Understand email deliverability basics

May 22, 2025

Overview

This guide explains what email deliverability means and what impacts it. If you're sending campaigns or automations through GROW, it’s important to understand how inboxes decide whether your message gets delivered — and where it ends up.

Inbox placement isn’t just about pressing “Send.” Deliverability depends on your email domain, your list quality, and how recipients engage with your messages. This article breaks it all down.

Prerequisites

Before you begin:

You must be using GROW to send marketing emails or automations
Your sending domain should be connected and verified in GROW
You should have basic familiarity with campaigns and email sends

Step 1: Know what deliverability really means

Deliverability is whether your emails land in the inbox, not just whether they were accepted by the recipient’s email server.

Delivered means it reached the mailbox system
Deliverability means it reached the actual inbox (not spam, promotions, or junk)

Inbox providers (like Gmail or Outlook) decide where your message goes based on:

Your sending domain reputation
Your IP reputation
The quality of your contact list
How people interact with your emails (opens, replies, spam complaints)
Image to text ratio in the email
ESPs often do not like full HTML emails

Tip: Email deliverability is outside of GROW’s control. GROW sends the emails, but inbox providers decide how they're handled.

Step 2: Understand inbox placement and why it's inconsistent

Inbox providers use complex algorithms to decide inbox placement. That means:

You can send the same email to two people, and one may see it in Inbox, the other in Promotions or Spam
Providers analyze things like:
- Previous engagement from that contact
- Their personal spam settings
- Your overall domain and content reputation
- Your email template. Does it have a healthy ratio of images to text as well as an unsubscribe link in the email?

Inbox placement is not guaranteed, even if emails are “delivered.”

Step 3: Know how your emails are sent through GROW

Emails sent through GROW are delivered via shared IP pools managed by the platform. Here’s what that means:

GROW controls the infrastructure (IP addresses, servers)
You control your content and contact list
Because the IP pool is shared, bad practices by one user could impact others — which is why GROW monitors IP pool health

Despite the shared pool, your domain reputation has the most impact on your deliverability.

Step 4: Focus on your domain reputation — it’s what matters most

Inbox providers track how your domain performs over time. If you build a bad rep, your emails may be blocked or spammed.

Your domain reputation is affected by:

Bounce rate (bad or fake emails)
Spam complaints
Low engagement (no opens/clicks)
Sending volume spikes
Sending to cold/unverified lists

Best practice tips are to:

Send to engaged, opted-in contacts
Avoiding cold lists or purchased email databases
Send value-based content that gets opens and clicks
Gradually increase your email volume, especially with a new domain
Ensure that there is an unsubscribe link in your email template
Ensure that your email template isn’t just made up of images or large columns of text

Step 5: Understand DNS records (SPF, DKIM, and DMARC)

Email authentication is critical for deliverability. GROW provides you with the DNS records you need — you just have to set them up.

Here’s what each one does:

SPF (Sender Policy Framework): Defines what IP addresses are allowed to send on your domain’s behalf
DKIM (DomainKeys Identified Mail): Adds a signature to each message to verify it wasn’t altered
DMARC: Tells inbox providers what to do if SPF or DKIM checks fail

Tip: You’ll get these records when connecting your email domain in GROW — publish them correctly in your domain’s DNS settings.

Step 6: Respect inbox placement boundaries

You can’t control inbox algorithms, but you can avoid common mistakes:

Don’t try to bypass spam filters — it won’t work
Don’t send to cold lists or scraped emails
Avoid sending the same email over and over
Don’t use aggressive language or misleading subject lines
Keep your unsubscribe link visible and functional
Send only to people who actually want to hear from you

Expected outcome

By following deliverability best practices and understanding how email systems work, you can improve the chances your messages land in your audience’s inbox — which helps drive engagement, conversions, and trust in your brand.

Troubleshooting / FAQs

Q: Can I trust the email statistics that GROW shows?

A: Yes, to a certain degree. iOS devices—especially since Apple’s Mail Privacy Protection (MPP) rollout—can significantly skew your email marketing stats. When users open emails in the Apple Mail app, MPP preloads email content (including tracking pixels) even if the user never actually reads it. This inflates open rates, making them unreliable. As a result, marketers should shift focus toward engagement metrics like clicks and conversions rather than opens to get a clearer picture of campaign performance.

Q: My email was “delivered” — why didn’t it land in the inbox?

A: Delivery just means the server accepted it. Inbox placement depends on your domain reputation, content, and the recipient’s inbox filters.

Q: Does GROW control inbox placement?

A: No. GROW manages the sending infrastructure, but inboxes (like Gmail or Outlook) decide where each message goes.

Q: How do I fix poor deliverability?

A: Clean your list, authenticate your domain, stop emailing inactive users, and send content that drives opens and replies.

Still need help?

Reach out to our support team via [email protected]