Country Summary
| Country name | United States |
|---|---|
| ISO code | US |
| Region | North America |
| Mobile country code | 310, 311, |
| Dialing code | +1 |
Guidelines
| Two-way SMS supported | Yes |
|---|---|
| Message length | 1600 characters. Sprint does not support concatenation and messages will be delivered as multiple segments. |
| Twilio MMS support | Supported |
| Sending SMS to landline numbers | Twilio will not check whether the number is a landline and will attempt to send it to our carrier for delivery. Some carriers will convert the SMS into text-to-speech messages via voice calls. |
| Compliance considerations | Twilio strongly encourages customers to review proposed use cases with qualified legal counsel to make sure that they comply with all applicable laws. The following are some general best practices:
Note: The euro symbol (€) is not supported; avoid using this character in message submission toward the United States. |
Phone Numbers & Sender ID
| Alphanumeric | Long Code | Short Code | |||||||||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Pre-registration | Dynamic | Domestic | International | ||||||||||||||||||
| Operator network capability | Not Supported | Not Supported | Supported | Not Supported | Supported | ||||||||||||||||
| Twilio supported | Not Supported | Not Supported | Supported | Not Supported | Supported | ||||||||||||||||
| Sender ID preserved | No | No | Yes | No | Yes | ||||||||||||||||
| Provisioning time | --- | --- | Requires registration | --- | 6 - 10 weeks | ||||||||||||||||
| UCS-2 support | --- | --- | --- | --- | --- | ||||||||||||||||
| Use case restrictions | --- | --- |
For additional insight into these uses cases, including limitations, and exceptions, visit: Forbidden message categories for SMS and MMS in the US and Canada | --- |
For additional insight into these uses cases, including limitations, and exceptions, visit: Forbidden message categories for SMS and MMS in the US and Canada | ||||||||||||||||
| Best practices | --- | --- | Refer to our FAQ for long code best practices. | --- | Refer to our FAQ for short code best practices. | ||||||||||||||||
| Alphanumeric - Pre-registration | |
|---|---|
| Operator network capability | Not Supported |
| Twilio supported | Not Supported |
| Sender ID preserved | No |
| Provisioning time | --- |
| UCS-2 support | --- |
| Use case restrictions | --- |
| Best practices | --- |
| Alphanumeric - Dynamic | |
|---|---|
| Operator network capability | Not Supported |
| Twilio supported | Not Supported |
| Sender ID preserved | No |
| Provisioning time | --- |
| UCS-2 support | --- |
| Use case restrictions | --- |
| Best practices | --- |
| Long Code - Domestic | |||||||||
|---|---|---|---|---|---|---|---|---|---|
| Operator network capability | Supported | ||||||||
| Twilio supported | Supported | ||||||||
| Sender ID preserved | Yes | ||||||||
| Provisioning time | Requires registration | ||||||||
| UCS-2 support | --- | ||||||||
| Use case restrictions |
For additional insight into these uses cases, including limitations, and exceptions, visit: Forbidden message categories for SMS and MMS in the US and Canada | ||||||||
| Best practices | Refer to our FAQ for long code best practices. |
| Long Code - International | |
|---|---|
| Operator network capability | Not Supported |
| Twilio supported | Not Supported |
| Sender ID preserved | No |
| Provisioning time | --- |
| UCS-2 support | --- |
| Use case restrictions | --- |
| Best practices | --- |
| Short Code | |||||||||
|---|---|---|---|---|---|---|---|---|---|
| Operator network capability | Supported | ||||||||
| Twilio supported | Supported | ||||||||
| Sender ID preserved | Yes | ||||||||
| Provisioning time | 6 - 10 weeks | ||||||||
| UCS-2 support | --- | ||||||||
| Use case restrictions |
For additional insight into these uses cases, including limitations, and exceptions, visit: Forbidden message categories for SMS and MMS in the US and Canada | ||||||||
| Best practices | Refer to our FAQ for short code best practices. |
For the benefit of all our customers, these guidelines are provided to help you comply with applicable requirements and to help ensure Twilio's platform remains compliant with global telecommunications ecosystem requirements. These guidelines represent our current understanding of common compliance requirements generally applicable to Twilio and its customers, and do not constitute legal advice. By posting these guidelines, Twilio makes no assurances regarding the legal compliance of your application built using our APIs. You are expected to understand and abide by all compliance obligations applicable to your specific application. You should check these pages regularly for updates as telecommunications ecosystem requirements continue to evolve and change, and the information below may be updated or changed without notice.