USA : SMS Features & Restrictions

The USA has 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.

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. 13036320365 (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 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 250 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.
  
  
• T-Mobile & Sprint classify all shortcode traffic as business related traffic or A2P therefore delivery rates may be lower then other networks. T-Mobile and Sprint customers have the ability to opt out when they're signing up to avoid receiving marketing messages. Ultimately the customer needs to contact their provider and make a change to their service plan.

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
  
  
• Marketing programs on SMS enabled toll free numbers are allowed on a limited basis. Please also be aware that carriers are running higher blocking mechanisms across traffic to catch and eradicate spamming.  The monitoring is more rigorous than on short codes so customers need to ensure they have bona fide opt-ins (with MT’s to confirm that opt-in / ensure no fat fingering) If an audit is initiated by the operators, proof of opt-ins are requested.
• T-Mobile classifies all toll free traffic as business related traffic or A2P therefore delivery rates may be lower then other networks. Customers have the ability to opt out when they're signing up to avoid receiving marketing messages. Ultimately the customer needs to contact T-Mobile and make a change to their service plan.

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

*Unicode is confirmed as not supported on US Cellular, they just support ASCII.

Note: The following behavior can lead to a Toll Free Number being temporarily blocked 

• Identical content with domain of urls changing.
• Short urls (ie bit.lys)
• Redirect URL's
• Rotating toll free senderID'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 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. 

High risk marketing programs with increased potential for spam are not allowed on P2P, shared short code or toll free SMS routes. Customers may apply for a dedicated short code for these type of programs. 

List of high risk SMS programs detailed below:

• Financial offerings, loan origination and matching

  • Payday loans
  • Short-term loans
  • Auto loans
  • Mortgage loans
  • Student loans
• Debt consolidation and reduction
• Debt forgiveness
• Investment opportunities
• Affiliate lead and/or commission generation
• Credit repair programs
• Tax relief programs
• Illegal Substances (including Cannabis)
• Work from home programs
• Get rich quick schemes
• UGGS and Rayban campaigns 
• Phishing
• Fraud or scam
• Gambling/Casino/BINGO should be age gated and only promote content like events/locations/etc and NOT actual Gambling/Casino/BINGO. 
• Deceptive marketing

*AT&T is no longer allowing the above high risk marketing programs on their network at all, even via dedicated short codes.

SHAFT sex, hate, alcohol, firearms, tobacco content is strictly prohibited. Support of  Programs that provide prohibited content is subject to permanent expiration of the entire Short Code, Long Virtual Number or Toll-Free Number or the specific  Program.  Vaping or marijuana/cannabis or content relating to dispensaries falls under this prohibited content. Programs must operate according to all applicable federal and state laws and regulations.

*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).

US SMS Delivery Options

 

Links

Global SMS Features Overview (Outbound only)

Global SMS Numbers Features Overview