Although messages sent from toll-free phone numbers can still be filtered by carriers, you can greatly reduce the likelihood of filtering by complying with rules and regulations, and following some best practices. This guide explains which SMS and MMS use cases are approved for toll-free phone numbers as well as our recommendations for ensuring high deliverability.

Approved toll-free messaging use cases

Some categories of messaging, such as high-risk financial services and third-party debt collection, are specifically forbidden on Toll-Free SMS and MMS. For more details, read our article Forbidden message categories for SMS and MMS in Canada and US.

Toll-free messaging is a great choice for transactional use cases, including the following:

• One-time password (OTP) or verification codes
• Account-related alerts or notifications
• Customer care messaging that includes some automated messaging (including satisfaction surveys)

Toll-Free SMS can also be used for promotional or marketing-type traffic. However it is extremely important to ensure that all users have opted-in and that you maintain a low opt-out ("STOP" reply) rate to avoid filtering.

Short code numbers remain the best method of sending high-volume marketing or promotional messaging across Canada and US.

Toll-free messaging best practices

Toll-Free message filtering is primarily geared toward preventing unwanted messaging, fraud, or abuse. If you are sending A2P messages that align with SIPSTACK's Acceptable Use Policy, you should generally see a low rate of filtering when using a toll-free number.

Additionally, toll-free messaging users must adhere to the following standards:

• Obtain clear opt-in from your recipients before sending them messages (the opt-in does not need to be via SMS).
• Provide easy ways for your users to opt-out of messages.
• Maintain a very low opt-out (STOP reply) rate from your recipients.
• Use shortened, branded URLs for the highest deliverability levels when sending links in the message body. Avoid using shared URL shorteners (such as popular free URL shortening services) as these can increase risk of filtering.
• Do not "load balance" by sending the same or similar message contents using multiple toll-free numbers. Carriers call this "snowshoeing" and it is specifically targeted for filtering on toll-free SMS.

Toll-free messaging verification to reduce filtering risk on compliant traffic

You can submit your business and message information for carrier verification of your toll-free SMS and MMS traffic. If your messaging traffic is compliant with all applicable rules, it greatly reduces the risk of filtering on your messaging traffic. SIPSTACK offers this verification service free of cost. Please contact SIPSTACK Support if you're interested in having your toll-free messaging service verified.

Error 30007: Toll-free SMS filtered in spite of compliance

If you suspect you may be experiencing inappropriate filtering (error 30007) on compliant outbound toll-free SMS messages despite following all best practices listed above, please contact SIPSTACK Support and we can investigate on your behalf.

When should I use toll-free SMS instead of a short code?

A short code is the ideal solution for high-volume A2P use cases. By default, short codes offer much higher messaging throughput than other types of numbers, at 100 SMS segments per second.

Toll-free phone numbers may be a better fit for certain use cases. Unlike short codes, toll-free phone numbers can be used for placing and receiving voice calls in addition to SMS messages. Toll-free SMS may also be a good choice for a business that needs A2P-type communications, but is not ready to apply for a short code.