Scheduling email campaigns becomes more complex when you need to send email to millions of recipients at the unique time best suited for each customer. Consider these examples: The scheduling requirements involve multiple considerations. You’re sending hundreds of millions of messages, each at its own optimal moment personalized to the recipient’s time zone and behavior. In this post, we walk through how to use Amazon EventBridge Scheduler to personalize email notifications to each recipient.
We create one schedule per recipient to deliver each email at its individually optimal moment, with zero idle compute cost. We also show how Amazon EventBridge Scheduler handles higher volumes. Amazon EventBridge Scheduler supports billions of schedules. By default, you have a quota of 10 million schedules . When every recipient has their own ideal delivery time, you need a scheduling layer that can hold billions of individual send intents and fire each one at the right moment. Most teams reach for one of three familiar patterns, each with tradeoffs that become painful at scale.
All three approaches either sacrifice precision (batching), hit architectural limits (delay queues), or surrender control (third-party tools). Amazon EventBridge Scheduler treats each email send as a discrete scheduled action. Instead of “process all messages due this hour,” you express the intent directly: “send this email to this person at this time. ” Amazon EventBridge Scheduler holds that intent with zero compute cost until the moment arrives, then triggers the scheduled action. See the Amazon EventBridge Scheduler User Guide for the full API reference and current service quotas.
For email campaigns, Amazon EventBridge Scheduler becomes the send-time dispatcher , the component that schedules every email in a campaign for its individually optimal moment, whether that’s timezone-adjusted, behavior-triggered, or sequence-driven. The architecture follows an event-driven, per-recipient scheduling pattern for an email campaign. To start the campaign, you first define the target audience and the content they receive. Next, you need a way to create the per-recipient schedule. To do that for a campaign that can contain millions of recipients, you need a scalable mechanism to create the schedules.