SMS FAQ - An Azure Communication Services article

Publisher

Microsoft

URL

https://learn.microsoft.com/en-us/azure/communication-services/concepts/sms/sms-faq

Published

2026-09-23

Updated

unknown

Accessed

2026-09-25

HTTP status

200

License

Microsoft Learn content; CC BY 4.0 for docs text per MicrosoftDocs repos, verify; short excerpts and locators only

Source notes citing this source

• Azure Communication Services SMS does not support text-to-911 in the US and leaves assessment of FCC text-to-911 obligations to the customer. in context
• ACS lists use cases that are ineligible for toll-free verification, including payday and other high-risk loans, gambling, cryptocurrency, debt collection, cannabis, alcohol, tobacco and firearms. in context
• US carriers enforce STOP, START and UNSTOP on US toll-free numbers and these cannot be overridden; the carrier sends its own default reply. in context
• From January 31 2024 the toll-free messaging aggregator allowed only verified toll-free numbers to send SMS; unverified and pending-verification traffic to US and Canadian numbers is blocked. in context
• Microsoft estimates ACS toll-free verification at about five to six weeks end to end, with around eight weeks when the aggregator has a high volume of applications. in context
• ACS lists T-Mobile 10DLC daily SMS caps for Standard brands by vetting score: 75-100 at 200,000; 50-74 at 40,000; 25-49 at 10,000; 1-24 at 2,000; and 2,000 for low-volume mixed. in context
• ACS supports a UCaaS (Low Volume) campaign subtype for approved UCaaS applications where each phone number is tied to a human, such as employee texting. in context
• Microsoft warns that many US carriers block SMS containing free public URL shorteners such as bit.ly and tinyurl.com and recommends a branded shortener domain. in context
• ACS describes brand vetting as producing a score from 1 to 100, with higher scores giving higher messaging throughput limits. in context
• 10DLC registration applies only to enabling SMS on a local number and is not required for voice calling on that number. in context

Cite this source record

APA

WarmTransfer. (2026, September 23). SMS FAQ - An Azure Communication Services article. WarmTransfer. https://warmtransfer.net/knowledge/sources/ms-learn-acs-sms-faq

BibTeX

@misc{warmtransfer-ms-learn-acs-sms-faq,
  title  = {SMS FAQ - An Azure Communication Services article},
  author = {{WarmTransfer}},
  year   = {2026},
  url    = {https://warmtransfer.net/knowledge/sources/ms-learn-acs-sms-faq},
  note   = {Microsoft, accessed 2026-09-25}
}