warmup-playbook.md

Warmup & Reputation Recovery Playbook

The step-by-step process for warming up new senders or recovering damaged sender reputation, built from managing IP pools that process 10-18 million messages a day. Follow it exactly — the order matters.

When to Use This Playbook

New domain or IP needs warming before production sending
Sender has been blocklisted and needs reputation recovery
Open rates have cratered (below 10%) and domain reputation is damaged
Migrating from another ESP and need to establish reputation on new infrastructure

Phase 1: The Pause (Week 1)

Do NOT send bulk email. Do NOT do nothing.

This week is for data analysis and preparation. The rule is emphatic: "Don't do nothing during that week. During that week, it's generally spent on data analysis."

Step 1: Assess Current State

Pull current open rates by mailbox provider (Gmail, Microsoft, Yahoo, iCloud, ProofPoint)
Check domain reputation in Google Postmaster Tools
Run SpamHaus check on all sending domains and IPs
Check all authentication records (SPF, DKIM, DMARC) are present and valid
Verify HELO/reverse DNS match on every IP

Step 2: Analyze Historical Performance

For promotional senders: Identify the best-performing offers. "What are the best offers that you've sent?"
For newsletter senders: Identify the most engaging topics. "What are the most salient topics that your audience likes?"
Goal: Have a strong piece of content ready to launch when sending resumes.

Step 3: Segment the Audience

Build these segments from most to least engaged:

Recently signed up — Opted in within the last 30 days. Highest natural engagement.
Super fans — Your most email-engaged subscribers. "Every brand has their super fans. They love the interaction. They love it when you send them email."
Regular engaged — Opened or clicked within the last 90 days.
Lightly engaged — Opened within the last 180 days.
Inactive — No engagement in 180+ days. These come last, if at all.

Step 4: Segment by Mailbox Provider

Within each engagement tier, create sub-segments by mailbox provider:

Gmail
Microsoft (Outlook/Hotmail)
Yahoo
iCloud/Apple
ProofPoint-filtered domains
Other

Start your warmup with Gmail contacts who have engaged with an email in the last 90 days. Gmail is the largest provider and provides the clearest reputation signals via Google Postmaster Tools. Starting with recently engaged Gmail contacts gives you the highest chance of strong initial engagement, which builds positive domain reputation that carries over when you expand to other providers.

Real-world example: "I did a warmup on Klaviyo a while back. I ended up having to manage eight segments because they had a substantial consumer and B2B audience... seven material buckets of mailbox provider and spam filter plus the other category."

Step 5: Validate the Data

Run list hygiene on the entire list
Remove hard bounces, soft bounces from previous ESP
Sample and evaluate data risk with validation tools
Check for spam trap indicators (custom-hosted domains on their own nameservers with 5-letter names)

"When you move onto a new ESP, I want to validate your data just because mistakes happen. Data sets — bounces sometimes will remain in the list."

Phase 2: The Ramp (Weeks 2-6+)

Starting Volumes by Provider (Reputation Recovery)

When restarting from severely damaged reputation:

Provider	Day 1 Volume	Ramp Rule
Microsoft	25 emails	Never send more than 4x previous day's opens
Yahoo	50 emails	Never send more than 4x previous day's opens
Gmail	200 emails	Never send more than 4x previous day's opens
iCloud	50 emails	Fixed schedule, not the 4x rule — MPP inflates opens here. Under 10% open rate at iCloud = severe issue

Starting Volumes (New Domain/IP Warmup)

When warming from scratch (not damaged, just new):

Days 1-7: Send only automated/transactional volume (a few hundred per day)
Week 2: Begin blending in engaged audience segments
Week 3+: Gradually introduce less engaged segments
Target timeline: 1-2 months to reach 100K/day (depends on audience engagement quality)

New Domain Requirements

New domains need a 90-day aging period before heavy sending use
Consider aftermarket domains that already have age — they cost $1-200 depending on keywords
Look for domains with keywords relevant to the brand (e.g., "blitz" and "games" for a gaming company)
Even aged domains need sending warmup — domain age helps but isn't sufficient alone

Daily Management During Ramp

Each day during the warmup:

Check yesterday's metrics by provider segment
Identify who opened/clicked (these people are "done" for this campaign cycle)
Update segments: remove already-mailed contacts, add next batch
Send to the next day's segment — only people who haven't received this campaign yet
Monitor bounce rates, complaint rates, and inbox placement
If any provider shows warning signs, reduce volume or pause for that provider

The manual process: "Literally update those every day and say okay, well today I sent to the last one to three days of engaged people at ProofPoint, Microsoft, Gmail, Hotmail, whatever."

Automated Warmup (When Available)

With proper tooling, you can load the full weekly segment and let the system manage distribution: "Load up a whole 10,000 segment and just let our warmup schedule run it all out of that one campaign without you having to really do a lot about it. Other than watch it and check the metrics."

Phase 3: Steady State

When to Declare Victory

Open rates consistently above 20% across providers
Domain reputation "High" in Google Postmaster Tools
No active blocklist entries
Soft bounce rate under 0.5%
Complaint rate under 0.1%

Ongoing Monitoring

Check domain/IP reputation weekly
Monitor open rate trends (direction matters more than absolute number)
Watch for provider-specific drops (one provider declining while others hold = provider-specific issue)
Validate new list imports before sending
Maintain engagement-based suppression (sunset inactive contacts)

For Casino/iGaming Clients

More aggressive sunsetting required:

Suppress users after 3-5 unopened emails (not the standard 90-180 day window)
Monthly newsletter sends should be spread across the month, not spiked on one day
Large campaigns can be spread across 3-4 days rather than a single send

Content Strategy During Warmup

Best Practice: Identical Content Approach

Send the same newsletter content to both engaged AND disengaged audiences:

Engaged audience sends first → builds positive content reputation
Same content then reaches disengaged users → benefits from the positive reputation already established
This is more effective than sending different content to different segments

Launch Content

Use your strongest-performing content type for the first send
Ensure perfect branding, clean HTML, proper images
Include plain text version
Keep links minimal
Avoid trigger words (URGENT, ACTION REQUIRED, etc.)

Transactional Email First

If warming a completely new domain:

Start with automated/transactional emails (OTP codes, order confirmations)
These have fewer links and higher natural engagement
Build initial reputation before adding marketing volume

Setting Client Expectations

How to set expectations honestly:

On the pause: "Not going to be a lot of volume going out. It's really going to be curated sends to small segments."

On timeline: Reputation recovery takes weeks to months, not days. "You just got to let that kind of rest for a little bit."

On the upside: "If you're fully inboxing, you're going to be getting 10X that kind of engagement." Frame the pause as an investment, not a loss.

On list cuts: "It's truly not the size. It's how it performs and how much money it makes you." Be prepared to cut 10-20% of a list for quality.

On the long game: "For me, email is about the long game, not the short game. Yes, there are short-term things you need to do in the interim to keep everything afloat, but really keeping your email reputation high is part of building a sustainable business."

Warmup playbook