Amazon SES Compatible API

If you’re currently using Amazon SES and want to migrate to SendPost, we offer Amazon SES Compatible APIs (v1 and v2) that minimize code changes. You only need to change the endpoint URL and replace AWS Signature authentication with a simple API key header.

Quick Migration Steps

Change the endpoint URL

SES v1
SES v2

From: https://email.{region}.amazonaws.com/
To: https://api.sendpost.io/api/v1/subaccount/email/ses/v1

From: https://email.{region}.amazonaws.com/v2/email/outbound-emails
To: https://api.sendpost.io/api/v1/subaccount/email/ses/v2

Update authentication

From: AWS Signature Version 4 (complex signing with access/secret keys)
To: X-SubAccount-ApiKey: YOUR_SENDPOST_API_KEY header

Keep your request body

Use the exact same SES v1 or v2 JSON request format - no changes needed!

Optional: Add SendPostOptions

Optionally add SendPostOptions to leverage SendPost-specific features like IP Pool routing

SES v1 Migration Example

Before (Amazon SES v1)
After (SendPost SES v1)

curl -X POST "https://email.us-east-1.amazonaws.com/" \
  -H "Authorization: AWS4-HMAC-SHA256 Credential=..." \
  -H "Content-Type: application/x-amz-json-1.0" \
  -d '{
    "Source": "sender@example.com",
    "Destination": {
      "ToAddresses": ["recipient@example.com"]
    },
    "Message": {
      "Subject": {
        "Data": "Hello World",
        "Charset": "UTF-8"
      },
      "Body": {
        "Text": {
          "Data": "Hello!",
          "Charset": "UTF-8"
        },
        "Html": {
          "Data": "<p>Hello!</p>",
          "Charset": "UTF-8"
        }
      }
    }
  }'

curl -X POST "https://api.sendpost.io/api/v1/subaccount/email/ses/v1" \
  -H "X-SubAccount-ApiKey: YOUR_SENDPOST_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{
    "Source": "sender@example.com",
    "Destination": {
      "ToAddresses": ["recipient@example.com"]
    },
    "Message": {
      "Subject": {
        "Data": "Hello World",
        "Charset": "UTF-8"
      },
      "Body": {
        "Text": {
          "Data": "Hello!",
          "Charset": "UTF-8"
        },
        "Html": {
          "Data": "<p>Hello!</p>",
          "Charset": "UTF-8"
        }
      }
    },
    "SendPostOptions": {
      "IPPool": "ses-pool"
    }
  }'

SES v2 Migration Example

Before (Amazon SES v2)
After (SendPost SES v2)

curl -X POST "https://email.us-east-1.amazonaws.com/v2/email/outbound-emails" \
  -H "Authorization: AWS4-HMAC-SHA256 Credential=..." \
  -H "Content-Type: application/x-amz-json-1.0" \
  -d '{
    "FromEmailAddress": "sender@example.com",
    "Destination": {
      "ToAddresses": ["recipient@example.com"]
    },
    "Content": {
      "Simple": {
        "Subject": {
          "Data": "Hello World",
          "Charset": "UTF-8"
        },
        "Body": {
          "Text": {
            "Data": "Hello!",
            "Charset": "UTF-8"
          },
          "Html": {
            "Data": "<p>Hello!</p>",
            "Charset": "UTF-8"
          }
        }
      }
    }
  }'

curl -X POST "https://api.sendpost.io/api/v1/subaccount/email/ses/v2" \
  -H "X-SubAccount-ApiKey: YOUR_SENDPOST_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{
    "FromEmailAddress": "sender@example.com",
    "Destination": {
      "ToAddresses": ["recipient@example.com"]
    },
    "Content": {
      "Simple": {
        "Subject": {
          "Data": "Hello World",
          "Charset": "UTF-8"
        },
        "Body": {
          "Text": {
            "Data": "Hello!",
            "Charset": "UTF-8"
          },
          "Html": {
            "Data": "<p>Hello!</p>",
            "Charset": "UTF-8"
          }
        }
      }
    },
    "SendPostOptions": {
      "IPPool": "ses-pool"
    }
  }'

Field Mappings

SES v1 → SendPost

SES v1 Field	SendPost Field	Notes
`Source`	`From.Email`, `From.Name`	Supports “Name <email>” format
`Destination.ToAddresses[]`	`To[].Email`	Direct mapping
`Destination.CcAddresses[]`	`To[].Cc[]`	Direct mapping
`Destination.BccAddresses[]`	`To[].Bcc[]`	Direct mapping
`Message.Subject.Data`	`Subject`	Direct mapping
`Message.Body.Text.Data`	`TextBody`	Direct mapping
`Message.Body.Html.Data`	`HtmlBody`	Direct mapping
`ReplyToAddresses[]`	`ReplyTo.Email`	First address only
`Tags[]`	`Groups[]`	Formatted as “Name:Value”
`SendPostOptions.IPPool`	`IPPool`	SendPost extension
`SendPostOptions.TrackOpens`	`TrackOpens`	SendPost extension
`SendPostOptions.TrackClicks`	`TrackClicks`	SendPost extension
`SendPostOptions.WebhookEndpoint`	`WebhookEndpoint`	SendPost extension

SES v2 → SendPost

SES v2 Field	SendPost Field	Notes
`FromEmailAddress`	`From.Email`, `From.Name`	Supports “Name <email>” format
`Destination.ToAddresses[]`	`To[].Email`	Direct mapping
`Destination.CcAddresses[]`	`To[].Cc[]`	Direct mapping
`Destination.BccAddresses[]`	`To[].Bcc[]`	Direct mapping
`Content.Simple.Subject.Data`	`Subject`	Only `Simple` content type supported
`Content.Simple.Body.Text.Data`	`TextBody`	Direct mapping
`Content.Simple.Body.Html.Data`	`HtmlBody`	Direct mapping
`ReplyToAddresses[]`	`ReplyTo.Email`	First address only
`EmailTags[]`	`Groups[]`	Formatted as “Name:Value”
`SendPostOptions.IPPool`	`IPPool`	SendPost extension
`SendPostOptions.TrackOpens`	`TrackOpens`	SendPost extension
`SendPostOptions.TrackClicks`	`TrackClicks`	SendPost extension
`SendPostOptions.WebhookEndpoint`	`WebhookEndpoint`	SendPost extension

SendPostOptions Extension

SendPost offers optional extensions through the SendPostOptions field that are not available in the standard SES API:

{
  "SendPostOptions": {
    "IPPool": "ses-pool",              // IP pool name for routing
    "TrackOpens": true,                 // Enable open tracking
    "TrackClicks": true,                // Enable click tracking
    "WebhookEndpoint": "https://..."    // Webhook URL for events
  }
}

Tracking Explained: Open and click events are tracked via Amazon SES’s configuration set (“sendpost-events”) and delivered to SendPost through SNS notifications. The TrackOpens and TrackClicks options in SendPostOptions control SendPost’s tracking pixels, which provide additional tracking when emails are processed by SendPost before being sent to SES. Both tracking methods work independently.

Supported SES Features

Feature	SES v1	SES v2	Notes
`Source` / `FromEmailAddress`	✅	✅	Supports “Name <email>” format
`Destination.ToAddresses`	✅	✅	Direct mapping
`Destination.CcAddresses`	✅	✅	Direct mapping
`Destination.BccAddresses`	✅	✅	Direct mapping
`Message.Subject` / `Content.Simple.Subject`	✅	✅	Direct mapping
`Message.Body.Text` / `Content.Simple.Body.Text`	✅	✅	Direct mapping
`Message.Body.Html` / `Content.Simple.Body.Html`	✅	✅	Direct mapping
`ReplyToAddresses`	✅	✅	First address only
`Tags` / `EmailTags`	✅	✅	Mapped to Groups as “Name:Value”
`SendPostOptions`	✅	✅	SendPost extension

Unsupported SES Features

The following SES features are not supported and will return a ValidationException error if present:

Feature	Alternative
`RawMessage` (v1)	Use `Message` with `Subject` and `Body` instead
`Content.Raw` (v2)	Use `Content.Simple` instead
`Template`, `TemplateData`, `TemplateArn` (v1)	Use SendPost’s native template API or include content directly
`Content.Template` (v2)	Use SendPost’s native template API or include content directly
`SourceArn`, `ReturnPath`, `ReturnPathArn` (v1)	Handled automatically by SendPost
`FromEmailAddressIdentityArn` (v2)	Not needed with SendPost
`FeedbackForwardingEmailAddress` (v2)	Handled automatically by SendPost
`ListManagementOptions` (v2)	Use SendPost’s `{{unsubscribe}}` template variable

Error Response for Unsupported Fields:

{
  "__type": "ValidationException",
  "message": "Field 'RawMessage' is not supported. Please use Message with Subject and Body instead."
}

Response Format

Success Response (HTTP 200)

{
  "MessageId": "550e8400-e29b-41d4-a716-446655440000"
}

Error Response (HTTP 400/403/413/429/500)

{
  "__type": "ValidationException",
  "message": "1 validation error detected: Value at 'Source' failed to satisfy constraint: Member must satisfy regular expression pattern: [\\u0020-\\u007E]+"
}

Error Types

Error Type	HTTP Status	Description
`ValidationException`	400	Invalid request format or missing required fields
`AccessDeniedException`	403	Invalid or missing API key
`MessageRejected`	400	Email rejected (e.g., domain not verified)
`MailFromDomainNotVerifiedException`	400	Domain not verified in SendPost
`MessageTooLarge`	413	Payload exceeds 10MB limit
`TooManyRequestsException`	429	Rate limit exceeded
`ServiceException`	500	Internal server error

Key Differences: SES v1 vs v2

Feature	SES v1	SES v2
Source field	`Source`	`FromEmailAddress`
Subject	`Message.Subject`	`Content.Simple.Subject`
Body	`Message.Body`	`Content.Simple.Body`
Tags	`Tags[]`	`EmailTags[]`
Content types	Simple only	Simple, Raw, Template (only Simple supported)

IP Pool Routing

When using the Amazon SES Compatible API, you can specify an IP Pool through SendPostOptions.IPPool. This IP Pool must be configured in SendPost to route traffic to your Amazon SES provider.

Important: The IP Pool specified in SendPostOptions.IPPool must exist in SendPost and be configured to route to your Amazon SES provider. If not specified, the default IP Pool will be used.

Next Steps

Understand event types for tracking email status
View analytics for your Amazon SES emails
Troubleshoot issues with the compatible API

Documentation

Guides

SDK Quickstarts

Common Use Cases

Amazon SES Compatible API

Quick Migration Steps

SES v1 Migration Example

SES v2 Migration Example

Field Mappings

SES v1 → SendPost

SES v2 → SendPost

SendPostOptions Extension

Supported SES Features

Unsupported SES Features

Response Format

Success Response (HTTP 200)

Error Response (HTTP 400/403/413/429/500)

Error Types

Key Differences: SES v1 vs v2

IP Pool Routing

Next Steps

Documentation

Guides

SDK Quickstarts

Common Use Cases

Documentation Index

​Quick Migration Steps

​SES v1 Migration Example

​SES v2 Migration Example

​Field Mappings

​SES v1 → SendPost

​SES v2 → SendPost

​SendPostOptions Extension

​Supported SES Features

​Unsupported SES Features

​Response Format

​Success Response (HTTP 200)

​Error Response (HTTP 400/403/413/429/500)

​Error Types

​Key Differences: SES v1 vs v2

​IP Pool Routing

​Next Steps

Quick Migration Steps

SES v1 Migration Example

SES v2 Migration Example

Field Mappings

SES v1 → SendPost

SES v2 → SendPost

SendPostOptions Extension

Supported SES Features

Unsupported SES Features

Response Format

Success Response (HTTP 200)

Error Response (HTTP 400/403/413/429/500)

Error Types

Key Differences: SES v1 vs v2

IP Pool Routing

Next Steps