Gmail’s top 10 sender issues: what senders need to know

Gmail’s top 10 sender issues: what senders need to know

In 2023, Gmail introduced a list of sender requirements that all bulk senders are expected to follow. Google also published its “Top 10 Sender Issues” with recommendations to help improve email delivery and inbox placement.

Let’s break down the list and what it means for senders.

Gmail’s 10 sender requirements

1. Authenticate your outgoing mail

Gmail starts with the basics: authentication.

Before sending bulk email, make sure you have properly configured:

• SPF (Sender Policy Framework)

• DKIM (DomainKeys Identified Mail)

• DMARC (Domain-based Message Authentication, Reporting, and Conformance)

Without authentication in place, mailbox providers have no reliable way to verify that your mail is legitimate.

2. Respect user choice

It’s easy to forget that every marketing email lands in the inbox of an actual person. Pay attention to what subscribers truly want to receive: both in terms of content and frequency.

One recommendation I often make is simple: subscribe to your own email program.

Ask yourself:

• Are you receiving the type of content you expected?

• Are you sending too frequently?

• Would you stay subscribed if you were the customer?

We previously wrote about this concept in our blog on “Wearing Your Subscriber’s Shoes.”

3. Use Google Postmaster Tools

If you send mail to Gmail users, setting up Google Postmaster Tools is essential.

It provides visibility into:

• Domain reputation

• IP reputation

• Spam complaint rates

• Delivery errors

• Authentication compliance

You’ll also be able to see whether your sending domain is meeting Gmail’s sender requirements.

4. Monitor spam rates

Google recommends keeping spam complaint rates below 0.1%.

If recipients consistently mark your emails as spam, Gmail may begin classifying more of your mail as spam as well.

One important thing to understand: recovery takes time. Even if your spam rate drops back below 0.1%, inbox placement does not usually improve overnight. Reputation rebuilding is gradual and requires consistent sending behavior.

5. Ramp up sending volume slowly

Increasing sending volume too quickly can trigger temporary delivery issues and deferrals from Gmail.

Google recommends the following process when deferrals occur:

1. Pause sending for 15 minutes.

2. Resume by sending a single email message.

3. If successful, send below the original deferred volume for 24 hours.

4. After 24 hours without deferrals, increase daily volume gradually - around 25% per day.

5. Continue monitoring Google Postmaster Tools for domain or IP related throttling signals.

A slow, controlled ramp-up is especially important for new domains and IPs that are still establishing sender reputation.

6. Maintain consistent sending volume

The “batch-and-blast” approach is no longer effective.

Google recommends pacing email traffic evenly throughout the day and distributing campaigns over multiple days whenever possible. Sudden volume spikes can create reputation concerns, particularly for newer sending domains.

Even after a domain is fully warmed up, consistency still matters.

7. Avoid misleading subject lines and display names

Spammers often rely on deceptive tactics such as:

• Adding “Re:” or “Fwd:” to subject lines

• Using misleading display names

• Including emojis or visual tricks that imitate verified senders

Legitimate senders should avoid these tactics entirely. If it resembles spam behavior, it can negatively impact both trust and deliverability.

8. Limit sharing of IP addresses and domains

If you are sending from shared IP addresses or domains, your sender reputation is partially dependent on the behavior of other senders.

Using dedicated infrastructure gives you significantly more control over your reputation and deliverability performance.

9. Don’t spoof

Spoofing occurs when a sender disguises their identity in an attempt to trick recipients into opening an email.

This can include:

• Fake display names

• Misleading sender addresses

• Impersonation tactics

10. Go to the source

Google’s Help Center contains valuable guidance on:

• Sender requirements

• Authentication standards

• Deliverability best practices

• Troubleshooting recommendations

It’s worth checking regularly to stay current on changes that could impact your email program.

Final thoughts

Gmail’s latest guidance reinforces a broader trend in email deliverability: mailbox providers increasingly reward senders who prioritize authentication, consistency, transparency, and subscriber experience.

If your email program is struggling with any of the issues above - or if your Google Postmaster metrics aren’t where they should be - it may be time to reevaluate your sending practices.

Our professional services team can help identify deliverability issues and recommend changes to improve inbox placement and overall email performance.