Sending Mail

Mail can be sent via the following methods:

Sending mail, both replies and new messages, is available only from private addresses and private domains. Sending or replying requires mail credits.

Sent messages are not save using any method, with the exception of the Unified Inbox.

Sending from the Web Form

The Web Form is the easiest way to get started sending mail through mailsac.

  1. Use the Web Form or select Compose New Email from the Dashboard
  2. Fill in the From, To, Subject, and Text fields
  3. Click Send

Sending from the Unified Inbox

The Unified Inbox allows you to send and receive like you would with gmail or yahoo mail.

  1. Go to the Unified Inbox or select Unified Inbox from the Dashboard

  2. Select compose from the Unified Inbox

  3. Select the from address in the from dropdown, fill out the to address, subject, and text.

  4. Click Send to send the message.

Sending from the REST API

The REST API is the preferred method for sending messages programmattically. The /api-outgoing-messages endpoint is documented in the API documentation.

  1. Generate an API by selecting API Keys from the Dashboard.

  2. Send email using curl or your favorite HTTP library.

    curl -H "Mailsac-Key: w9Hc8j8dhh2jeE1VS9VEKt4nxE0JsHLM" -X POST
    -H "Content-Type: application/json" --data '{ "to":"", "from": "",
    "subject": "Hello Myfriend", "text": "test message from mailsac" }'
    import requests
    url = ''
    headers = {'Mailsac-Key': 'w9Hc8j8dhh2jeE1VS9VEKt4nxE0JsHLM'}
    mail = { 'to':'', 'from':'', 'subject':'Hello Myfriend', 'text': 'mailsac allows for sending of email'}
    x =, data=mail, headers=headers)

Sending with SMTP

Sending via SMTP allows email clients to send email using mailsac.


SMTP uses a username and passowrd for authentication. The API key for your account can be used to send from any of your private addresses or domains. Alternatively, you can use a per private address SMTP password. The per private address SMTP password can be set through using the Dashboard -> Manage Email Addresses -> Select the POP/SMTP button next to the email address -> Select Set New Password


Email Client Configuration

Configure your email client (Gmail, Apple mail, Thunberbird, Outlook, iPhone, etc) using these SMTP settings:

Hostname / Server
Email Address Private email address
Username Private email address
Password API Key or SMTP Key
Port 587
Auth Settings Password / allow plain / insecure
Encryption TLS

Sent Messages Are Not Saved

Outgoing messages are not saved. They may be visible or cached temporarily by our outgoing mail services, and logged in debugging messages on Mailsac servers, but not explicitly archived by Mailsac at this time.