Add sender account

curl --request POST \
  --url https://api.coldsend.io/api/public/v1/sender-accounts \
  --header 'Content-Type: application/json' \
  --header 'X-API-Key: <api-key>' \
  --data '
{
  "email_address": "<string>",
  "display_name": "<string>",
  "inbox_type": "<string>",
  "smtp_host": "<string>",
  "smtp_port": 32768,
  "smtp_username": "<string>",
  "smtp_password": "<string>",
  "imap_host": "<string>",
  "imap_port": 32768,
  "imap_username": "<string>",
  "imap_password": "<string>",
  "daily_limit": 100,
  "smtp_use_tls": true,
  "imap_use_ssl": true
}
'

{
  "success": true,
  "message": "<string>",
  "inbox_id": "3c90c3cc-0d44-4b50-8888-8dd25736052a",
  "email_address": "<string>",
  "display_name": "<string>",
  "inbox_type": "<string>",
  "daily_limit": 123,
  "overall_status": "<string>",
  "created_at": "2023-11-07T05:31:56Z"
}

Sender Accounts

Add sender account

Add your own email account for sending campaigns (BYOC)

Connect your existing email accounts to ColdSend for sending cold emails.

Supported Email Providers

GOOGLE_WORKSPACE: Gmail/Google Workspace (smtp.gmail.com:587)
OUTLOOK_365: Microsoft Outlook (smtp.office365.com:587)
CUSTOM_SMTP: Any custom SMTP provider

Security Notes

Always use App Passwords, never your main email password.

Example Usage

import requests

response = requests.post(
    "https://api.coldsend.io/api/public/v1/sender-accounts",
    headers={"X-API-Key": "your-api-key"},
    json={
        "email_address": "[email protected]",
        "display_name": "John Smith",
        "inbox_type": "GOOGLE_WORKSPACE",
        "daily_limit": 50,
        "smtp_host": "smtp.gmail.com",
        "smtp_port": 587,
        "smtp_username": "[email protected]",
        "smtp_password": "your-app-password",
        "smtp_use_tls": True,
        "imap_host": "imap.gmail.com",
        "imap_port": 993,
        "imap_username": "[email protected]",
        "imap_password": "your-app-password",
        "imap_use_ssl": True
    }
)

POST

api

public

sender-accounts

Add sender account

curl --request POST \
  --url https://api.coldsend.io/api/public/v1/sender-accounts \
  --header 'Content-Type: application/json' \
  --header 'X-API-Key: <api-key>' \
  --data '
{
  "email_address": "<string>",
  "display_name": "<string>",
  "inbox_type": "<string>",
  "smtp_host": "<string>",
  "smtp_port": 32768,
  "smtp_username": "<string>",
  "smtp_password": "<string>",
  "imap_host": "<string>",
  "imap_port": 32768,
  "imap_username": "<string>",
  "imap_password": "<string>",
  "daily_limit": 100,
  "smtp_use_tls": true,
  "imap_use_ssl": true
}
'

{
  "success": true,
  "message": "<string>",
  "inbox_id": "3c90c3cc-0d44-4b50-8888-8dd25736052a",
  "email_address": "<string>",
  "display_name": "<string>",
  "inbox_type": "<string>",
  "daily_limit": 123,
  "overall_status": "<string>",
  "created_at": "2023-11-07T05:31:56Z"
}

Authorizations

X-API-Key

string

header

required

API key with format cs_live_xxx

Query Parameters

Body

application/json

Request to add a workspace email inbox (BYOC: Bring Your Own Credentials).

Connect your existing email account to ColdSend for sending campaigns. You maintain full control over your email infrastructure while leveraging ColdSend's automation. Workspace inboxes are unlimited for paid plans.

email_address

string

required

Full email address to connect (e.g., [email protected]). Should be a real, working email account. Best practice: Use dedicated accounts for cold email separate from personal/operational email.

Required string length: 5 - 255

display_name

string

required

Display name shown in recipient's inbox (e.g., 'John Smith from Company'). Best practice: Include your real name and company for authenticity. Avoid ALL CAPS or excessive punctuation.

Required string length: 1 - 255

inbox_type

string

required

Email provider type: GOOGLE_WORKSPACE (Google Workspace/G Suite), OUTLOOK_365 (Microsoft 365/Outlook.com), or CUSTOM_SMTP (any other provider with SMTP/IMAP access). Each has different daily limits.

smtp_host

string

required

SMTP server hostname for sending emails. Common: smtp.gmail.com (Gmail), smtp.office365.com (Outlook), or your provider's SMTP server. Always use encrypted connections (TLS/SSL).

Required string length: 1 - 255

smtp_port

integer

required

SMTP server port number. Standard ports: 587 (STARTTLS, recommended), 465 (SSL/TLS, legacy). Most providers use port 587 with TLS encryption.

Required range: 1 <= x <= 65535

smtp_username

string

required

SMTP authentication username. Usually your full email address (e.g., [email protected]). Some providers may use a different format. This credential is encrypted at rest using AES-256.

Required string length: 1 - 255

smtp_password

string

required

SMTP authentication password or app-specific password. CRITICAL: Use an app-specific password, NOT your main account password. App passwords are more secure and required when 2FA is enabled. This password is encrypted at rest.

Required string length: 1 - 500

imap_host

string

required

IMAP server hostname for monitoring replies. Common: imap.gmail.com (Gmail), outlook.office365.com (Outlook). ColdSend uses IMAP to monitor inbox for replies, stop sequences when prospects respond, and track engagement.

Required string length: 1 - 255

imap_port

integer

required

IMAP server port number. Standard ports: 993 (SSL/TLS, recommended), 143 (STARTTLS, less common). Almost all providers use port 993 with SSL encryption.

Required range: 1 <= x <= 65535

imap_username

string

required

IMAP authentication username. Usually your full email address, same as SMTP username. Must be the same account as SMTP to ensure reply tracking works correctly. This credential is encrypted at rest.

Required string length: 1 - 255

imap_password

string

required

IMAP authentication password or app-specific password. Use the SAME app-specific password as SMTP (in most cases). Both SMTP and IMAP typically use the same authentication credentials. This password is encrypted at rest.

Required string length: 1 - 500

daily_limit

integer

default:100

Daily sending limit for this inbox. Controls how many emails can be sent per day across all campaigns. Recommended: 20-30 for new accounts, 50-80 for warming accounts, 80-100 for established accounts. Start low and increase gradually.

Required range: x >= 1

smtp_use_tls

boolean

default:true

Enable TLS encryption for SMTP connection. Strongly recommended to keep enabled. TLS encrypts the connection protecting your credentials and email content. Disable only if provider explicitly requires unencrypted connection.

imap_use_ssl

boolean

default:true

Enable SSL/TLS encryption for IMAP connection. Strongly recommended to keep enabled. SSL/TLS encrypts the connection for secure inbox monitoring. Port 993 requires SSL. Disable only if provider explicitly requires unencrypted connection.

Response

Sender account added successfully

Response for workspace inbox creation.

success

boolean

required

message

string

required

inbox_id

string<uuid>

required

Created inbox ID

email_address

string

required

Email address

display_name

string

required

Display name

inbox_type

string

required

Inbox provider type

daily_limit

integer

required

Daily send limit

overall_status

string

required

Inbox status

created_at

string<date-time>

required

Creation timestamp

List sender accounts Get sender account

⌘I

Campaigns

Sender Accounts

Domains

Leads

Scopes

Add sender account

Supported Email Providers

Security Notes

Example Usage

Authorizations

Query Parameters

Body

Response