USA : SMS Features & Restrictions

The USA and Canada both have very specific messaging restrictions and a direct connection is necessary in order to ensure message delivery to the numerous networks. Nexmo has extremely high-quality, direct connections in order to facilitate delivery of your SMS to the USA and Canada.

Sender ID

All SMS sent to the US must originate from either a U.S. pre-approved long number or short code that is associated with your Nexmo account. Alpha sender IDs are not supported.

Content:

P2P: Using Nexmo, p2p (person-to-person) traffic may be sent using a Nexmo US (or Canadian) long virtual number. Long virtual numbers are available here if you do not already own one.

A2P: A2P (application-to-person) traffic, such as bulk notifications, should be sent to the US via short code (*Note that Sprint and T-Mobile are heavily blocking Short Code traffic) or Toll Free Number. Nexmo has a number of pre-approved use-case short codes that can be used via our US short code API's . (**Note that Nexmo US short codes cannot be used to send SMS to Canada or other countries)  If none of our pre-approved short code use-cases are appropriate we can assist you in the application process for a dedicated short code.
 

Long virtual numbers

The feature restrictions for long-virtual-number originators are as follows:

  • Limited numeric sender only --> In the “from” field you need to specify your pre-approved US virtual number in international format e.g. 18479121345 (available in the Numbers tab) . Otherwise your message will get rejected with reject code 15 Illegal Sender Address - rejected.
  • Network delivery receipts are supported (Carriers do not send handset delivery receipts). 
  • Binary and VCard are not supported.
  • Long/concatenated SMS and unicode are supported by us, but we cannot guarantee delivery across all the local carriers.
  • Euro symbol (€) and some accented characters are not supported.
  • You may send a maximum of 1 SMS per second and per virtual number in the US and Canada due to local carriers regulations. If you send messages more quickly, the message(s) will be rejected. If you require higher throughput, you can purchase more numbers and spread your traffic across your numbers. E.g. 10 numbers = 10 SMS per second.
  • Maximum of roughly 500 messages per day and per long virtual number. If this is exceeded your number will be blocked and will no longer work. Carriers will expect traffic to be bi-directional. 
  • Repetitive URL's and keywords in the SMS body of long codes will be blocked by the carriers. 

Short Codes

  • Short Code routes support handset delivery receipts, binary and unicode encoding, long/concatenated messaging on most carriers. 
  • There is no daily maximum of messages per day restriction on our short code routes and API requests will use your overall throughput allocation.

Toll Free SMS Numbers

  • Toll Free number routes support handset delivery receipts, binary and unicode encoding, long/concatenated messaging on most carriers. 
  • There is no daily maximum of messages per day restriction on our Toll Free number routes and API requests will use your overall throughput allocation.

  • You will be charged for outbound and inbound SMS.

  • A2P Traffic can be sent via Toll Free Numbers


The file attached at the bottom of this article includes a comparison between the different products offered by Nexmo to send SMS to the U.S. 

Other features/restrictions of note:

Maximum Throughput:  There is a limit of 1 SMS per second and per virtual number for SMS sent from a long virtual number in the US and Canada due to local carriers regulations. If you send messages more quickly, the message(s) will be rejected. If you require higher throughput, you can purchase more numbers and spread your traffic across your numbers. E.g. 10 numbers = 10 SMS per second.
This does not apply to messages sent from a short code or Toll-free number.

Reach to virtual numbers: While Google Voice numbers are reachable through Nexmo, we do not provide reach to other virtual number providers due to fraud prevention precautions. If you have any particular business case where you would like to be able reach virtual numbers, please contact our Support team with details about your use case.

Social Invites: According to advice received, we believe that social invites are problematic in the US if multiple human interaction steps are not involved. The individual user should be able to decide who to send, when to send, and what to say. 

AT&T do not allow SMS with content of financial offerings and SMS of this content will be blocked by their spam filter. This includes SMS related to loans, debt consolidation, investment, credit repair, tax relief and work from home programs.

*Sprint and T-mobile have a high amount of short code blocking. Because of this, Sprint and T-mobile mobile destinations are delivered via a pool of Nexmo owned long codes for our shared shortcode 2FA API.

**Nexmo's 2FA and Alerts pre-approved short code API's can reach Canada mobile phone numbers since we can identify the destination number and change the sender ID as needed (via a pool of US long codes).

 

Links:

Global SMS Features Overview (Outbound only)

Global SMS Numbers Features Overview

 

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