SMTP relay integration | Brevo API Documentation

Use the SMTP relay to send transactional emails from your email client or application. Send order confirmations, password resets, account creation notifications, and other automated messages.

SMTP credentials

Retrieve your SMTP username and password from SMTP and API settings. Under the “SMTP” tab, copy existing credentials or generate new ones.

Use an SMTP key, not an API key, for SMTP relay connections.

Connection settings

Ports:

Non-encrypted: Use ports 587 or 2525
Encrypted: Use port 465 with SSL or TLS encryption

Encryption:

Leave empty unless using port 465, which requires SSL or TLS encryption

SMTP parameters

The following parameters are available for SMTP relay messages:

Parameter	Type	Description	Example
`sender`	Object	Sender information. Required if `templateId` is not provided. Pass `name` (optional) and `email`, or `id`. If `id` is provided, `name` is ignored.	`{"name":"Support", "email":"no-reply@brevo.com"}` or `{"id":2}`
`to`	Array of objects	Recipient email addresses and names (optional). Required if `messageVersions` is not provided. Ignored if `messageVersions` is provided.	`[{"name":"John", "email":"john@example.com"}]`
`bcc`	Array of objects	BCC recipient email addresses and names (optional).	`[{"name":"Admin", "email":"admin@example.com"}]`
`cc`	Array of objects	CC recipient email addresses and names (optional).	`[{"name":"Manager", "email":"manager@example.com"}]`
`htmlContent`	String	HTML body of the message. Required if `templateId` is not provided. Ignored if `templateId` is provided.	`<!DOCTYPE html><html><body><p>Content</p></body></html>`
`textContent`	String	Plain text body of the message. Ignored if `templateId` is provided.	`"Plain text content"`
`subject`	String	Email subject line. Required if `templateId` is not provided.	`"Your order confirmation"`
`replyTo`	Object	Reply-to email address (required) and name (optional).	`{"email":"support@brevo.com", "name":"Support Team"}`
`attachment`	Array of objects	Attachments. Provide absolute URL (no local files) or base64-encoded content with attachment name. Name is required if content is provided.	See attachment object attributes below
`headers`	Object	Custom headers (non-standard) to include in the email.	`{"X-Custom-Header":"value"}`
`templateId`	Int64	Template ID to use for the email.	`2`
`params`	Object	Template variables for customization. Only applies to templates using New Template Language format.	`{"FNAME":"John", "LNAME":"Doe"}`
`messageVersions`	Array of objects	Multiple message versions with personalized content. See API reference for details.	Contains multiple versions with same sender and recipient parameters
`tags`	Array of strings	Tags to categorize and filter emails.	`["order", "confirmation"]`
`scheduledAt`	date-time	UTC date-time for scheduled delivery (YYYY-MM-DDTHH:mm:ss.SSSZ). Include timezone. Expected delay of up to 5 minutes. Currently in public beta.	`2022-04-05T12:30:00+02:00`
`batchId`	String	UUIDv4 batch identifier for scheduled batch transactional emails. Auto-generated if not provided.	`5c6cfa04-eed9-42c2-8b5c-6d470d978e9d`

Sender object

Attribute	Type	Description	Example
`name`	String	Sender display name. Maximum 70 characters. Only applicable when `email` is provided.	`"Support Team"`
`email`	String	Sender email address. Required if `id` is not provided.	`"no-reply@brevo.com"`
`id`	Int64	Sender ID. Use to select a sender with a specific IP pool. Required if `email` is not provided.	`2`

Recipient objects (to, bcc, cc)

Attribute	Type	Description	Example
`email`	String	Recipient email address.	`"user@example.com"`
`name`	String	Recipient display name. Maximum 70 characters.	`"John Doe"`

Reply-to object

Attribute	Type	Description	Example
`email`	String	Reply-to email address.	`"support@brevo.com"`
`name`	String	Reply-to display name. Maximum 70 characters.	`"Support Team"`

Attachment object

Attribute	Type	Description	Example
`url`	URL	Absolute URL of the attachment. Local files are not supported.	`"https://example.com/attachment.pdf"`
`content`	String	Base64-encoded attachment content.	`"b3JkZXIucGRm"`
`name`	String	Attachment filename. Required if `content` is provided.	`"invoice.pdf"`

Headers object

Custom headers are key-value pairs. The key is the header name, and the value is the header value. Only non-standard headers are supported.

The SMTP relay does not support batch sending. Use the batch sending API endpoints for batch operations. The SMTP relay is designed for transactional emails.

To improve deliverability for B2B emails, consult Brevo IP ranges from the help center.