A warmup schedule is your roadmap for building sender reputation. The right schedule balances growth speed with reputation safety. Here is a proven approach.
Standard 8-Week Warmup Schedule
| Week | Daily Volume | Weekly Total | Subscriber Segment |
|---|---|---|---|
| 1 | 200 | 1,400 | Most engaged (opened in last 30 days) |
| 2 | 500 | 3,500 | Recent engagers (60 days) |
| 3 | 1,000 | 7,000 | Engaged subscribers (90 days) |
| 4 | 2,500 | 17,500 | Active subscribers (6 months) |
| 5 | 5,000 | 35,000 | Expand if metrics healthy |
| 6 | 10,000 | 70,000 | Most of active list |
| 7 | 20,000 | 140,000 | Full active list |
| 8 | Target volume | Target | Normal sending |
Schedule Principles
Start Small
Begin with 200-500 daily emails, even if your target is millions. This establishes a baseline of good behavior before providers see significant volume.
Increase Gradually
Increase volume by 25-50% per step (daily or weekly, depending on your pace). Sudden jumps trigger spam detection.
Best Subscribers First
During warmup, send only to subscribers most likely to engage:
- Recent purchasers or active users
- Opened email in last 30 days
- Clicked email in last 60 days
- Subscribed recently (last 90 days)
Engaged recipients generate positive signals that accelerate warmup.
Consistent Daily Sending
Send every day during warmup. Consistent patterns build trust faster than sporadic bursts.
Adapt to Your Situation
This schedule is a starting point. If you have excellent engagement rates, you may increase faster. If you see any problems, slow down. Metrics determine the pace, not the calendar.
Metrics to Monitor
At Each Stage, Check:
- Bounce rate: Should stay under 2%
- Complaint rate: Should stay under 0.1%
- Inbox placement: Test with seed lists
- Deferrals: Watch for "try again later" responses
- Open/click rates: Should match historical benchmarks
Green Light to Increase
- Bounces under 1%
- Complaints under 0.05%
- Good inbox placement
- No throttling messages
Yellow Light: Proceed Cautiously
- Bounces 1-2%
- Complaints 0.05-0.1%
- Some throttling
Maintain current volume for another period before increasing.
Red Light: Stop and Diagnose
- Bounces above 2%
- Complaints above 0.1%
- Significant blocking or filtering
- Blocklist entries
Reduce volume, identify the problem, fix it, then resume carefully.
Provider-Specific Considerations
Gmail
Gmail is typically the most sensitive to new senders. Consider warming up Gmail recipients separately and more slowly if they represent a large portion of your list.
Microsoft (Outlook, Hotmail)
Microsoft may defer messages during warmup. This is normal throttling. Do not retry aggressively; let their suggested retry intervals guide you.
Yahoo
Yahoo generally warms up similarly to Gmail. Monitor their specific feedback via their postmaster tools.
Do Not Skip Steps
It is tempting to accelerate when things go well, but reputation systems need time. A week at each volume level is not just about sending mail; it is about giving providers time to evaluate your behavior.
After Warmup Completes
- Maintain consistent sending patterns
- Avoid sudden volume spikes (keep increases under 30%)
- Continue monitoring metrics
- Warm up again if you stop sending for extended periods