

For more guidance on message structure, character counts, and quiet hours, refer to Best practices for SMS marketing campaigns.

Regularly reviewing your campaign results helps you detect delivery problems early. To review delivery metrics for a campaign, open your SMS campaigns in the Shopify Messaging app, then click the campaign that you want to review. The following metrics can help you understand your SMS deliverability:

• Delivery rate: A sudden drop can indicate carrier filtering, a content issue, or your number losing its verification status.
• Failed deliveries: Can indicate inactive numbers, landlines that can't receive SMS, or content that carriers are filtering.
• Opt-out rate: A rising opt-out rate is a sign that your frequency or content needs to change, or that your acquisition methods need review so that customers clearly understand they're opting in.

If your delivery rate drops, then reduce your sending volume, send only to your most engaged customers, and confirm that your number is verified and your content follows the content guidelines before you resume your usual volume.