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REST API documentation

This documentation is for developers interested in using the GOV.UK Notify API to send emails, text messages or letters.

You can use it to integrate directly with the API if you cannot use one of our 6 client libraries.

Base URL

https://api.notifications.service.gov.uk

Headers

Authorisation header

The authorisation header is an API key that is encoded using JSON Web Tokens. You must include an authorisation header.

JSON Web Tokens have a standard header and a payload. The header consists of:

{
  "typ": "JWT",
  "alg": "HS256"
}

The payload consists of:

{
  "iss": "26785a09-ab16-4eb0-8407-a37497a57506",
  "iat": 1568818578
}

JSON Web Tokens are encoded using a secret key with the following format:

3d844edf-8d35-48ac-975b-e847b4f122b0

That secret key forms a part of your API key, which follows the format {key_name}-{iss-uuid}-{secret-key-uuid}.

For example, if your API key is my_test_key-26785a09-ab16-4eb0-8407-a37497a57506-3d844edf-8d35-48ac-975b-e847b4f122b0:

  • your API key name is my_test_key
  • your iss (your service id) is 26785a09-ab16-4eb0-8407-a37497a57506
  • your secret key is 3d844edf-8d35-48ac-975b-e847b4f122b0

iat (issued at) is the current time in UTC in epoch seconds. The token expires within 30 seconds of the current time.

Refer to the JSON Web Tokens website for more information on encoding your authorisation header.

When you have an encoded and signed token, add that token to a header as follows:

"Authorization": "Bearer encoded_jwt_token"

Content header

The content header is application/json:

"Content-type": "application/json"

Send a message

You can use GOV.UK Notify to send text messages, emails and letters.

Send a text message

POST /v2/notifications/sms

Request body

{
  "phone_number": "+447900900123",
  "template_id": "f33517ff-2a88-4f6e-b855-c550268ce08a"
}

Arguments

phone_number (required)

The phone number of the recipient of the text message. This can be a UK or international number.

template_id (required)

To find the template ID:

  1. Sign in to GOV.UK Notify.
  2. Go to the Templates page and select the relevant template.
  3. Select Copy template ID to clipboard.

personalisation (optional)

If a template has placeholder fields for personalised information such as name or reference number, you must provide their values in a dictionary with key value pairs. For example:

"personalisation": {
  "first_name": "Amala",
  "application_date": "2018-01-01",
}

You can leave out this argument if a template does not have any placeholder fields for personalised information.

reference (optional)

An identifier you can create if necessary. This reference identifies a single notification or a batch of notifications. It must not contain any personal information such as name or postal address. For example:

"reference": "STRING"

You can leave out this argument if you do not have a reference.

sms_sender_id (optional)

A unique identifier of the sender of the text message notification.

To find the text message sender:

  1. Sign in to GOV.UK Notify.
  2. Go to the Settings page.
  3. In the Text Messages section, select Manage on the Text Message sender row.

You can then either:

  • copy the sender ID that you want to use and paste it into the method
  • select Change to change the default sender that the service will use, and select Save
"sms_sender_id": "8e222534-7f05-4972-86e3-17c5d9f894e2"

You can leave out this argument if your service only has one text message sender, or if you want to use the default sender.

Response

If the request is successful, the response body is json with a status code of 201:

{
  "id": "740e5834-3a29-46b4-9a6f-16142fde533a",
  "reference": "STRING",
  "content": {
    "body": "MESSAGE TEXT",
    "from_number": "SENDER"
  },
  "uri": "https://api.notifications.service.gov.uk/v2/notifications/740e5834-3a29-46b4-9a6f-16142fde533a",
  "template": {
    "id": "f33517ff-2a88-4f6e-b855-c550268ce08a",
    "version": 1,
    "uri": "https://api.notifications.service.gov.uk/v2/template/ceb50d92-100d-4b8b-b559-14fa3b091cd"
  }
}

If you are using the test API key, all your messages will come back with a delivered status.

All messages sent using the team and whitelist or live keys will appear on your dashboard.

Error codes

If the request is not successful, the response body is json, refer to the table below for details.

status_code message How to fix
400 [{
"error": "BadRequestError",
"message": "Can't send to this recipient using a team-only API key"
]}
Use the correct type of API key
400 [{
"error": "BadRequestError",
"message": "Can't send to this recipient when service is in trial mode - see https://www.notifications.service.gov.uk/trial-mode"
}]
Your service cannot send this notification in trial mode
403 [{
"error": "AuthError",
"message": "Error: Your system clock must be accurate to within 30 seconds"
}]
Check your system clock
403 [{
"error": "AuthError",
"message": "Invalid token: API key not found"
}]
Use the correct API key. Refer to API keys for more information
429 [{
"error": "RateLimitError",
"message": "Exceeded rate limit for key type TEAM/TEST/LIVE of 3000 requests per 60 seconds"
}]
Refer to API rate limits for more information
429 [{
"error": "TooManyRequestsError",
"message": "Exceeded send limits (LIMIT NUMBER) for today"
}]
Refer to service limits for the limit number
500 [{
"error": "Exception",
"message": "Internal server error"
}]
Notify was unable to process the request, resend your notification.

Send an email

POST /v2/notifications/email

Request body

{
  "email_address": "sender@something.com",
  "template_id": "f33517ff-2a88-4f6e-b855-c550268ce08a"
}

Arguments

email_address (required)

The email address of the recipient.

template_id (required)

To find the template ID:

  1. Sign in to GOV.UK Notify.
  2. Go to the Templates page and select the relevant template.
  3. Select Copy template ID to clipboard.

personalisation (optional)

If a template has placeholder fields for personalised information such as name or reference number, you need to provide their values in a dictionary with key value pairs. For example:

"personalisation": {
  "first_name": "Amala",
  "application_date": "2018-01-01",
}

You can leave out this argument if a template does not have any placeholder fields for personalised information.

reference (optional)

An identifier you can create if necessary. This reference identifies a single notification or a batch of notifications. It must not contain any personal information such as name or postal address. For example:

"reference": "STRING"

You can leave out this argument if you do not have a reference.

email_reply_to_id (optional)

This is an email address specified by you to receive replies from your users. You must add at least one reply-to email address before your service can go live.

To add a reply-to email address:

  1. Sign in to GOV.UK Notify.
  2. Go to the Settings page.
  3. In the Email section, select Manage on the Reply-to email addresses row.
  4. Select Add reply-to address.
  5. Enter the email address you want to use, and select Add.

For example:

"email_reply_to_id": "8e222534-7f05-4972-86e3-17c5d9f894e2"

You can leave out this argument if your service only has one reply-to email address, or you want to use the default email address.

Send a file by email

To send a file by email, add a placeholder to the template then upload a file. The placeholder will contain a secure link to download the file.

The links are unique and unguessable. GOV.UK Notify cannot access or decrypt your file.

Add contact details to the file download page

  1. Sign in to GOV.UK Notify.
  2. Go to the Settings page.
  3. In the Email section, select Manage on the Send files by email row.
  4. Enter the contact details you want to use, and select Save.

Add a placeholder to the template

  1. Sign in to GOV.UK Notify.
  2. Go to the Templates page and select the relevant email template.
  3. Select Edit.
  4. Add a placeholder to the email template using double brackets. For example:

“Download your file at: ((link_to_file))”

Upload your file

You can upload PDF, CSV, .odt, .txt and MS Word Document files. Your file must be smaller than 2MB. Contact the GOV.UK Notify team if you need to send other file types. You’ll need to convert the file into a string that is base64 encoded.

Pass the encoded string into an object with a file key, and put that in the personalisation argument. For example:

"personalisation":{
  "first_name": "Amala",
  "application_date": "2018-01-01",
  "link_to_file": {"file": "file as base64 encoded string"},
}

Response

If the request to the client is successful, the client returns a dict:

{
  "id": "740e5834-3a29-46b4-9a6f-16142fde533a",
  "reference": "STRING",
  "content": {
    "subject": "SUBJECT TEXT",
    "body": "MESSAGE TEXT",
    "from_email": "SENDER EMAIL"
  },
  "uri": "https://api.notifications.service.gov.uk/v2/notifications/740e5834-3a29-46b4-9a6f-16142fde533a",
  "template": {
    "id": "f33517ff-2a88-4f6e-b855-c550268ce08a",
    "version": 1,
    "uri": "https://api.notifications.service.gov.uk/v2/template/f33517ff-2a88-4f6e-b855-c550268ce08a"
  }
}

Error codes

If the request is not successful, the response body is json, refer to the table below for details.

status_code message How to fix
400 [{
"error": "BadRequestError",
"message": "Can't send to this recipient using a team-only API key"
]}
Use the correct type of API key
400 [{
"error": "BadRequestError",
"message": "Can't send to this recipient when service is in trial mode - see https://www.notifications.service.gov.uk/trial-mode"
}]
Your service cannot send this notification in trial mode
400 [{
"error": "BadRequestError",
"message": "Unsupported file type '(FILE TYPE)'. Supported types are: '(ALLOWED TYPES)"
}]
Wrong file type. You can only upload .pdf, .csv, .txt, .doc, .docx or .odt files
400 [{
"error": "BadRequestError",
"message": "File did not pass the virus scan"
}]
The file contains a virus
400 [{
"error": "BadRequestError",
"message": "Send files by email has not been set up - add contact details for your service at https://www.notifications.service.gov.uk/services/(SERVICE ID)/service-settings/send-files-by-email"
}]
See how to add contact details to the file download page
403 [{
"error": "AuthError",
"message": "Error: Your system clock must be accurate to within 30 seconds"
}]
Check your system clock
403 [{
"error": "AuthError",
"message": "Invalid token: API key not found"
}]
Use the correct API key. Refer to API keys for more information
429 [{
"error": "RateLimitError",
"message": "Exceeded rate limit for key type TEAM/TEST/LIVE of 3000 requests per 60 seconds"
}]
Refer to API rate limits for more information
429 [{
"error": "TooManyRequestsError",
"message": "Exceeded send limits (LIMIT NUMBER) for today"
}]
Refer to service limits for the limit number
500 [{
"error": "Exception",
"message": "Internal server error"
}]
Notify was unable to process the request, resend your notification.

Send a letter

When you add a new service it will start in trial mode. You can only send letters when your service is live.

To send Notify a request to go live:

  1. Sign in to GOV.UK Notify.
  2. Go to the Settings page.
  3. In the Your service is in trial mode section, select request to go live.
POST /v2/notifications/letter

Request body

{
  "template_id": "f33517ff-2a88-4f6e-b855-c550268ce08a",
  "personalisation": {
    "address_line_1": "The Occupier",
    "address_line_2": "123 High Street",
    "postcode": "SW14 6BH"
  }
}

Arguments

template_id (required)

To find the template ID:

  1. Sign in to GOV.UK Notify.
  2. Go to the Templates page and select the relevant template.
  3. Select Copy template ID to clipboard.

personalisation (required)

The personalisation argument always contains the following required parameters for the letter recipient’s address:

  • address_line_1
  • address_line_2
  • postcode (this needs to be a real UK postcode)

Any other placeholder fields included in the letter template also count as required parameters. You need to provide their values in a dictionary with key value pairs. For example:

"personalisation":{
  "address_line_1": "The Occupier",
  "address_line_2": "123 High Street",
  "postcode": "SW14 6BF",
  "name": "John Smith",
  "application_id": "4134325"
}

reference (optional)

An identifier you can create if necessary. This reference identifies a single notification or a batch of notifications. It must not contain any personal information such as name or postal address. For example:

"reference":"STRING"

personalisation (optional)

The following parameters in the letter recipient’s address are optional:

"personalisation": {
  "address_line_3": "123 High Street",
  "address_line_4": "Richmond upon Thames",
  "address_line_5": "London",
  "address_line_6": "Middlesex",
}

Response

If the request is successful, the response body is json and the status code is 201:

{
  "id": "740e5834-3a29-46b4-9a6f-16142fde533a",
  "reference": "STRING",
  "content": {
    "subject": "SUBJECT TEXT",
    "body": "LETTER TEXT"
  },
  "uri": "https://api.notifications.service.gov.uk/v2/notifications/740e5834-3a29-46b4-9a6f-16142fde533a",
  "template": {
    "id": "f33517ff-2a88-4f6e-b855-c550268ce08a",
    "version": 1,
    "uri": "https://api.notifications.service.gov.uk/v2/template/f33517ff-2a88-4f6e-b855-c550268ce08a"
  },
  "scheduled_for": ""
}

Error codes

If the request is not successful, the response body is json, refer to the table below for details.

status_code message How to fix
400 [{
"error": "BadRequestError",
"message": "Can't send letters with a team API key"
]}
Use the correct type of API key
400 [{
"error": "BadRequestError",
"message": "Can't send letters when service is in trial mode - see https://www.notifications.service.gov.uk/trial-mode"
}]
Your service cannot send this notification in trial mode
400 [{
"error": "ValidationError",
"message": "personalisation address_line_1 is a required property"
}]
Ensure that your template has a field for the first line of the address, check personalisation for more information.
400 [{
"error": "ValidationError",
"message": "Must be a real UK postcode"
}]
Ensure that the value for the postcode field in your letter is a real UK postcode
403 [{
"error": "AuthError",
"message": "Error: Your system clock must be accurate to within 30 seconds"
}]
Check your system clock
403 [{
"error": "AuthError",
"message": "Invalid token: API key not found"
}]
Use the correct API key. Refer to API keys for more information
429 [{
"error": "RateLimitError",
"message": "Exceeded rate limit for key type TEAM/TEST/LIVE of 3000 requests per 60 seconds"
}]
Refer to API rate limits for more information
429 [{
"error": "TooManyRequestsError",
"message": "Exceeded send limits (LIMIT NUMBER) for today"
}]
Refer to service limits for the limit number
500 [{
"error": "Exception",
"message": "Internal server error"
}]
Notify was unable to process the request, resend your notification.

Send a precompiled letter

POST /v2/notifications/letter

Request body

{
  "reference": "STRING",
  "content": "STRING"
}

Arguments

reference (required)

An identifier you can create if necessary. This reference identifies a single notification or a batch of notifications. It must not contain any personal information such as name or postal address.

pdf_file (required)

The precompiled letter must be a PDF file which meets the GOV.UK Notify PDF letter specification. You’ll need to convert the file into a string that is base64 encoded.

"content": "base64EncodedPDFFile"

postage (optional)

You can choose first or second class postage for your precompiled letter. Set the value to first for first class, or second for second class. If you do not pass in this argument, the postage will default to second class.

"postage": "second"

Response

If the request is successful, the response body is json and the status code is 201:

{
  "id": "740e5834-3a29-46b4-9a6f-16142fde533a",
  "reference": "your-letter-reference",
  "postage": "postage-you-have-set-or-None"
}

Error codes

If the request is not successful, the response body is json, refer to the table below for details.

status_code message How to fix
400 [{
"error": "BadRequestError",
"message": "Can't send letters with a team API key"
]}
Use the correct type of API key
400 [{
"error": "BadRequestError",
"message": "Letter content is not a valid PDF"
]}
PDF file format is required
400 [{
"error": "BadRequestError",
"message": "Can't send letters when service is in trial mode - see https://www.notifications.service.gov.uk/trial-mode"
}]
Your service cannot send this notification in trial mode
400 [{
"error": "ValidationError",
"message": "reference is a required property"
}]
Add a reference argument to the method call
400 [{
"error": "ValidationError",
"message": "postage invalid. It must be either first or second."
}]
Change the value of postage argument in the method call to either ‘first’ or ‘second’
429 [{
"error": "RateLimitError",
"message": "Exceeded rate limit for key type live of 10 requests per 20 seconds"
}]
Use the correct API key. Refer to API keys for more information
429 [{
"error": "TooManyRequestsError",
"message": "Exceeded send limits (50) for today"
}]
Refer to service limits for the limit number

Get message status

Message status depends on the type of message you have sent.

You can only get the status of messages that are 7 days old or newer.

Status - email

Status Information
Created GOV.UK Notify has placed the message in a queue, ready to be sent to the provider. It should only remain in this state for a few seconds.
Sending GOV.UK Notify has sent the message to the provider. The provider will try to deliver the message to the recipient for up to 72 hours. GOV.UK Notify is waiting for delivery information.
Delivered The message was successfully delivered.
Failed This covers all failure statuses:
- permanent-failure - “The provider could not deliver the message because the email address was wrong. You should remove these email addresses from your database.”
- temporary-failure - “The provider could not deliver the message. This can happen when the recipient’s inbox is full. You can try to send the message again.”
- technical-failure - “Your message was not sent because there was a problem between Notify and the provider.
You’ll have to try sending your messages again.”

Status - text message

Status Information
Created GOV.UK Notify has placed the message in a queue, ready to be sent to the provider. It should only remain in this state for a few seconds.
Sending GOV.UK Notify has sent the message to the provider. The provider will try to deliver the message to the recipient for up to 72 hours. GOV.UK Notify is waiting for delivery information.
Pending GOV.UK Notify is waiting for more delivery information.
GOV.UK Notify received a callback from the provider but the recipient’s device has not yet responded. Another callback from the provider determines the final status of the notification.
Sent / Sent internationally The message was sent to an international number. The mobile networks in some countries do not provide any more delivery information. The GOV.UK Notify client API returns this status as sent. The GOV.UK Notify client app returns this status as Sent internationally.
Delivered The message was successfully delivered.
Failed This covers all failure statuses:
- permanent-failure - “The provider could not deliver the message. This can happen if the phone number was wrong or if the network operator rejects the message. If you’re sure that these phone numbers are correct, you should contact GOV.UK Notify support. If not, you should remove them from your database. You’ll still be charged for text messages that cannot be delivered.”
- temporary-failure - “The provider could not deliver the message. This can happen when the recipient’s phone is off, has no signal, or their text message inbox is full. You can try to send the message again. You’ll still be charged for text messages to phones that are not accepting messages.”
- technical-failure - “Your message was not sent because there was a problem between Notify and the provider.
You’ll have to try sending your messages again. You will not be charged for text messages that are affected by a technical failure.”

Status - letter

Status information
Failed The only failure status that applies to letters is technical-failure. GOV.UK Notify had an unexpected error while sending to our printing provider.
Accepted GOV.UK Notify has sent the letter to the provider to be printed.
Received The provider has printed and dispatched the letter.

Status - precompiled letter

Status information
Pending virus check GOV.UK Notify has not completed a virus scan of the precompiled letter file.
Virus scan failed GOV.UK Notify found a potential virus in the precompiled letter file.
Validation failed Content in the precompiled letter file is outside the printable area. See the GOV.UK Notify PDF letter specification for more information.

Get the status of one message

GET /v2/notifications/{notification_id}

Query parameters

notification_id (required)

The ID of the notification. You can find the notification ID in the response to the original notification method call.

You can also find it by signing in to GOV.UK Notify and going to the API integration page.

You can filter the returned messages by including the following optional parameters in the URL:

Response

If the request is successful, the response body is json and the status code is 200:

{
  "id": "740e5834-3a29-46b4-9a6f-16142fde533a", # required string - notification ID
  "reference": "STRING", # optional string
  "email_address": "sender@something.com",  # required string for emails
  "phone_number": "+447900900123",  # required string for text messages
  "line_1": "ADDRESS LINE 1", # required string for letter
  "line_2": "ADDRESS LINE 2", # required string for letter
  "line_3": "ADDRESS LINE 3", # optional string for letter
  "line_4": "ADDRESS LINE 4", # optional string for letter
  "line_5": "ADDRESS LINE 5", # optional string for letter
  "line_6": "ADDRESS LINE 6", # optional string for letter
  "postcode": "STRING", # required string for letter, must be a real UK postcode
  "type": "sms / letter / email", # required string
  "status": "sending / delivered / permanent-failure / temporary-failure / technical-failure", # required string
  "template": {
    "Version": 1
    "id": "f33517ff-2a88-4f6e-b855-c550268ce08a" # required string - template ID
    "uri": "/v2/template/{id}/{version}", # required
  },
  "body": "STRING", # required string - body of notification
  "subject": "STRING" # required string for email - subject of email
  "created_at": "STRING", # required string - date and time notification created
  "created_by_name": "STRING", # optional string - name of the person who sent the notification if sent manually
  "sent_at": "STRING", # optional string - date and time notification sent to provider
  "completed_at:" "STRING" # optional string - date and time notification delivered or failed
}

Error codes

If the request is not successful, the response body is json, refer to the table below for details.

status_code message How to fix
400 [{
"error": "ValidationError",
"message": "id is not a valid UUID"
}]
Check the notification ID
403 [{
"error": "AuthError",
"message": "Error: Your system clock must be accurate to within 30 seconds"
}]
Check your system clock
403 [{
"error": "AuthError",
"message": "Invalid token: API key not found"
}]
Use the correct API key. Refer to API keys for more information
404 [{
"error": "NoResultFound",
"message": "No result found"
}]
Check the notification ID

Get the status of multiple messages

This API call returns one page of up to 250 messages and statuses. You can get either the most recent messages, or get older messages by specifying a particular notification ID in the older_than argument.

You can only get the status of messages that are 7 days old or newer.

GET /v2/notifications

All messages

This will return all your messages with statuses. They will display in pages of up to 250 messages each.

You can filter the returned messages by including the following optional arguments in the URL:

Arguments

You can omit any of these arguments to ignore these filters.

template_type (optional)

You can filter by:

  • email
  • sms
  • letter

status (optional)

You can filter by each:

You can leave out this argument to ignore this filter.

reference (optional)

An identifier you can create if necessary. This reference identifies a single notification or a batch of notifications. It must not contain any personal information such as name or postal address. For example:

"reference": "STRING"

older_than (optional)

Input the ID of a notification into this argument. If you use this argument, the method returns the next 250 received notifications older than the given ID.

"older_than":"740e5834-3a29-46b4-9a6f-16142fde533a"

If you leave out this argument, the method returns the most recent 250 notifications.

The client only returns notifications that are 7 days old or newer. If the notification specified in this argument is older than 7 days, the client returns an empty response.

Response

If the request is successful, the response body is json and the status code is 200.

All messages

{
  "notifications": [
    {
      "id": "740e5834-3a29-46b4-9a6f-16142fde533a", # required string - notification ID
      "reference": "STRING", # optional string - client reference
      "email_address": "sender@something.com",  # required string for emails
      "phone_number": "+447900900123",  # required string for text messages
      "line_1": "ADDRESS LINE 1", # required string for letter
      "line_2": "ADDRESS LINE 2", # required string for letter
      "line_3": "ADDRESS LINE 3", # optional string for letter
      "line_4": "ADDRESS LINE 4", # optional string for letter
      "line_5": "ADDRESS LINE 5", # optional string for letter
      "line_6": "ADDRESS LINE 6", # optional string for letter
      "postcode": "STRING", # required for string letter, must be a real UK postcode
      "type": "sms / letter / email", # required string
      "status": "sending / delivered / permanent-failure / temporary-failure / technical-failure", # required string
      "template": {
        "version": 1
        "id": 'f33517ff-2a88-4f6e-b855-c550268ce08a' # required string - template ID
        "uri": "/v2/template/{id}/{version}", # required
      },
      "body": "STRING", # required string - body of notification
      "subject": "STRING" # required string for email - subject of email
      "created_at": "STRING", # required string - date and time notification created
      "created_by_name": "STRING", # optional string - name of the person who sent the notification if sent manually
      "sent_at": " STRING", # optional string - date and time notification sent to provider
      "completed_at": "STRING" # optional string - date and time notification delivered or failed
    },
    
  ],
  "links": {
    "current": "/notifications?template_type=sms&status=delivered",
    "next": "/notifications?other_than=last_id_in_list&template_type=sms&status=delivered"
  }
}

Error codes

If the request is not successful, the response body is json, refer to the table below for details.

status_code message How to fix
400 [{
"error": "ValidationError",
"message": "id is not a valid UUID"
}]
Check the notification ID
403 [{
"error": "AuthError",
"message": "Error: Your system clock must be accurate to within 30 seconds"
}]
Check your system clock
403 [{
"error": "AuthError",
"message": "Invalid token: API key not found"
}]
Use the correct API key. Refer to API keys for more information
404 [{
"error": "NoResultFound",
"message": "No result found"
}]
Check the notification ID

Testing

All testing takes place in the production environment. There is no test environment for GOV.UK Notify.

Smoke testing

If you need to smoke test your integration with Notify on a regular basis, you must use the following smoke test phone numbers and email addresses.

 
Phone number
07700900000
07700900111
07700900222
Email address
simulate-delivered@notifications.service.gov.uk
simulate-delivered-2@notifications.service.gov.uk
simulate-delivered-3@notifications.service.gov.uk

The smoke test phone numbers and email addresses will validate the request and simulate a successful response, but will not send a real message, produce a delivery receipt or persist the notification to the database.

You can use these smoke test numbers and addresses with any type of API key.

You can smoke test all Notify API client functions except:

  • Get the status of one message
  • Get the status of all messages

You cannot use the smoke test phone numbers or email address with these functions because they return a fake notification_ID. If you need to test these functions, use a test API key and any other phone number or email.

Other testing

You must use a test API key to do non-smoke testing such as performance or integration testing. You can use any non-smoke testing phone numbers or email addresses. You do not need a specific Notify testing account.

API keys

There are three different types of API keys:

  • test
  • team and whitelist
  • live

When you set up a new service it will start in trial mode. A service in trial mode can create test and team and whitelist keys. You must have a live service to create a live key.

To create an API key:

  1. Sign in to GOV.UK Notify.
  2. Go to the API integration page.
  3. Select API keys.
  4. Select Create an API key.

Test

Use a test key to test the performance of your service and its integration with GOV.UK Notify.

Messages sent using a test key:

  • generate realistic responses
  • result in a delivered status
  • are not actually delivered to a recipient
  • do not appear on your dashboard
  • do not count against your text message and email allowances

To test failure responses with a test key, use the following numbers and addresses:

Phone number/Email address Response
07700900003 temporary-failure
07700900002 permanent-failure
temp-fail@simulator.notify temporary-failure
perm-fail@simulator.notify permanent-failure
any other valid number or address delivered

You do not have to revoke test keys.

Team and guest list

A team and guest list key lets you send real messages to your team members and addresses/numbers on your guest list while your service is still in trial mode.

You will get an error if you use these keys to send messages to anyone who is not on your team or your guest list.

Messages sent with a team and guest list key appear on your dashboard and count against your text message and email allowances.

You do not have to revoke team and guest list keys.

Live

You can only create live keys once your service is live. You can use live keys to send messages to anyone.

Messages sent with a live key appear on your dashboard and count against your text message and email allowances.

You should revoke and re-create these keys on a regular basis. To revoke a key:

  1. Sign in to GOV.UK Notify.
  2. Go to the API integration page.
  3. Select API keys.
  4. Select Revoke for the API key you want to revoke.

You can have more than one active key at a time.

You should never send test messages to invalid numbers or addresses using a live key.

Limits

Rate limits

You’re limited to sending 3,000 messages per minute.

This limit is calculated on a rolling basis, per API key type. If you exceed the limit, you will get a 429 error RateLimitError.

Daily limits

There’s a limit to the number of messages you can send each day:

Service status Type of API key Daily limit
Live Team or live 250,000
Trial Team 50
Live or trial Test Unlimited

These limits reset at midnight.

Phone network limits

If you repeatedly send text messages to the same number the phone networks will block them.

There’s an hourly limit of:

  • 20 messages with the same content
  • 100 messages with any content

Your messages may not be delivered if you exceed these limits.

Callbacks

Callbacks are when GOV.UK Notify sends POST requests to your service. You can get callbacks when:

  • a text message or email you’ve sent is delivered or fails
  • your service receives a text message

Set up callbacks

You must provide:

  • a URL where Notify will post the callback to
  • a bearer token which Notify will put in the authorisation header of the requests

To do this:

  1. Sign in to GOV.UK Notify.
  2. Go to the API integration page.
  3. Select Callbacks.

Delivery receipts

When you send an email or text message, Notify will send a receipt to your callback URL with the status of the message. This is an automated method to get the status of messages.

This functionality works with test API keys, but does not work with smoke testing phone numbers or email addresses.

The callback message is formatted in JSON. The key, description and format of the callback message arguments will be:

Key Description Format
id Notify’s id for the status receipts UUID
reference The reference sent by the service 12345678
to The email address or phone number of the recipient hello@gov.uk or 07700912345
status The status of the notification delivered, permanent-failure, temporary-failure or technical-failure
created_at The time the service sent the request 2017-05-14T12:15:30.000000Z
completed_at The last time the status was updated 2017-05-14T12:15:30.000000Z or nil
sent_at The time the notification was sent 2017-05-14T12:15:30.000000Z or nil
notification_type The notification type email or sms

Received text messages

If your service receives text messages in Notify, Notify can forward them to your callback URL as soon as they arrive.

Contact the Notify team using the support page or chat to us on Slack to request a unique number for text message replies.

The callback message is formatted in JSON. The key, description and format of the callback message arguments will be:

Key Description Format
id Notify’s id for the received message UUID
source_number The phone number the message was sent from 447700912345
destination_number The number the message was sent to (your number) 07700987654
message The received message Hello Notify!
date_received The UTC datetime that the message was received by Notify 2017-05-14T12:15:30.000000Z

API architecture

Send a message

Get message status

Get inbound messages

Support

Report any problems via the GOV.UK Notify support page.

You can also: