The Only Email Deliverability Checklist You’ll Ever Need

Emails are everywhere nowadays, right? Since COVID-19 hit, there are even more flying around. 

The 2026 sender rules: what changed and the numbers that matter

Updated July 2026. The Google/Yahoo requirements that landed in 2024 have hardened, and Microsoft joined the enforcement. If you send at volume, these are gates, not suggestions:

Requirement	The 2026 reality
Who it applies to	5,000+ emails/day/domain triggers bulk-sender rules at Google, Yahoo, and now Microsoft
Authentication	SPF + DKIM + DMARC required; DMARC at p=none is now a starting point, with providers expecting progression toward quarantine/reject
Spam rate	0.30% is the hard ceiling: at or above it, Gmail withholds delivery mitigation until you hold below it for 7 consecutive days. Manage to 0.10%
Unsubscribe	One-click (RFC 8058) required on promotional bulk mail, honored within 2 days, no login walls
The stakes	Compliant senders average ~89% inbox placement; non-compliant see 22-34% of mail routed to spam

The practical takeaway: authentication is a one-time setup, but the spam-rate ceiling is an ongoing behavior constraint. It is enforced against your domain, not your campaign, which means one bad list can tax every email your company sends. Verified addresses, warmed inboxes, and per-inbox pacing are how you stay under 0.10% by design rather than by luck.

But here’s the thing – with so many emails, it’s tough to make sure yours gets seen. 

In fact, 61% of salespeople and email pros say getting emails into inboxes is getting harder. (Source: Validity)

Therefore, a lot of folks are looking for quick tricks to dodge spam filters, but the truth is, there’s no easy fix. 

Instead, here’s an email deliverability checklist of best practices to troubleshoot potential issues.

We’ll cover this checklist in three categories and additionally, you will find answers to major deliverability questions that you’ve been pondering for all these days –

1. Email deliverability checklist

• Checks to do before sending emails
• Checks to do while sending emails
• Checks to do while writing emails

2. Assessing your current deliverability status

• How do I check email deliverability?
• How do you ensure email deliverability?
• How is email deliverability measured?
• What is a good email deliverability rate for emails?

3. Final thoughts

[Email Deliverability Checklist] 18 Deliverability checks to optimize your email deliverability

Before sending emails

1. Use secondary domains: Avoid using your primary domain for sending emails. Purchase secondary domains similar to your primary domain.
   1. Example: If your primary domain is google.com, purchase domains like – trygoogle.com, getgoogle.com, viewgoogle.com, google.co, google.org, etc.
   2. Invest in a dedicated IP for email marketing to reduce the risk of getting blacklisted.
2. Create multiple email accounts (3-5) per domain – either Google Workspace or Microsoft accounts, with variations of the same name.
   1. Example: Sundar pichai – sundar@trygoogle.com, sundarp@trygoogle.com, sundar.p@trygoogle.com
3. Authentication protocols: Set up SPF, DKIM, and DMARC for all sender email accounts.
4. Warm up your email account: Automatically warm up your email account before sending emails to your prospects. Start with 10-15 days of warming up, gradually increasing the sending volume from 20 to 50 emails per day.
   1. Purchase pre-warmed IP to send out your marketing emails.
      1. Note: This means IP is only warmed up, not your email account/ domain. You need to warm up your email account separately.
5. Create a high-quality email list: While creating lists from a data provider, make sure to filter for contacts or emails of the highest quality. Nearly all data providers offer this filtering feature.

While sending emails

6. Maintain email list hygiene by cleaning it regularly to exclude ‘catch-all emails’ and group emails like sales@google.com. Use tools like ZeroBounce to find invalid & fake email addresses and remove them consistently.
   1. A catch-all email account is a mailbox designed to receive emails sent to any invalid email address within a domain.
   2. For instance, if an email is directed to wxy.z@company.com instead of wxyz@company.com, it won’t bounce but will be routed to the catch-all mailbox.
7. Perform weekly & monthly domain quality checks to ensure your domain is not blacklisted using a tool like MXtoolbox.
8. Limit daily email sends: Send only between 50-200 emails per day per account to maintain sender reputation.
   1. If you’d like to send more than 200 emails, opt for multiple inboxes to increase the limit.
9. Choose optimal sending times: Midweek days are the best to send sales/ marketing emails for maximum engagement. However, this depends on your target audience as well.
   
   

While writing emails

10. Address prospect’s pain: List the top 3 pain points your business solves and use only them in your emails, from start to all the follow ups.
    1. Example:
       
       Gartners says, 40% of engineering time is spent on technical debts and that’s the reason feature releases are delayed by 90% of time. Is that something you’re also facing?
       
       Here’s how we helped xx reduce technical debts by 70% and helped them release 3x more features compared to previous year.
11. Avoid spam-triggering words such as ‘guarantee,’ ‘free,’  etc. to prevent emails from being flagged as spam.
12. Limit links: Do not include more than 2 links per email.
13. Limit email size: Email size shouldn’t exceed 100 KB for any type of email. 75 KB is just perfect.
14. Links for files: Leave out large attachments. Use Google Drive links if needed.
15. Minimize number of images: Use fewer images in emails to improve load times.
16. Don’t use calendar links within email; instead use a CTA as it initiates conversation.
    1. Once the prospect engages with you, subtly pass the link to book a meeting only if required.
    2. Pro tip: Let me know what time works for you. For your convenience I’m attaching my calendar link.
17. Keep your signature simple: Avoid adding unnecessary details like company names or website links.
18. Always include an unsubscribe link and regularly remove unsubscribed individuals from your email list.

Assessing your deliverability status

Now that you have an email deliverability checklist in hand, it’s essential to assess where you stand in terms of email deliverability. How can you tell if you’re already facing issues? 

Let’s start by asking some basic questions:

1. How do I check email deliverability?

You can check email deliverability using online tools like GlockApps or SendForensics, which simulate email delivery and provide detailed reports on inbox placement and potential issues. 

Additionally, it’s essential to have a tool like Salesgear where you can run campaigns, analyze engagement metrics, and monitor email deliverability all in one place.

2. How do you ensure email deliverability?

Make sure to have all the boxes ticked in the checklist above.

Follow best practices like maintaining a clean email list by regularly removing inactive or invalid addresses. 

Personalize emails to improve engagement, monitor key metrics like open and bounce rates, and use authentication protocols like SPF, DKIM, and DMARC to verify your sender identity and protect against spoofing.

3. How is email deliverability measured?

Email deliverability is measured by analyzing various metrics –

• Open rate
• Bounce rate
• Spam complaint rate – tracks how many recipients mark your emails as spam
• Inbox placement rate – gives the percentage of emails that land in recipients’ inboxes rather than spam folders

4. What is a good email deliverability rate for emails?

While there isn’t a one-size-fits-all answer, generally, a high inbox placement rate (the percentage of emails delivered to the inbox rather than the spam folder), low bounce and complaint rates are indicators of good email deliverability.

Answering these questions will help you analyze your current situation of deliverability.

Final thoughts

Ensuring your emails reach recipients’ inboxes is crucial. 

No matter how great your email content and subject line are, if your emails don’t land where they’re supposed to, all your efforts go to waste.

It’s important to realize that even big companies face deliverability challenges. While this email deliverability checklist provides valuable insights, it’s essential to approach email optimization with a realistic mindset.

Remember, optimizing email deliverability is not a one-time task. 

It’s an ongoing process that requires consistent attention and fine-tuning to achieve lasting success. 

So, stay proactive, use this email deliverability checklist, and keep refining your strategies to ensure your emails consistently reach their intended recipients.