SMS notifications help you reach a wide audience quickly, without an app or development work. You can send SMS (text) or MMS (image) messages to your audience of opted-in MSISDNs (phone numbers).

SMS uses the SMMP protocol to send to devices ( MSISDNs The mobile phone number of an individual in your Airship audience. Each MSISDN represents an individual mobile device. ) that have opted in for a specific Sender ID The alphanumeric code that your SMS messages come from — like a phone number or name. Your audience subscribes to each individual sender ID they want to receive messages from. . SMS benefits include:

  • Immediacy: Send time-sensitive notifications.

  • Reach: Contact customers who don’t have your app, or re-engage customers who are inactive on other channels or at-risk.

  • Personalization: Send transactional messages triggered by a backend system, e.g., order confirmation and shipment tracking updates.

  • Mobile wallet integration: Deliver personalized passes, tickets, coupons, and more.

  • Integrated platform: Centralize all your engagement channels; manage personalization, scheduling, and deployment for all message types; and measure SMS alongside all your other channels, all in the Airship platform.

  • No app required: If you do have an app, however, SMS notifications are an additional channel that you can use to engage your audience. You can decide which channel (app, SMS, etc.) is more important for different types of messaging, adjust your messaging for different channels, set priority per channel, and much more. See Channel Coordination for details about priority channel and other cross-channel engagement strategies.

Use Cases

Sports Events

  • Before the event: Last-minute ticket offers, seat upgrades, parking coupons.
  • During the event: Coupons, promotions of venue facilities, promotion of sponsor experiences to increase partner activations.
  • Mobile wallet pass delivery: Coupons, tickets.


  • Campaigns: Location-aware promotions, promotions to drive in-store traffic, lifecycle marketing.
  • Transactional: Offer confirmations, order status updates.
  • Mobile wallet pass delivery: Loyalty card updates, coupons.


  • Day-of-travel: Flight reminders, promotions, loyalty benefits.
  • Mobile wallet pass delivery: Boarding passes, loyalty card updates, coupons.


  • Campaigns: Re-engage inactive or at-risk readers.
  • News: Preferred new categories.

Representing SMS Users (Sender and MSISDN)

A mobile device is represented by an MSISDN. An MSISDN is the mobile phone number of a device in your Airship audience. While MSISDNs represent devices, in general, you can think of an MSISDN as a person — someone in your audience.

Your messages come from one or more Sender IDs. A Sender ID is an alphanumeric code that your audience will see when they receive messages from you; it is essentially the phone number or name that your SMS messages come from. Members of your audience subscribe to each individual sender ID they want to receive messages from. Your sender ID could be a standard phone number, short code, or a set of alpha characters representing your sender, like your company name.

Each MSISDN — or member of your audience — subscribes to the sender IDs they want to receive messages from. If your project has multiple sender IDs, you should take care when sending your message to ensure that you reach the right audience members. Use the sender ID to select your audience, so you can be sure that you reach the right MSISDNs when you send your message.

SMS Notifications and Sending Methods

SMS notifications are text-based messages. They are viewed in the recipient device's native SMS client. If your message exceeds the character limitation, it will appear as successive messages to the user.

You can send SMS notifications either individually or combined with other channels. You can also send SMS notifications via Automation A set of conditions that your audience must meet before they receive a message. . Both methods are available from the dashboard and API.

MMS Notifications

You can send multi-media messages (MMS) to your SMS audience. MMS messages include a fallback, ensuring that users who can't view the original MMS message still receive a message that makes sense.

When sending an MMS message, you provide the URL for your image. If using Airship as your CDN, you can choose to upload your media rather than entering a URL.

MMS messages must be:

  • .gif, .jpeg, .jpg, or .png format.
  • Hosted over HTTP or HTTPS (for media not hosted by Airship).
  • Smaller than 2 MB (or 1 MB for .gif) — though you should use the smallest media possible to ensure that your audience receives messages quickly, regardless of connection quality.

Data & Analytics for SMS

Opt in/out counts are included in the Devices report and individual message reports. Message reports also include send counts and custom events for delivery events and errors.

These counts are also included in Performance Analytics, and you can open a Real-Time Data Streaming event stream to observe SMS-related events in real time.

SMS Configuration & Requirements

Contact Airship Support or Sales to provision your project for SMS notifications.

Your SMS channel requires a Sender ID. A Sender ID is an alphanumeric code that your audience will see when they receive messages from you; it is essentially the phone number or name that your SMS messages come from. Members of your audience subscribe to each individual sender ID they want to receive messages from. Each individual user is represented by their msisdn (phone number) registered to a particular Sender ID.

Opt-In/Out Handling

Users must opt in to receive SMS messages from your Sender ID and can opt out at any time. There are two ways users can opt in or opt out of your SMS audience:

  • Mobile-Originated (MO) Message: A message originating from the mobile handset can contain a keyword that triggers an opt-in. The opt-in keyword can trigger a single or double opt-in flow.
  • External Opt In: Users can opt in to SMS messages through your app, website, or other channel. You must register these users through the API as opted_in.

Mobile-Originated Keywords

A Mobile-originated message is a message sent from a member of your audience (originating from the mobile handset of a user) to you. A Keyword is a word that you define to perform an action, like opt-in or audience attribution, when used in a mobile-originated message. You can apply tags to your audience based on the keywords they use, segmenting your audience to send relevant messages based on your audience's keyword-indicated interests.

Contact Airship Sales to provision keywords and associated tag operations. Airship stores your keywords and associated tag operations. Custom keywords and tag operations for keywords are not available through the dashboard or API.

By default, users can text you any of these words to opt out of notifications: STOP, STOPALL, UNSUBSCRIBE, CANCEL, END, QUIT, ARRET. You can also add additional opt-out keywords; like opt-in keywords, specialized keywords can provide additional data about opt-out behaviors.

Mobile-originated messages are represented as events. Each event records the keywords that your audience uses and additional identifying information. You can use these events to observe opt-in and opt-out trends in Performance Analytics, or to get events directly from Real-Time Data Streaming.

Mobile-Originated Single Opt-In

Single opt-in is the process of registering users and considering them opted in when they send you a single message containing a keyword. This method does not require users to confirm that they want to opt in through a second mobile-originated (MO) message.

While a single opt-in is a simple way to register users, it may not always be an optimal opt-in method. Airship mobile-originated opt-in handling defaults to a double opt-in process. Contact Airship if you want to take advantage of a single opt-in workflow.

The response to the keyword is a confirmation text message that provides information about the text program. The message usually:

  • Confirms that the user has subscribed to an on-going text program.
  • Provides the number of messages the subscriber can expect to receive.
  • Informs the subscriber where they can obtain more information and how they can opt-out.
BrandX: Welcome! You will receive 5 msg/mo. No purchase required. Msg&DataRatesMayApply. To end, reply STOP. For help, reply HELP. For more info,

Mobile-Originated Double Opt-In

Double opt-in requires a user to send you a keyword indicating that they want to receive mobile messages, and a second keyword confirming their choice:

  1. Your audience texts a keyword to trigger the opt-in process.
  2. Airship sends your audience a message requesting confirmation using a keyword.
  3. Your audience texts the confirmation keyword, opting in to your audience.

Because each message in the opt-in workflow supports unique keywords, the double opt-in method provides multiple indices to categorize users as they opt in to your audience; you can add, remove, or replace tags for any of the opt-in messages, ensuring that you precisely segment your audiences and target future messages to the right users.

External Opt-In

Users can also opt in to or opt out of your SMS audience through other channels. For example, users may provide their phone number and agree to receive text messages when logged in to your website or app — through user preferences, an account profile, etc.

In these cases, it is your responsibility to ensure that your users understand when they opt in to SMS messages and provide written consent to receive SMS messages from you. You must register users who opt in outside of an SMS channel through the Airship API.

Handling Multiple Senders

Users opt in to messages from a sender. Your project can have multiple senders, and your audience can opt in to multiple senders within your project. To prevent a message from reaching the same user from multiple senders, you can select a specific sender ID in the Audience step when sending an SMS message.

If your project has multiple senders, selecting a sender ID:

  • Determines the sender that your message comes from.
  • Ensures that your message only goes to members of your audience subscribed to that sender.

SMS Data Protection and Compliance

Requests to opt in or out of SMS notifications are handled by Airship. Our opt-in and opt-out database:

  • Is segregated from campaign content.
  • Is encrypted.
  • For opt-ins and opt-outs that occurred via mobile-originated messages on Airship SMS, Airship stores date/time data for those opt-ins and opt-outs for rolling 4 years.

Inbound (MO) Message Handling

In addition to standard opt-in and opt-out operations, you can configure a webhook to respond to mobile-originated messages.

Inbound message handling uses an SMS keyword webhook. Airship forwards inbound messages from your audience to your webhook, so you can process requests from your audience and send custom, targeted responses to individual members of your audience based on the keywords they use in mobile-originated messages A message sent from a member of your audience (originating from the mobile handset of a user) to you. .

You can use a webhook to respond to mobile-originated messages when either the keyword or the information you want to respond with are variable and defined outside Airship. For example, if users want to text the defined keyword balance to your sender ID, you can use a webhook to process incoming messages and respond with each individual user's balance. If a user texts a variable keyword, like order <#orderNumber>, you can use a webhook to respond with the status of the specified order number. Talk to your Airship account manager to determine the static or variable keywords that you want to route to your webhook.

The payload Airship sends to your webhook's /inbound-sms endpoint includes a mobile_originated_id that represents an individual mobile-originated message. You will use this ID and send a response using the /sms/custom-response API. Because you are responding to a message sent to you by a member of your audience, custom responses do not require users to opt in. However, the mobile_originated_id has a 10-minute lifespan; you have 10 minutes from the time a mobile-originated message is received to issue a response, after which the mobile_originated_id expires and you will be unable to respond to the inbound message.

Your webhook must support two endpoints: * /inbound-sms (POST) - An endpoint to receive SMS inbound message payloads from Airship. * /validate (GET) - An endpoint to receive a validation object from Airship. You must respond to the validation with the Validation Code issued when you set up your webhook in Airship.

After you set up your webhook in the dashboard, you must contact your Airship account manager to determine the static or variable keywords that you want to route to your webhook.

SMS Resources