Send-time optimization
Send-time optimization (STO) delivers each message at the time each individual contact is most likely to engage — turning scheduled campaigns into per-person precision.
How it works
When you enable STO on a campaign, Active Reach doesn’t send everything at once. Instead, it:
- Analyzes each contact’s engagement history — when they’ve opened, clicked, and responded in the past
- Identifies their optimal engagement window — the time of day and day of week they’re most active
- Distributes delivery across the campaign’s send window, delivering to each contact at their personal best time
If a contact is new (no engagement history yet), the platform falls back to the best time for similar contacts in the same segment and region.
How to enable it
In the campaign builder (Advanced mode):
- Go to Scheduling
- Instead of “Send now” or “Schedule”, select Send-time optimization
- Set a delivery window — the date range within which the platform can send (e.g., “over the next 24 hours” or “this week”)
- Launch the campaign
The platform handles the rest. Delivery spreads across the window, peaking at each contact’s optimal time.
When to use it
| Scenario | Use STO? |
|---|---|
| Marketing newsletter | Yes — engagement varies by person |
| Promotional offer (time-sensitive, 2-hour flash sale) | No — urgency matters more than personalization |
| Onboarding sequence (triggered immediately after signup) | No — timeliness matters more |
| Weekly product recommendations | Yes — ideal for per-person timing |
| Cart abandonment (within 1 hour) | No — fast delivery is critical |
What it optimizes for
The optimization target is engagement — opens, clicks, and replies. The platform continuously learns from each new interaction. The model improves over time as more contact-level data accumulates.
STO works best when you have at least 2 weeks of engagement data for a contact. New workspaces see full benefit after the first month of regular sending.
Analytics
STO campaigns show an additional “Delivery distribution” chart in their analytics — a heatmap of when messages were actually delivered, overlaid with engagement rates per hour. This helps you understand your audience’s behavior patterns.