We’ve made several new enhancements to our email API features, designed to give you more control, better performance and greater flexibility when sending emails at scale.
From scheduling emails in advance to dramatically improving throughput and sending large batches more efficiently, these updates make it easier than ever to integrate powerful email workflows into your applications.
Schedule Emails Up to 3 Days in Advance
We’ve added a new schedule property to our /email/send and /email/mime API endpoints, allowing you to schedule emails for delivery up to 3 days in advance.
This makes it easy to:
- Queue transactional emails ahead of peak periods
- Time-sensitive campaigns more precisely
- Spread out high-volume sends
- Improve operational workflows without external schedulers
New Schedule Tracking Support
When using the schedule property, the API will now return a schedule_id instead of an email_id.
This schedule_id can be used to:
- Track scheduled email delivery via webhooks
- Identify scheduled sends before delivery occurs
- Manage queued emails programmatically
In addition, scheduled emails will include a new email header:
None X-Smtp2go-Schedule-Id
This header can also be used alongside webhooks to monitor the lifecycle and delivery status of scheduled messages.
New Scheduled Email Management Endpoints
To support scheduled sending, we’ve introduced two new API endpoints for managing queued emails.
/email/scheduled/search
Retrieve a list of up to 1,000 scheduled emails matching the supplied search parameters.
This endpoint is ideal for:
- Auditing scheduled sends
- Monitoring pending delivery queues
- Building scheduling dashboards or admin tools
/email/scheduled/remove
Remove a scheduled email using its schedule_id.
This gives developers the flexibility to:
- Cancel pending emails
- Update workflows dynamically
- Prevent outdated or unnecessary messages from being sent
Boost Your API Sending Speed with fastaccept
We’ve also introduced a new optional parameter, fastaccept, to our email-sending API.
When enabled, fastaccept can significantly improve sending performance by allowing the API to acknowledge requests more quickly during high-throughput operations.
This is especially useful for:
- Large-scale transactional email systems
- Time-sensitive workloads
- Applications requiring lower API response latency
We plan to make fastaccept the default behavior in a future release, so now is a great time to begin testing and integrating it into your workflows.
For implementation details and examples, please refer to the API documentation.
Send Up to 1,000 Emails with the New Batch Endpoint
We’re also introducing a brand-new API endpoint:
None /email/batch
This endpoint allows you to send or schedule a batch of up to 1,000 emails in a single request.
Why Use Batch Sending?
Batch sending helps reduce:
- API request overhead
- Connection setup costs
- Processing latency
while simplifying large-scale email operations.
Use cases include:
- Bulk transactional notifications
- Multi-recipient workflows
- Scheduled bulk sends
- High-volume application messaging
The new endpoint supports both immediate sending and scheduled delivery, giving you maximum flexibility for managing large email workloads efficiently.
Designed for Scale and Flexibility
These updates are part of our ongoing effort to provide faster, more reliable and more scalable email infrastructure.
For full implementation details, examples and parameter documentation, check out the API documentation.
About the author
Charlotte James
Charlotte specialises in email deliverability and inbox placement. Writing for SMTP2GO since 2014, she has explored topics such as authentication protocols, bounce handling, deliverability strategies and real-world customer success stories. Her work focuses on helping senders navigate the technical and policy changes - from evolving ISP requirements to authentication standards - that influence email performance.
