Failed to deliver SMS is a metric that measures how many SMS messages weren’t delivered to your subscribers. It helps you understand how well your SMS campaigns are performing by showing what percentage of messages didn’t reach their intended recipients.
Common reasons why an SMS might fail to deliver include:
- Incorrect or invalid phone number: Misformatted, missing digits, or non-existent phone numbers prevent SMS messages from reaching the intended recipient.
- Carrier restrictions: Some carriers may block certain messages, such as promotional content, messages from unregistered short codes, messages including specific keywords, or those containing S.H.A.F.T. content.
- Network issues: Temporary network outages, congestion, or maintenance work may result in failed SMS delivery.
- Spam filters: Overly aggressive spam filters may mistakenly classify legitimate SMS messages as spam and prevent delivery.
- Message size limitations: While standard SMS messages are typically limited to 160 characters, some carriers restrict delivery of SMS messages that are too long or contain special characters.
Tips to reduce failed SMS delivery
To boost SMS deliverability, implement these tips:
- Track your messages: Use a marketing automation platform to review data from past SMS messages and identify potential reasons for failed delivery.
- Use double opt-in: This will ensure that the phone numbers in your database are valid and belong to subscribers willing to receive your text messages.
- Keep your SMS list up-to-date: Regularly clean, update, and validate your contact list to remove invalid or inactive phone numbers.
- Follow message size limits: Stick to the recommended 160-character limit for SMS messages. You can always use MMS for longer messages.
- Monitor network and carrier issues: Stay informed about potential network or carrier issues affecting SMS delivery and adjust your campaigns accordingly.
- Comply with SMS regulations: Familiarize yourself with the Telephone Consumer Protection Act and other SMS regulations to ensure compliance and avoid being blocked by carriers.
If you’re sending a large volume of SMS messages, use a marketing automation platform like Klaviyo. Not only will Klaviyo provide sign-up forms for obtaining phone numbers and tools to grow and manage your SMS list, but it will also route your messages through a reliable aggregator, guaranteeing that your messages reach your audience with no hiccups along the way.
Sign up for Klaviyo and use the SMS deliverability hub to track campaign performance and optimize your SMS campaigns.