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ArticleDeliverability & Infrastructure

Microsoft Deliverability Blueprint

I'm sharing our secret sauce our clients get 5-15% reply rates on Microsoft contacts.

IlyaIlya AzovtsevCo-founder1 min read
Ilya Azovtsev amazed, hands framing his face, under the words 90% lost, beside a clay trash can full of emails and an inbox badge.
On this pageHow we’ve cracked Microsoft’s Algo
  1. How we’ve cracked Microsoft’s Algo
  2. Quick reminder:

90% of your emails to Microsoft recipients never land.

Even if your copy is perfect. Even if your offer is great.

They just don't see it.

We cracked it 🧙

Microsoft Deliverability Blueprint

→ Watch the full Microsoft Deliverability Blueprint

Here's why this matters:

The bigger the company you're targeting, the more likely they use Microsoft.

  • SMBs: 90% Google, 10% Microsoft
  • Mid-market: 70/30
  • Enterprise: Often 50/50 or Microsoft-heavy

If you're selling upmarket, you're losing half your pipeline due to the deliverability.

How we’ve cracked Microsoft’s Algo

15,000+ mailboxes managed. 300+ B2B teams.

Our clients get 5-12% reply rates on Microsoft-only audiences.

Campaign stats for a Microsoft-only audience: 12K sent, 6.71% reply rate, 99.13% delivery rate and 26 interested leads

Here's the blueprint:

1. Analyze your ESP mix Use MX Toolbox (free) to see what % of your audience is on Microsoft.

2. Build separate infrastructure Microsoft needs its own setup. Don't mix it with Google.

3. Azure SMTP + Enterprise IP Not Google mailboxes. Not Outlook. Azure SMTP with enterprise-level IP.

4. The ratios

  • 1 domain = 10 mailboxes
  • 5 emails/day per mailbox
  • That's 50 emails/day per domain

5. Premium warm-up Outlook-specific pools. 3 weeks minimum. Cheap warm-up = ruined deliverability.

6. Rotation buffer Keep 10-30% extra domains warming. When one burns, swap immediately.

7. Clean copy No links. No HTML. No tracking pixels. Plain text only.

8. Monitor the 96% threshold Inbox placement drops below 96%? Rotate that domain.

❌ Who this is NOT for:

If you're only targeting startups and SMBs, Google optimization is usually enough. Skip this.

✅ Who this IS for:

Anyone selling to mid-market or enterprise where Microsoft usage is 30%+. This is the difference between replies and radio silence.

Quick reminder:

We build and operate this infrastructure for B2B teams.

You own the ICP and copy. We own deliverability.

If you want us to handle this for you → book a call

— Ilya

Get sending infrastructure that stays out of spam

We build and run your cold email infrastructure: domains, mailboxes, daily placement checks and a rotation pool.

Ilya

Ilya AzovtsevCo-founder

Co-founder of GrowthBand. Helped scale lemlist from $20k MRR to $10M ARR and built automation at Expandi; now runs the cold email infrastructure behind 32,000+ mailboxes.