Create blocked email sender

POST/accounts/{account_id}/email-security/settings/block_senders

Creates a new blocked sender pattern. Emails matching this pattern will be blocked from delivery. Patterns can be email addresses, domains, or IP addresses, and support regular expressions.

Security

API Token

The preferred authorization scheme for interacting with the Cloudflare API. Create a token.

Example:Authorization: Bearer Sn3lZJTBX6kkg7OdcBUAxOO963GEIyGQqnFTOFYY

API Email + API Key

The previous authorization scheme for interacting with the Cloudflare API, used in conjunction with a Global API key.

Example:X-Auth-Email: user@example.com

The previous authorization scheme for interacting with the Cloudflare API. When possible, use API tokens instead of Global API keys.

Example:X-Auth-Key: 144c9defac04969c7bfad8efaa8ea194

Accepted Permissions (at least one required)

Cloud Email Security: Write

Path ParametersExpand Collapse

account_id: string

Identifier.

maxLength32

Body ParametersJSONExpand Collapse

is_regex: boolean

pattern: string

maxLength1024

minLength1

pattern_type: "EMAIL" or "DOMAIN" or "IP" or "UNKNOWN"

Type of pattern matching. Note: UNKNOWN is deprecated and cannot be used when creating or updating policies, but may be returned for existing entries.

One of the following:

"EMAIL"

"DOMAIN"

"IP"

"UNKNOWN"

comments: optional string

maxLength1024

ReturnsExpand Collapse

errors: array of object { code, message, documentation_url, source }

code: number

minimum1000

message: string

documentation_url: optional string

source: optional object { pointer }

pointer: optional string

messages: array of object { code, message, documentation_url, source }

code: number

minimum1000

message: string

documentation_url: optional string

source: optional object { pointer }

pointer: optional string

success: true

Whether the API call was successful.

result: optional object { id, comments, created_at, 5 more }

A blocked sender pattern

id: optional string

Blocked sender pattern identifier

formatuuid

comments: optional string

maxLength1024

created_at: optional string

formatdate-time

is_regex: optional boolean

Deprecatedlast_modified: optional string

Deprecated, use modified_at instead. End of life: November 1, 2026.

formatdate-time

modified_at: optional string

formatdate-time

pattern: optional string

maxLength1024

minLength1

pattern_type: optional "EMAIL" or "DOMAIN" or "IP" or "UNKNOWN"

Type of pattern matching. Note: UNKNOWN is deprecated and cannot be used when creating or updating policies, but may be returned for existing entries.

One of the following:

"EMAIL"

"DOMAIN"

"IP"

"UNKNOWN"

Create blocked email sender

curl https://api.cloudflare.com/client/v4/accounts/$ACCOUNT_ID/email-security/settings/block_senders \
    -H 'Content-Type: application/json' \
    -H "Authorization: Bearer $CLOUDFLARE_API_TOKEN" \
    -d '{
          "is_regex": false,
          "pattern": "test@example.com",
          "pattern_type": "EMAIL",
          "comments": "Block sender with email test@example.com"
        }'

{
  "errors": [
    {
      "code": 1000,
      "message": "message",
      "documentation_url": "documentation_url",
      "source": {
        "pointer": "pointer"
      }
    }
  ],
  "messages": [
    {
      "code": 1000,
      "message": "message",
      "documentation_url": "documentation_url",
      "source": {
        "pointer": "pointer"
      }
    }
  ],
  "success": true,
  "result": {
    "id": "f174e90a-fafe-4643-bbbc-4a0ed4fc8415",
    "comments": "Block sender with email test@example.com",
    "created_at": "2014-01-01T05:20:00.12345Z",
    "is_regex": false,
    "last_modified": "2014-01-01T05:20:00.12345Z",
    "modified_at": "2014-01-01T05:20:00.12345Z",
    "pattern": "test@example.com",
    "pattern_type": "EMAIL"
  }
}

Returns Examples

{
  "errors": [
    {
      "code": 1000,
      "message": "message",
      "documentation_url": "documentation_url",
      "source": {
        "pointer": "pointer"
      }
    }
  ],
  "messages": [
    {
      "code": 1000,
      "message": "message",
      "documentation_url": "documentation_url",
      "source": {
        "pointer": "pointer"
      }
    }
  ],
  "success": true,
  "result": {
    "id": "f174e90a-fafe-4643-bbbc-4a0ed4fc8415",
    "comments": "Block sender with email test@example.com",
    "created_at": "2014-01-01T05:20:00.12345Z",
    "is_regex": false,
    "last_modified": "2014-01-01T05:20:00.12345Z",
    "modified_at": "2014-01-01T05:20:00.12345Z",
    "pattern": "test@example.com",
    "pattern_type": "EMAIL"
  }
}