Using SMS

International calling codes

Accounts in all regions can send globally using our SMS functionality.

You must use phone numbers that are prefixed by their international calling code (for example +44 for the UK).


Getting started
   » SMS sending credits
   » SMS from name
   » Shared short code and keyword
   » Long number/virtual mobile number (VMN)
   » Allowing contacts to opt out (unsubscribe)
Creating SMS contacts and address books
   » Steps to create an SMS contact or contacts
   » Steps to create an SMS address book
Editing SMS contacts and address books
Creating an SMS campaign
Sending an SMS campaign
Sending a single SMS message
SMS message length and Unicode
   » The length of an SMS message
   » Long SMS messages
   » Standard GSM character set
   » Extended GSM character set
   » Unicode (non-standard GSM)
   » Using Emoji in your SMS messages
SMS reporting
Managing replies to your SMS campaigns
   » Viewing suppressed contacts
Changing SMS settings


You can make use of our SMS functionality to send SMS campaigns to contacts or send a single SMS to a contact.

You can add and store SMS contacts separately to any email contacts, meaning you only need a mobile number for them.

Additionally, if you wish to personalise your campaigns, you have the option to store further information against your contacts.

We also provide a reporting section, plus you can manage your replies and adjust your SMS settings. This enables you to add respondents to SMS and email address books, as well as send auto-responder campaigns.

SMS functionality is accessed by mousing over the area switcher menu (it says 'Email' upon logging in) in the top left corner and selecting SMS from the menu.


Getting started

To begin with, you'll need to contact us to purchase:

You'll also need to create:

Optionally, you can also contact us to set up:

To purchase SMS sending credits or set up long/short codes and keywords, contact your dedicated account manager (if you know who it is), or fill out this request form, making sure that you specify 'Account Management' as the query type.

SMS sending credits

SMS sending credits are required before you can send any SMS campaigns or single messages.

When adding SMS to your account, you're initially given a trial with some free SMS credits to use for a limited time period, after which you'll need to contact us to buy SMS credits.

SMS from name

The SMS from name is your sending identity. If you choose an SMS from name which is a word - 'Mycompany', for example - then recipients will see your message arrive from that word (though this can depend on which country they're in).

However, recipients won't be able to directly reply to a word. If you'd like direct replies to work, then you'll need to contact us to provision a phone number to route replies through.

Your company's name will already be your default SMS from name. However, you can have more than one from name if you wish, and any newly created from name can be set as your new default.

Please note: SMS from names can be a maximum of 11 alphanumeric characters or 15 numeric characters.

To create an SMS from name:

  1. Go to Campaigns > SMS from names
  2. Click New from name
  3. Enter a name and then click Add from name

New profiles are listed under 'SMS from names', where they can be edited and deleted.


Shared short code and keyword

A short code is usually a five- or six-digit number that can send and receive SMS to and from mobile phones. There are two types of short codes: dedicated and shared.

Shared short codes are a more common and cost-effective option than having a dedicated short code, but you'll need a keyword to go along with your shared short code if you want to allow recipients to respond to you and opt in or out of your SMS campaigns or offers. The keyword is used to identify replies to your company to ensure you receive them and can reply if you wish.

For example, if your keyword was 'COMPANY', a contact could send 'COMPANY when does the sale end?' to the shared short code. You'd then see this in your 'Replies' section and could respond to it if you chose to. The keyword must always be the first word of a message as it identifies the SMS campaign that's being responded to on a shared short code.


Please note: Short code requirements and behaviour will vary depending upon the countries you're interested in dealing with.

Long number/virtual mobile number (VMN)

Alternatively, you may prefer or require a long number (a 10- to 15-digit number which is essentially a valid phone number) if you want recipients to be able to respond to you and opt in and out of your SMS campaigns or offers. Unlike short codes which are generally shared, a long number, which is also sometimes referred to as a virtual mobile number (VMN), is dedicated to you and therefore you won’t need a keyword to receive responses. However, a down side of a long number is that it is likely to come with sending restrictions, making it less suited to marketing communications than a short code.

Please note: Long number requirements and behaviour will vary depending upon the countries you're interested in dealing with.

You can still send SMS without a short code and keyword or long number. It just means you can't receive replies or opts outs (note that in most countries you're required to allow contacts to opt out of marketing SMS messages). You might want to do this in the case of a transactional SMS, for instance, which simply informs the contact of an order status and doesn't need a response.

Please note: It may take a few days to fully provision identities, short codes and keywords with mobile networks.

Allowing contacts to opt out (unsubscribe)

In most countries it's a requirement to allow contacts to opt out of marketing SMS messages.

With a short code

To opt out with a short code, contacts can reply or send a new SMS to your short code with the keyword, followed by a space, followed by a designated word, such as 'STOP'. For example, if your keyword was 'COMPANY', a contact would need to send 'COMPANY STOP' to opt out. While 'STOP' is the most common opt-out word, which we'd recommend using, there are also some other opt-out words that can be used after the keyword. The full list is:

  • END
  • QUIT
  • STOP

Contacts will only be opted out if the opt-out word follows directly after the space after the keyword, that is 'KEYWORD OPTOUTWORD'. For example, if the keyword is 'COMPANY', the contact would need to be instructed to reply with 'COMPANY STOP'. If any other characters are added before the opt-out word then the opt-out process won't work.

With a long number

Because a long number is dedicated to your company, you don't need a keyword to allow contacts to opt out. To opt out with a long number, contacts must send a new SMS to your long number with either the word 'STOP' or one of the other opt-out words above. The opt-out word must be the first word in the response from the contact in order to opt them out.

Creating SMS contacts and address books

SMS contacts and address books are created separately from your email contacts and address books.

Steps to create an SMS contact or contacts

  1. Click on Contacts in the main navigation bar to go to the 'My contacts' page
  2. Click on Add SMS contacts icon next to 'All contacts'

  3. The 'Add SMS contacts' page will display

    SMS_add_SMS_contact_page.pngAdd a phone number into the box provided using the international format, for example +44 7xxx xxxxxx. If you're adding multiple contacts, each number should be on a separate line.

    Alternatively, click Choose file to import contacts from a CSV or Excel file on your computer. Files should be no larger than 10MB. Please ensure the source column containing the phone number is assigned to the destination column 'MobileNumber', whilst you can assign five further source columns to 'Field1' up to 'Field5' which will enable you to personalise the SMS campaigns you send. You'll probably want to keep the information in any additional fields as short as possible, bearing in mind an SMS has a limit of 160 characters.
  4. Whether manually entering a contact or contacts, or importing via a file, click the relevant Upload button

Your SMS contacts will be imported and you can confirm this afterwards by checking the number of contacts in the 'All contacts' SMS address book.


Once you've created other SMS address books, they'll be listed here too.

Steps to create an SMS address book

  1. Click on Contacts in the main navigation bar to go to the 'My contacts' page
  2. Click on Add new

  3. The 'Edit SMS address book' page will display

    SMS_create_SMS_address_book.pngEnter a name for the address book; you also have the option of providing a description for it.
  4. Click Save

This will take you automatically to the 'Add SMS contacts' page. Follow the same steps as given in Steps to create an SMS contact or contacts to add contacts to your newly created SMS address book.

Editing SMS contacts and address books

To edit an SMS contact, click on an address book and then click Edit alongside the required contact.


This will take you through to the 'Edit SMS contact' page. Here you can edit the contact's phone number should you need to, as well as add up to five fields of information to the contact for SMS personalisation.

It's a good idea to ensure the information added here is as short as possible, bearing in mind an SMS has a limit of 160 characters.


Once happy, click Save.

To edit an SMS address book, click Edit alongside the required address book.


This will take you through to the 'Edit SMS address book' page where you can alter the name of the address book and the description.

Once happy, click Save.

Creating an SMS campaign

To create an SMS campaign:

  1. Click on Campaigns in the main navigation bar to go to the 'My campaigns' page
  2. Click on New campaign
  3. Give the SMS campaign a name and click Continue

  4. Enter the content of the message in the SMS campaign editor.

    SMS_edit_SMS_campaign.pngA single SMS message can be a maximum of 160 characters, or 70 characters if you're using a non-Latin alphabet/character set. You can exceed this amount, meaning your message will flow into a second SMS, as indicated by the counter at the foot of the message.

    Personalising your SMS campaign

    You can add personalisation by clicking on the personalisation icon to the right of the message box icon and selecting any one of the five fields. For instance, clicking Field 1 will add @FIELD1@ to your message and the value held against your contact for this field will be added to your message when it's sent. Please note that there's a 128 character limit for a personalisation field.
  5. Click Save when you're happy.


If you're adding personalisation that causes a message to exceed 160 characters (or 70 characters when using a non-Latin alphabet/character set), then the message will run into a second SMS message.

Please be aware - each extra SMS message equals another SMS credit deducted from your balance.

Sending an SMS campaign

To send a campaign:

  1. Click on Campaigns in the main navigation bar to go to the 'My campaigns' page
  2. Click on the Send icon next to the SMS campaign you want to send.

    SMS_my_SMS_campaign.pngThe 'Send campaign' page will display.

  3. Tick Select all to send to all of your SMS contacts, or tick the specific address book or books that you wish to send to
  4. Choose whether to send the SMS campaign immediately or schedule it using the date and time picker
  5. Click Next
  6. You're taken to the 'Confirm send' page, where the total amount of contacts that you're about to send to will be confirmed.

    SMS_confirm_SMS_send.pngClick Confirm and send.

Sending a single SMS message

To send a single SMS message to a single contact (and this contact doesn't need to already exist in an address book):

  1. Go to Contacts > Send single message

  2. The 'Send single message' page firstly confirms how many SMS send credits you have remaining

    SMS_send_single_message.pngEnter the intended recipient's number and the message you wish to send to them. Again, if you exceed 160 characters (or 70 characters if you're using a non-Latin alphabet/character set), then your message will flow into a second SMS, as indicated by the counter at the foot of the message.
  3. Once happy, click Send.

The message is sent immediately. A page will confirm the message has been sent, along with the amount of send credits you have remaining.

The contact that you've sent to will also be added to your 'All contacts' SMS address book if they didn't already exist before.

You can also send a single SMS message via our API, using the Send SMS message operation in REST and the SendSingleSmsMessage method in SOAP.

SMS message length and Unicode

The length of an SMS message

SMS messages are constructed in sections, referred to as segments. Message sends are costed and charged per segment. In most geographical locations around the world, a single SMS segment represents a maximum of 160 standard GSM characters. Spaces between words are also counted as characters. When typing your message, be aware that the longer it gets, the more it will cost.

Long SMS messages

SMS messages containing more than 160 standard GSM characters are referred to as long messages. Smartphone handsets can combine or stitch multiple SMS segments into a single message. This is referred to as a concatenated message.

When segments are stitched together, seven characters are sacrificed per segment to facilitate concatenation. Therefore, the maximum character count for long messages are:

  • 2 message segments: 153+153=306 standard GSM characters
  • 3 message segments: 153+153+153=459 standard GSM characters
  • 4 message segments: 153+153+153+153=612 standard GSM characters

Standard GSM character set

The standard GSM set contains most widely used characters in everyday language: all Latin characters (A-Z), digits (0-9), plus a few special characters such as Ö and è. For each standard GSM character typed into a message, a single character space is consumed from the SMS segment.

Extended GSM character set

In addition to standard GSM characters, certain characters from the extended GSM character set, such as € and { symbols can be used in SMS messages. The 160 segment count remains, however these characters will use additional space (x2 spaces per character).

Unicode (non-standard GSM)

Non-standard GSM characters are referred to as Unicode characters. Unicode provides a set of additional characters, including punctuation marks, mathematical symbols, technical symbols, arrows, and characters making up non-Latin alphabets such as Thai, Chinese, or Arabic script and Emojis.

While Unicode is supported in SMS messaging, be aware that its usage will affect your message length.

Introducing a single Unicode character in your message content changes the character encoding to Unicode (UCS-2) and will immediately reduce the segment character limit from 160 to 70 characters for a single message.

When messages are stitched together with Unicode characters included, three characters are sacrificed per segment. Therefore:

  • 2 message segments with Unicode: 67+67=134 characters
  • 3 message segments with Unicode: 67+67+67=201 characters
  • 4 message segments with Unicode: 67+67+67+67=268 characters

Using Emoji in your SMS messages

Emoji use is supported in SMS messaging. All Emojis are treated as Unicode characters, reducing message segments to 70 characters. Older 16-bit Emojis will count as a single character count and newer 32-bit emojis count as two characters in a message.

SMS reporting

Reporting is collected for your SMS campaigns and single sends in the Reporting section.


Campaign sends

On the 'My reports' page, your sent campaigns are listed, along with details on how many have been sent, how many have been delivered and the date and time the campaign was last sent.


Click on the campaign to go into the campaign's report.


There are five tabs into which contacts are divided and listed, depending upon the SMS report status received for them:

  • Delivered: This indicates that your message has been successfully delivered to your contact.
  • No delivery receipt: This indicates that, whilst your message has been sent and is with the contact's network, it hasn't yet been possible to deliver it to your contact's mobile phone (for instance, their phone may be switched off). It may take time to deliver the message.
  • Failed: This indicates that your message has failed to deliver. There are a number of reasons why this might happen; the number isn't correct (a digit could be out of place, etc.); the number isn't being recognised as live by mobile networks and as such is inactive; the phone is currently outside of its network's country or region without roaming enabled. Other reasons to bear in mind are that some smartphones only allow delivery of messages from known numbers, whilst older devices can have an inbox storage limit which might be at capacity. These reasons aren't explicitly provided in reporting.
  • Expired: This indicates that the time period allowed for message delivery expired, and as a result, the message wasn't delivered. A network will allow for a certain amount of time when attempting to deliver a message to a contact's phone and, whilst this will differ between networks, it will usually be somewhere between two to three days. This can happen when a phone is out of range and remains out of range, or if it is switched off for this period.
  • Deleted: This indicates that the message was deleted by the network without being delivered. It's a rare status that networks occasionally enforce.

This is real-time reporting. You can keep refreshing the report, or come back to it later, and see the statuses change as your SMS campaign continues to get delivered. You'll be able to do this for a few days, after which time networks will expire undelivered messages.

Single sends

If you send a message using the 'Send single message' page, or via the API, or via a program node, then this report lists your single sends.

It provides details on the number it was sent to, the country, the date and time it was sent, and the starting content of the message.

You can click on Preview to see the full message content.


Managing replies to your SMS campaigns

Your SMS campaign is likely to require your contacts to reply with a word or piece of information which opts them in or out of further communications.

You can access these by clicking on Replies.

All replies are listed on the 'My replies' page, displaying the contact's mobile number, the date the reply was received and the message received.


To export an Excel file of your replies, click on Export to the left and then click on Export all.

Viewing suppressed contacts

When a contact replies to opt out of your communications, they get added to your suppressed contacts list and they won't be sent any more SMS. You can access this by going to Contacts > Suppressed contacts.

Please note - any phone numbers in this list also won't get sent to via the SMS program messaging channel.


To export an Excel file of your suppressed contacts, click on Export to the left and then click on Export all.

No resubscribe option

You can't resubscribe a contact to SMS once they've opted out. Please bear this in mind if, for instance, you're testing SMS with your own phone number.

Changing SMS settings

In the main email application, you can edit the routing relating to a keyword and short code number. Access these settings by clicking the person-and-cog icon positioned in the bottom left corner of the page, selecting Account from the settings menu and then clicking on the SMS settings tab. By editing these settings you can:

  • add any respondents directly into an SMS address book
  • add any email addresses provided in a response to an email address book
  • select an auto-responder SMS campaign to be sent immediately after receiving a response

To set these up, click on Edit alongside the keyword and short code number you want to do this for.


On the 'Editing route' page, there are three dropdowns that allow you to select the SMS address book to add respondents to, the email address book to add email address responses to, and the auto-responder campaign to send (which you'll need to have created already).


Once happy, click Save.

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