Email Deliverability

Deliverability vs Delivered: Why Your 98% ‘Success Rate’ Might Be Lying

May 8, 2025

If your email tool is bragging about a 98% delivery rate, hold the celebration — because that number doesn’t mean what you think it does.

Most email platforms are only measuring delivery, not deliverability. And there's a big difference.

Delivered ≠ Inboxed

Let’s define it clearly:

A message can be delivered but never seen. Because being delivered to the Spam folder, the Promotions tab, or corporate quarantine isn’t the goal.

Your goal is simple: visibility.

Why That “98% Delivered” Metric Is Misleading

Here’s why it doesn’t tell the whole story:

Spam and Promotions still count as 'delivered'
Silent drops (emails discarded by filters) are marked as delivered
False positives from bots loading images can inflate open rates

So if your outreach isn’t getting replies, your deliverability might be broken — even with a 98% delivery rate.

Mailbox providers care about trust. If you’re not authenticating properly, building your reputation gradually, or engaging your audience — you’ll end up flagged, filtered, or ignored.

What Actually Impacts Inbox Placement

There are multiple technical and behavioral signals that email providers look at when deciding where your email goes:

These are all evaluated before your copy is even read. The decision to inbox or spam you is made in milliseconds — and it’s not based on your “open rate.”

What You Should Be Tracking Instead

Let’s fix the metrics mindset. Here are the KPIs that actually matter:

1. Inbox Placement Rate (IPR)

What it is: % of emails that land in the Primary Inbox (not Promotions/Spam)
How to test it:

2. Reply Rate

Real human replies = you landed in a real inbox
Use this as your gold standard KPI for deliverability

3. Positive Reply Rate

Are people responding with interest, questions, or meetings?
Even "Not now" is better than silence — it means they saw you

4. Lead-to-Meeting Rate

Ultimate goal: Did your cold email create pipeline?

5. Domain & IP Reputation Monitoring

Use Google Postmaster Tools for domain health
Use Microsoft SNDS for Outlook sender rep (if you own the IPs or are using dedicated IPs)
Run blacklist checks on Talos Intelligence or MXToolbox
Use Mission Inbox’s rep dashboard to track trust signals daily

How to Fix Poor Deliverability

Step 1: Fix Your Infrastructure

Set up and align SPF, DKIM, and DMARC (use strict alignment settings)
Avoid using links entirely.

Step 2: Build Reputation the Right Way

Warm up new domains slowly
Send from aged domains if possible
Keep bounce rates below 2% and spam complaints near 0%
Avoid sudden sending volume spikes

Step 3: Send Better Emails

Ditch the templates — write like a human
Personalize beyond {FirstName}
Keep HTML minimal or send in plain text
Avoid phrases like “Act Now,” “FREE,” “Only 2 Left!”
Use Mission Inbox’s spam check engine to flag risky language, broken headers, or domain mismatches before you hit send