Guidelines

United States (US)

We've compiled regulatory and compliance information to help ensure you're communicating effectively and compliantly around the world.

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Locale Summary
Locale name	United States
ISO code The International Organization for Standardization two character representation for the given locale.	US
Region	North America
Mobile country code A three digit code associated with the given locale and used in conjunction with a Mobile Network Code to uniquely identify mobile networks.	310, 311
Dialing code The dialing prefix used to establish a call or send an SMS from one locale to the given locale.	+1

Guidelines
Two-way SMS supported Whether Twilio supports two-way SMS in the given locale.	Yes
Number portability available Whether number portability is available in the given locale.	Yes
Twilio concatenated message support Concatenation refers to the capability of splitting a message that is too long to be sent in one SMS into smaller pieces and then joining the pieces at the receiving end so that the receiver sees the message as one.	Yes
Message length How many characters can be sent given a particular message encoding before the message will be split into concatenated segments.	1600 characters.
Twilio MMS support Multimedia Messaging Service (MMS) provides a standards-based means to send pictures and video to mobile phones.	Supported
Sending SMS to landline numbers How Twilio handles an SMS message destined for landline telephone number.	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. This table lists some general best practices.	Twilio’s customers, including their end users and clients, must comply with applicable laws, regulations, Twilio's policies, including, but not limited, to the Twilio Acceptable Use Policy and the Twilio Messaging Policy, and industry standards, including, but not limited to, telecommunications providers’ policies. U.S. telecommunications providers may assess fees for non-compliant A2P traffic, and Twilio will pass these fees onto you. To date, T-Mobile is the first U.S. telecommunications provider to announce non-compliance fees for violations of T-Mobile’s Code of Conduct. Twilio will update these guidelines accordingly if/when additional U.S. telecommunications providers announce non-compliance fees. T-Mobile non-compliance fees are as follows: 10DLC Long Code Messaging Program Evasion: A $1,000 pass-through fee if a program/campaign is found to be using techniques such as snowshoeing, or unauthorized number replacement/recycling. Content Violation: After prior warning, a $10,000 pass-through fee may be imposed for each unique instance of content violating the T-Mobile Code of Conduct involving the same sender/content provider. This includes SHAFT (Sex, Hate, Alcohol, Firearms, Tobacco) violations, spam, phishing, and messaging that meets the Severity 0 violation as defined in the CTIA Short Code Monitoring Handbook.

Phone Numbers & Sender ID

Alphanumeric

	Pre-registration	Dynamic
Operator network capability Whether mobile operators in the given country support the feature.	Not Supported	Not Supported
Twilio supported Whether Twilio supports the feature for the given country.	Not Supported	Not Supported
Sender ID preserved In some countries sender IDs for certain sender types are not preserved and are changed for compliance and/or deliverability reasons. In these countries mobile subscribers will see a different ‘from sender ID’ than the one sent by you.	No	No
Provisioning time Provisioning is the process of getting the sender ID approved and registered with mobile networks (depending on country requirements). Provisioning time is how long this process takes in the given country.	---	---
UCS-2 support	---	---
Use case restrictions	---	---
Best practices	Note: The euro symbol (€) is not supported; avoid using this character in message submission toward the United States.	Note: The euro symbol (€) is not supported; avoid using this character in message submission toward the United States.

Long codes and short codes

	Long code domestic	Long code international	Short code
Operator network capability Whether mobile operators in the given country support the feature.	Supported	Not Supported	Supported
Twilio supported Whether Twilio supports the feature for the given country.	Supported	Not Supported	Supported
Sender ID preserved In some countries sender IDs for certain sender types are not preserved and are changed for compliance and/or deliverability reasons. In these countries mobile subscribers will see a different ‘from sender ID’ than the one sent by you.	Yes	No	Yes
Provisioning time Provisioning is the process of getting the sender ID approved and registered with mobile networks (depending on country requirements). Provisioning time is how long this process takes in the given country.	Requires registration	---	6 - 10 weeks
UCS-2 support	---	---	---
Use case restrictions	Loan Advertisements - Third Party Lenders “Get rich quick” schemes Work from Home Programs Secret Shopper Third Party Job Alerts Risk Investment Opportunities Illegal substances Lead Generation Hate Speech Dynamic Routing Snowshoeing Filter Evasion Shared Phone Numbers URL Cycling URL Redirects Number Cycling Spam Fraud or Deceptive Messaging Inapproriate Content Profanity High Risk Financial Payday Loans Short Term-High Interest Loans Third Party Mortgage Loan Student Loans Third Party Auto Loans Gambling/Sweepstakes Debt Forgiveness or Debt Collection Debt Consolidation Debt Reduction Third Party Debt Collection Credit Repair Phishing Gambling Vape Fireworks For additional insight into these uses cases, including limitations, and exceptions, visit: Forbidden message categories for SMS and MMS in the US and Canada	---	Loan Advertisements - Third Party Lenders “Get rich quick” schemes Work from Home Programs Secret Shopper Third Party Job Alerts Risk Investment Opportunities Illegal substances Lead Generation Hate Speech Dynamic Routing Snowshoeing Filter Evasion Shared Short Codes URL Cycling URL Redirects Number Cycling Spam Fraud or Deceptive Messaging Inapproriate Content Profanity High Risk Financial Payday Loans Short Term-High Interest Loans Third Party Mortgage Loan Student Loans Third Party Auto Loans Debt Forgiveness or Debt Collection Debt Consolidation Debt Reduction Third Party Debt Collection Credit Repair Phishing Gambling Vape Fireworks For additional insight into short code requirements see https://www.twilio.com/guidelines/us/short-code
Best practices	Refer to our FAQ for long code best practices. Note: The euro symbol (€) is not supported; avoid using this character in message submission toward the United States.	Note: The euro symbol (€) is not supported; avoid using this character in message submission toward the United States.	Refer to our FAQ for short code best practices. Note: The euro symbol (€) is not supported; avoid using this character in message submission toward the United States.

Toll Free

	Toll Free
Operator network capability Whether mobile operators in the given country support the feature.	Supported
Twilio supported Whether Twilio supports the feature for the given country.	Supported
Sender ID preserved In some countries sender IDs for certain sender types are not preserved and are changed for compliance and/or deliverability reasons. In these countries mobile subscribers will see a different ‘from sender ID’ than the one sent by you.	Yes
Provisioning time Provisioning is the process of getting the sender ID approved and registered with mobile networks (depending on country requirements). Provisioning time is how long this process takes in the given country.	Requires Verification
UCS-2 support	---
Use case restrictions	High-Risk Financial Services Payday Loans Short Term- High Interest Loans Auto Loans Mortgage Loans Student Loans Debt Collection Gambling/Sweepstakes Stock Alerts Cryptocurrency Get Rich Quick Schemes Deceptive Work from Home Programs Risk Investment Opportunities Multi-Level Marketing 3rd Party Debt Collection or Consolidation Debt Reduction Credit Repair Programs Lead Generation Controlled Substances Tobacco Vape Federally Illegal Drugs Pornography Profanity Hate Speech Phishing Fraud Scams Deceptive Marketing Snowshoeing Filter Evasion Fireworks 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	Note: The euro symbol (€) is not supported; avoid using this character in message submission toward the United States.

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.