Send and Receive SMS Messages in Inbox
What is SMS Messaging in Inbox?
SMS messaging allows businesses to send and receive text messages and images with customers directly from their shared team Inbox. Each business is assigned a dedicated local phone number, which is used for two-way communication. SMS is available to businesses with Inbox Pro in Canada and the United States.
When Inbox Pro is activated, a business is automatically assigned a local SMS number based on its physical address. In the United States, SMS messaging also requires A2P 10DLC registration to comply with telecom regulations and ensure reliable delivery. Once registered, users can send and receive nearly unlimited SMS and MMS messages through Inbox.
Why is SMS Messaging Important?
Inbox SMS messaging provides a centralized, professional way to manage customer texting. With a dedicated business number and shared team access, businesses can send updates, answer questions, and continue conversations all in one place. A2P registration ensures messages are delivered reliably, and all communication history is retained alongside other channels like email and web chat.
How to Send an SMS Message
If your business is located in the United States, you must first complete SMS registration before you can send any messages. If your business is located in Canada, you can use SMS messaging immediately:
To send your first SMS message,
- Open
Inbox Messages - Click on
Send a Messagebutton - Type in the phone number of the customer. The input field will automatically correct the phone number to match our phone number format. Ex: +1 (555) 555-5555.
- Type a message and send it.
How to Register a US-based Business for SMS Messaging
To prevent spam and other widespread SMS abuse, phone carriers in the United States now require businesses to register their phone numbers before sending SMS messages to customers (A2P 10DLC). Registration can take up to a few weeks. Once registered, users on the business account will receive a notification and then can now send messages.
To register a US-based business, go to Settings > Inbox Settings to see a new registration card. Click register now to view the form.
Fill out the form completely, and then click “Submit information”. You can also save your progress if you are unsure of some fields and return to complete the registration later.
Your business will need an EIN number, a nine-digit number the IRS uses to identify a business for tax purposes, much like a Social Security number identifies an individual business. In the US, the Internal Revenue Service (IRS) issues a CP 575 EIN Confirmation Letter to confirm the unique Employer Identification Number (EIN) issued to a new business. The EIN provided in a CP 575 letter is required to file your company’s taxes, open a business bank account, and apply for a business credit card, loan, or payroll processing. If a business does not know their EIN, they can apply for an EIN by submitting IRS Form SS-4 online.
Frequently Asked Questions (FAQs)
I don’t see SMS in Inbox Settings?
SMS is only available to businesses located in the United States or Canada. Make sure your account address is physically located in one of those two countries; otherwise, SMS will not be available.
What’s A2P 10DLC SMS registration?
US-based businesses are required to register their business before being able to send a message. Learn how, here. Registration can take a few weeks. Once registered, users on the business account will receive a notification and then can send their first message.
How long does registration take?
Once the form has been submitted, registration through third-party verification can take anywhere from one week, up to one month. A third-party agency is being used by telecom carriers in the United States to verify business registration data with government databases.
How can I ensure my application is approved?
The most common reason for a business’s application being rejected is because the information entered in the form does not match the information the IRS has for the business, associated with the EIN / Tax ID. Make sure the business information submitted matches exactly the same information associated with the EIN.
How does a business find their business registration number a.k.a. EIN / Tax ID?
An EIN is a nine-digit number the IRS uses to identify a business for tax purposes, much like a Social Security number identifies an individual business. In the US, the Internal Revenue Service (IRS) issues a CP 575 EIN Confirmation Letter to confirm the unique Employer Identification Number (EIN) issued to a new business. The EIN provided in a CP 575 letter is required to file your company’s taxes, open a business bank account, and apply for a business credit card, loan, or payroll processing. If a business does not know their EIN, they can apply for an EIN by submitting IRS Form SS-4 online.
Can sole-proprietor businesses without an EIN register for SMS?
Not at this time. We are investigating supporting this in the future, for both US- and Canada-based businesses.
The business has already registered through the Customer Voice app. Do they need to register again?
Yes, for now. In the future, we will be automatically registering businesses for both products when they fill out the form the first time. Right now, you will need to submit the form a second time, but you will see your data that was previously entered is saved for the second submission.
The business is located outside of the United States. Do they need to register?
Registration is strictly for businesses that wish to send messages to US numbers, through US telecom carriers. Some businesses may be located outside of the United States, but wish to send SMS messages to US numbers. This is not possible currently, but will be in the future.
My business is located in Canada, why can’t I send an SMS to someone in the United States?
Currently with Inbox SMS messaging, Canadian businesses can only send SMS messages to Canadian numbers. If you try to send an SMS to a US-based number, the message will be rejected by US telecom carriers because it was not sent from an A2P-registered business.
I don’t see the registration option in Inbox?
Registration is only available for US-based businesses, with Inbox Pro product active. Ensure the account has an address located in the United States.
** What phone number is used to send out messages?**
Your business is assigned an available SMS number based on your address, using the nearest available area code. The business can share this number with customers and will receive text and MMS messages sent to it. Calls cannot be received at this number at this time.
How many messages can we send to customers?
With Inbox Pro, accounts can send and receive nearly unlimited one-by-one SMS messages to customers, while noting that each carrier has some limitations on the number of messages sent and received per day. For example, up to 2,000 SMS segments and MMS can be sent per day to customers on T-Mobile.
:::