This is the official API documentation for ClickSend

Below you will find a current list of the available methods for ClickSend.

NOTE: You will need to create a free account to use the API. You can register here..

Base URLs:


If you would like to use Postman click this button to download our entire API collection for instant use.

Run In Postman

Simply import our collection and create an environment with username and password variables to get started.


Basic HTTP authentication should be used in the header.

username: Your API username

password: Your API key

You can get your API credentials by clicking 'API Credentials' on the top right of the dashboard.

Authorization Header

The Authorization header is constructed as follows:

  1. Username and password are combined into a string username:password
  2. The resulting string is then encoded using Base64 encoding
  3. The authorization method and a space i.e. "Basic " is then put before the encoded string.

PHP Authentication Header Example (using cURL)

curl_setopt($ch, CURLOPT_HTTPHEADER, ['Authorization: Basic ' . base64_encode("$username:$password")]);


The API uses restful verbs.

Verb Description
GET Select one or more items. Success returns 200 status code.
POST Create a new item. Success returns 200 status code.
PUT Update an item. Success returns 200 status code.
DELETE Delete an item. Success returns 200 status code.

Status Codes

The API will respond with one of the following HTTP status codes.

Status Response Description
200 SUCCESS Request completed successfully.
201 CREATED Request has been fulfilled and has resulted in one or more new resources being created
204 NO_CONTENT the server has successfully fulfilled the request and that there is no additional content to send in the response payload body
400 BAD_REQUEST The request was invalid or cannot be otherwise served. An accompanying error message will explain further.
401 UNAUTHORIZED Authentication credentials were missing or incorrect.
403 FORBIDDEN The request is understood, but it has been refused or access is not allowed. An accompanying error message will explain why.
404 NOT_FOUND The URI requested is invalid or the resource requested does not exists.
405 METHODNOTALLOWED Method doesn't exist or is not allowed.
429 TOOMANYREQUESTS Rate Limit Exceeded. Returned when a request cannot be served due to the application’s rate limit having been exhausted for the resource. See Rate Limiting.
500 INTERNALSERVERERROR Something is broken

Application Status Codes

The following status codes can be returned in addition to the HTTP status code. For example, when using the Send SMS endpoint:

Response Description
SUCCESS Message added to queue OK. Use delivery reports to get an update on the delivery status.
MISSING_CREDENTIALS Not enough information has been supplied for authentication. Please ensure that your Username and Unique Key are supplied in your request.
ACCOUNT_NOT_ACTIVATED Your account has not been activated.
INVALID_RECIPIENT The destination mobile number is invalid.
THROTTLED Identical message body recently sent to the same recipient. Please try again in a few seconds.
INVALID_SENDER_ID Invalid Sender ID. Please ensure Sender ID is no longer than 11 characters (if alphanumeric), and contains no spaces.
INSUFFICIENT_CREDIT You have reached the end of your message credits. You will need to purchase more message credits.
INVALID_CREDENTIALS Your Username or Unique Key is incorrect.
COUNTRY_NOT_ENABLED This country is not enabled on your account.
ALREADY_EXISTS The resource you're trying to add already exists.
EMPTY_MESSAGE Message is empty.
TOO_MANY_RECIPIENTS Too many recipients.
MISSING_REQUIRED_FIELDS Some required fields are missing.
INVALID_SCHEDULE The schedule specified is invalid. Use a unix timestamp e.g. 1429170372.
NOT_ENOUGH_PERMISSION_TO_LIST_ID Don't have enough privilege to access or send to a list_id.
INTERNAL_ERROR Internal error.
INVALID_LANG An invalid language option has been provided.
INVALID_VOICE An invalid voice (gender) option has been provided.
SUBJECT_REQUIRED Usually happens when MMS Subject is empty.
INVALID_MEDIA_FILE Usually MMS media file is invalid file.
SOMETHING_IS_WRONG Generic Error happened.
REGISTRATION_NEEDED You are sending to recipients from a country that requires a registered Sender ID. Please visit Global Sending and follow the registration steps. You may be able to send to your own number without registering a Sender ID by including it as the only recipient.

Required Headers

You'll need to send some headers when making API calls.

Header Value
Content-type application/json


Some methods are paginated. By default, 1 page of 15 items will be returned. You can set the pagination parameters by adding ?page={page}&limit={limit} to the URL.


Parameter Type Default Value
page integer 1 The page number to return in the response.
limit integer 15 The number of results per page. Min 15, Max 100.


Attribute Type Value
total integer Total number of results available.
per_page integer Number of results returned per page.
current_page integer Current page number.
last_page integer Last page number.
next_page_url string A URL of the next page. null if not available.
prev_page_url string A URL of the previous page. null if not available.
from integer Number of the first result in current page.
to integer Number of the last result in current page.

Searching and Sorting

Most GET endpoints allow searching and sorting. Searches are not case-sensitive.


To perform a search, add q as a query parameter. For example:



To perform a sort, add order_by as a query parameter. For example:



By default, it will search using the AND operator. This can be set using operator as a query parameter. For example:



  • AND  - returns results matching  all  query fields specified
  • OR  - returns results matching  any  query fields specified




When creating your API app, specify the JavaScript (CORS) origins you'll be using. We use these origins to return the headers needed for CORS.

Date and Time

All date/timestamps will be returned in Unix time (also known as POSIX time or erroneously as Epoch time) with no leap seconds.

For example: 1435255816 (ISO 8601: 2015-06-25T18:10:16Z) More information: Wikipedia: Unix time.

There is ony one Unix time and it is created by using the UTC/GMT time zone. This means you might have convert time zones to calculate timestamps. Most programming language have libraries to help you converting time zones.

The current Unix time can be found here: Epoch Converter

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