There are three options for SMS and MMS messaging in the US and Canada: long codes, Toll-Free numbers, and short code numbers. Each one has somewhat different registration requirements and characteristics.
The table below provides an overview of the current options for sending SMS and MMS to recipients in the US and Canada.
A note about prohibited use cases
Please note, all messaging sent via Twilio must adhere to Twilio’s Messaging Policy. In addition, some use case are not permitted for US (and Canada) messaging, regardless of which type of number and registration framework you choose. These include cannabis-related use cases and third-party lead generation services. For details, see Forbidden Message Categories for SMS and MMS in the US and Canada.
Comparison of long codes, Toll-Free numbers, and short codes for US/Canada
| Long code (A2P 10DLC) |
Toll-Free | Short code | |
| Format |
+1 NNN XXX-XXXX (where NNN is a local area code). | +1 8NN XXX-XXXX where NN is two repeated digits (e.g. +1 855). | 5 or 6 digits (e.g. 12345) |
| Coverage | Can send SMS to any country, SMS guidelines allowing. | Can send SMS to any country, SMS guidelines allowing. | Can send SMS within their own country only.† |
| Voice call capable? | Yes | Yes | No |
| Registration requirements |
A2P 10DLC registration | Toll-Free Verification | Short code application |
| Registration restrictions | Requires US EIN or non-US tax ID. Upcoming "Sole Prop" solution will support US/Canada-based individuals without EIN. | Does not require tax ID or business license. See verification requirements. | Company address and website required. |
| SMS filtering profile | A2P 10DLC registration greatly reduces filtering risk. | Verification is required before sending traffic. Verification reduces risk of carrier filtering. | No carrier filtering, as long as you adhere to the use case submitted in your short code application. |
| SMS throughput | Varies based on A2P 10DLC registration "Trust Score" | 3 SMS segments per second by default, but can be increased. | 100 SMS per second by default, but can be increased. |
| MMS capable |
Yes, to US/Canada | Yes, to US/Canada | Capable of MMS with a one-time enablement fee (US only) |
| Opt-in/opt-out keywords and blocklist (e.g. STOP/START) handled by carrier outside Twilio? |
No | Yes | No |
| Opt-in/opt-out blocklist handled directly by Twilio by default? |
Yes | Yes, as well as by carrier – see Opt-out Keyword Handling: SMS Stop Filtering for Toll Free SMS | No |
| Supports Advanced Opt-Out for custom STOP/START/HELP responses and added keywords? | Yes | Yes, but not recommended – may create duplicate messages or blocklist conflicts due to separate carrier handling | Yes |
| Delivery Receipts | Carrier | Handset | Handset |
† To send short code SMS messages in both the US and Canada, you need two different short codes; one in each country.
For more details on the different types of numbers and their capabilities, please see the following resources: