Set up a Customer Reactivation or Order Follow-up workflow and don't want to wait for new orders to send it? Retrospective triggering lets you include contacts who already took the trigger action before you enabled the automation – as long as they fall within your first delay timeframe.
Key point: Contacts follow the same delay as if the event just happened. They don't receive messages immediately.
Before You Begin
Retrospective triggering only works with event-based triggers (Order Placed, Subscribed to Marketing, Product Viewed) – not time-based or segment-based triggers.
Your automation must start with a Delay block. The delay determines how far back Omnisend looks (e.g., 30-day delay = includes events from the past 30 days).
Retrospective triggering is enabled by default in Customer Reactivation and Order Follow-up presets for Shopify, BigCommerce, and API integrations. For other platforms or custom workflows, you'll enable it manually.
Contacts receive messages based on when they triggered the event, not immediately. See timing example below.
Which Method Should I Use?
Your Goal | Use This Method |
Send to contacts who triggered events in the past (Order Placed, Subscribed) – with delay timing | Retrospective triggering (this article) |
Send immediately to all existing contacts in a segment | |
Send one-time email to past buyers |
Not sure? If your automation is event-based (Order Placed, Abandoned Cart, Subscribed) and you want to respect delay timing, use retrospective triggering.
Retrospective Automations
Where to Find the Setting
For presets (Customer Reactivation, Order Follow-up):
The "Trigger retrospectively" toggle is enabled by default. You can turn it off if you only want the automation to apply to future events.
For custom workflows:
Go to Automations → Create Workflow → Create from Scratch.
Select an event-based trigger (Order Placed, Subscribed to Marketing, etc.).
Click the Trigger block.
Scroll down → Toggle "Trigger retrospectively" on.
Add a Delay block as the first step in your workflow.
Enable the automation.
Platform Notes
Shopify, BigCommerce, API integrations: Retrospective triggering is enabled by default in Customer Reactivation and Order Follow-up presets.
WooCommerce, other platforms: Presets trigger retrospectively automatically. If you don't want retrospective triggering, create a custom workflow with the same trigger instead.
💡 Tip: If you want to trigger a different workflow retrospectively (e.g., Order Feedback, Cross-Sell), use the Order Follow-up preset, then save your email design as a template and swap the content.
How Does It Work?
When you enable an automation with retrospective triggering, Omnisend looks back at contacts who took the trigger action before the workflow was enabled – but only within the timeframe of your first delay.
Example: Customer Reactivation
Today: You enable Customer Reactivation with a 30-day delay.
20 days ago: A customer placed an order.
What happens: That customer will receive the first email 10 days from today (30-day delay – 20 days already passed = 10 days remaining).
Contacts added from the past do not receive messages immediately. They enter the workflow as if the event just happened and follow the delay timing.
⚠️ Important Limitations
Delay block required: Retrospective triggering only works if your automation starts with a Delay block. No delay = no retrospective triggering.
First delay determines lookback window: If your first delay is 30 days, Omnisend includes contacts whose event happened in the past 30 days. Contacts outside this window (e.g., 35 days ago) will not enter the workflow.
Order status check: For order-based automations, retrospective triggering checks the last order status at the time of enabling. Only orders with "Placed" status trigger the workflow.
Send Welcome Automations to Existing Subscribers
Welcome automation does not support retrospective triggering because it's designed for new subscribers only. If you need to send a welcome message to existing contacts, use one of these methods:
Option 1: Send a Campaign
Save your Welcome email design as a template, then send a one-time Email Campaign to a segment of existing subscribers.
Option 2: Segment-Based Automation
Create a segment of existing subscribers (e.g., "Subscribed to Email is true").
Go to Automations → Create Workflow → Create from Scratch.
Select "Contact enters a segment" as the trigger.
Choose your segment.
Check "Trigger workflow for contacts in the segment" (includes all current segment members immediately).
Enable the workflow.
Troubleshooting
Editing Enabled Automations
If you edit an automation that's already enabled (e.g., change delay timing or trigger filters), retrospective triggering may not apply correctly to past contacts. For best results:
Duplicate the workflow.
Configure retrospective triggering in the new draft.
Enable the new workflow and disable the old one.
FAQ
Can I manually trigger an automation for specific contacts?
You can't add contacts to an automation manually, but you can use a workaround:
Create a segment with only the contacts you want (e.g., using "Email address is" filters or "Placed order" + "Product title is X"). Learn how to create segments.
Create a segment-based automation with "Contact enters a segment" as the trigger.
Check "Trigger workflow for contacts in the segment" before enabling.
Enable the workflow – all current segment members receive the automation immediately.
Why can't I check "Trigger retrospectively"?
The "Trigger retrospectively" toggle is only available for event-based triggers (Order Placed, Subscribed, etc.). It won't appear for:
Segment-based triggers ("Contact enters a segment") – use the "Trigger workflow for contacts in segment" checkbox instead.
Time-based triggers (e.g., Anniversary, Recurring).
Automations without a Delay block.
If you're using an event-based trigger and still don't see it:
Ensure you've selected an event (not a segment) as the trigger.
Add a Delay block as the first step in your workflow.
Save the workflow and check the Trigger block settings again.
I set up an automation after contacts had already subscribed/placed orders. How do I include them?
If your automation is event-based (Order Placed, Subscribed):
Enable "Trigger retrospectively" in the Trigger block settings. Contacts whose event happened within your first delay timeframe will enter the workflow.If you need immediate sends or the automation doesn't support retrospective triggering:
Use a segment-based automation with "Trigger workflow for contacts in the segment" checked.
Does retrospective triggering send messages immediately?
No. Contacts follow the same delay timing as if they triggered the event when you enabled the workflow.
Example:
Today: Enable automation with 30-day delay.
Customer ordered 20 days ago.
Email sends: 10 days from today (30 – 20 = 10).
If you need immediate sends, use segment-based triggering or send a Campaign instead.
Can I use both retrospective triggering and segment-based triggering together?
No. These are two separate methods:
Retrospective triggering: For event-based automations. Includes past events within delay timeframe.
Segment-based triggering: For immediate sends to all current segment members.
Choose the method that fits your use case. For most "include existing contacts" scenarios, segment-based triggering is simpler.
What's the easiest way to send an automation to a list of specific contacts right now?
For one-time sends: Create a segment with the contacts you want (e.g., "Placed order" + "Product title is X"), then send an Email Campaign to that segment.
For ongoing sends: Use a segment-based automation with "Trigger workflow for contacts in the segment" checked. This includes all current segment members immediately and continues for future contacts who enter the segment.
Why can't I check "Trigger workflow for contacts in the segment"?
This checkbox is only available for new workflows that have never been enabled. Once a workflow has been started (even if later disabled), the option is permanently locked. To use it: Duplicate your workflow and enable the checkbox in the new draft version before activating.
Why didn't my Customer Reactivation workflow add past customers?
Retrospective triggering only looks back as far as your first delay. If your workflow has a 30-day delay, only customers who placed an order within the last 30 days will be added – orders from 35+ days ago are excluded.
Also ensure:
You're using the preset workflow (not a custom workflow).
The first block after the trigger is a Delay (no Splits or other blocks before it).
Which automations can be triggered retrospectively?
Retrospective triggering is available for event-based workflows that use presets:
Customer Reactivation
Order Follow-up
Product Reviews (Order Fulfilled trigger)
Replenishment Reminder (Order Fulfilled trigger)
It does not work for transaction-only workflows like Shipping Confirmation or Order Refund. For non-event workflows (e.g., Welcome), use the segment-based "Trigger workflow for contacts in the segment" method instead.
Will past contacts receive my emails immediately when I enable a retrospective workflow?
No. Contacts added from the past move through the workflow based on when they originally took the action, not when you enabled the workflow.
Example: If your workflow has a 30-day delay and a customer placed an order 20 days ago, they'll receive the first email 10 days from today.
If you still have any questions or need any assistance, do not hesitate to contact our support team via in-app chat or at [email protected].