A 99% delivery rate doesn’t guarantee your emails reached the inbox. It only means the receiving server accepted them. With DKIM2 expected to roll out across major mailbox providers, emails may be accepted initially and later rejected if spam filters determine they’re unwanted.
Brands relying on outdated deliverability metrics could see sudden increases in bounce rates and lower inbox placement.
Why you should read this article?
✅ Delivered doesn’t mean Inbox
✅ DKIM2 introduces delayed bounces
✅ Poor list hygiene will become much easier to detect
✅ Gmail may reject messages hours after accepting them
✅ Brands should audit authentication before 2027
Everyone celebrates a 99% delivery rate.
They probably shouldn’t.
Imagine this.
Your latest campaign finishes sending.
Your dashboard says:
Delivered: 99.2%
You celebrate it.
Everything looks healthy.
Then…
The next morning your ESP reports another 4% of your emails bounced.
Not because they were sent to invalid addresses.
Because Gmail decided (hours later) that they shouldn’t have stayed accepted.
Welcome to the future of email authentication.
“Delivered” Never meant “Inbox placed”
This surprises a lot of marketers and ecommerce managers.
Most ESPs define a delivered email as…
The receiving mail server accepted your message.
That’s it.
It doesn’t mean:
❌ someone received it
❌ it landed in Primary inbox
❌ it avoided Spam
❌ it was trusted
Think of it like shipping a package.
The courier accepted it.
That doesn’t mean it reached the customer’s front door.
For years… That distinction didn’t matter much.
DKIM2 changes that.
What Is DKIM2?
Imagine you’re trying to get into an exclusive nightclub.
The security guard checks your ID. Everything looks good.
“Come on in.”
Great.
You’re inside.
That’s how email deliverability works today.
Your email arrives at Gmail.
Gmail checks who sent it.
If everything looks okay, it accepts the message.
Most email platforms immediately count that as Delivered.
End of story.
Well…
Not anymore.
DKIM2 is like a second security check
Now imagine you’re already inside the club.
You’re dancing. Having a great time.
Then another security guard walks over.
He notices something suspicious.
Maybe your ID looks fake.
Maybe someone reported you.
Maybe something just doesn’t add up.
Instead of letting you stay…
He walks you back to the exit.
That’s essentially what DKIM2 is expected to do.
Instead of making one decision when your email arrives…
Mailbox providers may make another decision later.
If they decide your email looks suspicious… They can reject it—even after accepting it.
That’s called a delayed bounce.
And yes…
That changes everything.
Why DKIM2 matters for Email Deliverability
Here’s the part that catches people off guard.
Today your dashboard might say:
📨 100,000 emails sent
✅ 99,000 delivered
Looks amazing.
But under DKIM2, Gmail could come back hours later and say…
“Actually…4,000 of those shouldn’t have been accepted.”
Suddenly your numbers become:
📨 Sent: 100,000
✅ Delivered: 95,000
❌ Delayed Bounces: 4,000
Same campaign. Different reality.
Your email software didn’t lie.
It just didn’t know the final answer yet.
Why Google is doing this
Think about junk mail. Some letters are obviously spam.
Others look real.
At first. Maybe they have a real logo.
A professional design.
A familiar sender.
Only after looking more closely do you realize…
Something feels off.
That’s what Gmail wants to do. Instead of rushing the decision…
It wants more time to figure out whether your email deserves a place in the inbox.
That’s better for users.
But much tougher for brands with poor email practices.
Will DKIM2 hurt your brand / ecommerce?
Not necessarily.
DKIM2 isn’t designed to punish good senders.
It’s designed to expose bad ones.
If your email list is healthy…
If subscribers actually open your emails…
If your authentication is configured correctly…
You’re already ahead of the game.
The brands most at risk are the ones sending emails people no longer want.
DKIM2 simply makes that easier to detect.
How to prepare for DKIM2 today
The best time to fix deliverability problems…
Is before mailbox providers find them.
Start by checking:
✔ Is your domain properly authenticated?
✔ Are you emailing engaged subscribers?
✔ Is your sender reputation healthy?
✔ Are your emails landing in the inbox or the spam folder?
If you don’t know the answer…
Don’t guess. Test it.
👉 Run our free Email Deliverability Test
In less than two minutes, you’ll get a snapshot of your email health and identify potential deliverability issues before they affect your campaigns.
Where can I learn more about DKIM2?
Because DKIM2 is still under development, the most authoritative source is the official IETF Internet-Draft, which outlines the proposed specification and its technical objectives.
📖 DKIM2 Internet-Draft (IETF):
https://datatracker.ietf.org/doc/draft-ietf-dkim-dkim2-spec/