Do I need to add all my subdomains to Google Postmaster Tools?

Yes, it is highly recommended to add all subdomains you use for sending emails to Google Postmaster Tools. While verifying the root domain simplifies the process for subdomains, each subdomain develops its own sender reputation and needs to be monitored individually for optimal deliverability. This ensures you catch any issues specific to a particular email stream.

How long does it take for data to appear for a new subdomain?

The data in Google Postmaster Tools typically starts appearing within 24-48 hours after your domain or subdomain is successfully verified and begins sending email volume. However, meaningful trends and comprehensive data may take a few days or even a week to accumulate, especially for new sending subdomains that haven't built significant volume yet.

Does Postmaster Tools data cover G Suite domains?

Google Postmaster Tools primarily focuses on email sent to @gmail.com and @googlemail.com addresses. While G Suite (now Google Workspace ) domains use Gmail infrastructure, the data available in Postmaster Tools is primarily for consumer Gmail. For comprehensive insights on Workspace domains, you might need to rely on Workspace-specific reports or DMARC aggregate data .

Can multiple users access Postmaster Tools for a single domain?

Yes, multiple users can access Postmaster Tools for a single domain. The owner of a verified domain can invite others to view its dashboards. This is particularly useful for teams responsible for email deliverability, allowing different members to monitor performance and collaborate on issue resolution without sharing login credentials.

How do I set up Gmail Postmaster Tools for a domain with subdomains? - Tools - Email deliverability - Knowledge base

Gmail Postmaster Tools provides essential insights into your email sending performance, helping you maintain a healthy sender reputation and ensure your messages reach the inbox. If you send emails from a primary domain, like yourdomain.com, and also from subdomains such as mail.yourdomain.com or marketing.yourdomain.com, it's crucial to set up Postmaster Tools correctly for all of them. This ensures you have a comprehensive view of your email program's health across all sending identities.

Understanding how to properly configure Postmaster Tools for both your root domain and its subdomains is key to leveraging its full potential. This guide will walk you through the process, clarifying common questions about domain verification and data aggregation for subdomains.

Understanding Google Postmaster Tools and subdomains

Google Postmaster Tools is designed to provide senders with data on their email performance when sending to Gmail users. This includes metrics like spam rate, IP and domain reputation, delivery errors, and DMARC authentication status. Having access to this data is critical for any sender looking to optimize their email deliverability and avoid common pitfalls like being placed on a blocklist (or blacklist).

When it comes to subdomains, the setup often causes confusion. Many organizations use separate subdomains for different types of email, such as transactional.yourdomain.com for receipts and marketing.yourdomain.com for newsletters. This strategy helps isolate reputation, meaning a problem with marketing emails won't necessarily tank the deliverability of transactional messages. Gmail Postmaster Tools allows you to monitor each of these sending identities individually, but there are nuances to how the data is presented.

It's important to understand how Postmaster Tools handles subdomains in relation to the root domain. While you can add and monitor individual subdomains, the general consensus is that domain reputation metrics are not simply aggregated from subdomains up to the root. Each sending domain, whether root or subdomain, develops its own reputation based on its sending behavior. For a deeper dive, Google offers comprehensive documentation on Postmaster Tools setup.

Setting up your domain and subdomains

The first step to setting up Postmaster Tools for a domain with subdomains is to add your root domain. Go to the Gmail Postmaster Tools website and sign in with a Google account. Click the '+' button to add your primary domain, for example, yourdomain.com. Google will then prompt you to verify ownership of this domain, usually by adding a DNS TXT record to your domain's DNS settings.

After your root domain is verified, you can add any subdomains you use for sending. The key advantage of verifying the root domain first is that you won't need to re-verify each subdomain individually. Postmaster Tools assumes that if you control the root domain, you also control its subdomains, simplifying the setup process for multiple sending identities. This is important to remember, as it streamlines the entire process, preventing you from having to verify ownership of each subdomain via DNS.

The verification process involves adding a TXT record to your domain's DNS. This record typically looks like this:

Example DNS TXT record for domain verificationDNS

Host/Name: @ or yourdomain.com
Type: TXT
Value: google-site-verification=YOUR_UNIQUE_CODE

If you are setting up a specific subdomain without first verifying the root, you will need to add a similar TXT record for that subdomain specifically, like:

Example DNS TXT record for subdomain verificationDNS

Host/Name: mail.yourdomain.com
Type: TXT
Value: google-site-verification=YOUR_UNIQUE_CODE

Once the DNS record is published, return to Postmaster Tools and click Verify. It might take some time for DNS changes to propagate, so be patient. For more details on the verification process, see our guide on how to verify a domain in Postmaster Tools.

Important consideration

The domain that Postmaster Tools asks you to add (and consequently verify) should be the domain that is used for authentication. This is typically the domain in your DKIM d= tag or the domain from your SPF record. If your subdomains are authenticating independently, you should add them to Postmaster Tools to get specific data for each.

Interpreting Postmaster Tools dashboards

After setting up your domains and subdomains, Postmaster Tools will begin collecting data. This can take a few days, depending on your email volume. The most crucial dashboards to monitor are:

Spam rate: Shows the percentage of emails marked as spam by users and Google's spam filters.
IP reputation: Reflects the reputation of the IPs sending email from your domain.
Domain reputation: Indicates Gmail's trust in your sending domain. This can be Bad, Low, Medium, or High. A Bad reputation means many emails will be rejected or marked as spam. Conversely, High indicates excellent deliverability.
Feedback loop (FBL): Provides data on user spam complaints for senders who have implemented a Gmail FBL.
Authentication: Details the percentage of emails that passed SPF, DKIM, and DMARC authentication. This is crucial for verifying email authenticity and preventing spoofing.

For subdomains, you will observe separate data for each. For instance, transactional.yourdomain.com might have a High reputation, while marketing.yourdomain.com could be Medium. This separation allows for granular monitoring and troubleshooting. It emphasizes the need to actively manage the sending practices of each subdomain to maintain optimal deliverability.

Understanding these metrics is vital for diagnosing and resolving email deliverability issues. For example, a sudden drop in domain reputation or an increase in spam rate on a specific subdomain would immediately alert you to a problem with that particular sending stream, allowing for targeted intervention.

Leveraging Postmaster Tools for deliverability

Monitoring your Postmaster Tools dashboards should be a continuous process. If you notice a decline in your reputation or an increase in spam complaints, it's time to investigate. Common causes include sending to invalid email addresses, low engagement, or users marking your emails as spam. By identifying these issues early, you can take corrective action before they severely impact your deliverability.

A key component of maintaining strong email deliverability, especially when using subdomains, is robust email authentication. Ensure that your SPF, DKIM, and DMARC records are correctly configured for all sending domains and subdomains. Misconfigurations in these areas are common reasons for emails landing in the spam folder or being rejected outright. Regularly review your authentication setup to ensure proper alignment and prevent spoofing attempts, which can severely damage your sender reputation.

If you find your domain or IP addresses listed on a public blocklist (or blacklist), Postmaster Tools can help you understand the impact on Gmail deliverability. While Postmaster Tools doesn't tell you which specific blocklist you're on, a sudden drop in IP or domain reputation often correlates with such listings. Proactive blocklist monitoring and prompt delisting requests are essential steps to recover your sender reputation and ensure your emails reach recipients.

Leveraging DMARC monitoring tools in conjunction with Postmaster Tools is also highly recommended. DMARC reports provide granular data on authentication failures, which can often explain why certain email streams are experiencing deliverability issues. This combined approach gives you a holistic view of your email ecosystem.

Maximizing your email deliverability

Setting up Gmail Postmaster Tools for your root domain and its subdomains is a foundational step toward achieving excellent email deliverability. By actively monitoring the dashboards and taking prompt action on any issues, you can maintain a strong sender reputation and ensure your messages consistently land in the inbox.

It's an ongoing commitment, but the insights gained from Postmaster Tools are invaluable for optimizing your email program and building trust with recipients. Remember, a healthy sender reputation translates directly to better engagement and higher ROI from your email marketing and transactional communications.

Views from the trenches

Best practices

Always verify your root domain in Postmaster Tools before adding subdomains to simplify the process and avoid repetitive DNS verification steps.

Implement robust SPF, DKIM, and DMARC authentication for all sending domains and subdomains to build trust with Gmail and ensure message authenticity.

Regularly monitor all Postmaster Tools dashboards for each sending domain, paying close attention to spam rates and domain reputation.

Common pitfalls

Neglecting to add subdomains to Postmaster Tools, which leaves blind spots in your overall email deliverability monitoring.

Failing to address authentication failures (SPF, DKIM, DMARC) identified in Postmaster Tools, leading to decreased inbox placement and potential blacklisting.

Ignoring low or bad reputation scores in Postmaster Tools, which can result in emails consistently landing in spam folders or being outright rejected.

Expert tips

I advise setting up alerts for significant changes in Postmaster Tools metrics, such as a sudden spike in spam complaints or a drop in domain reputation, to enable quick response.

You should cross-reference Postmaster Tools data with your DMARC reports to get a more granular understanding of authentication failures and their impact on deliverability.

For large organizations, I recommend creating a dedicated Google account for Postmaster Tools access that can be shared among deliverability team members to ensure continuity and collaborative monitoring.

Expert view

Expert from Email Geeks says that the domain to set up in Postmaster Tools should be the one authenticated via SPF or DKIM, which would likely be the subdomain used for sending.

2021-03-02 - Email Geeks

Expert view

Expert from Email Geeks explains that the domain (subdomain or parent) used in the DKIM d= tag is the one that needs to be added to Postmaster Tools.

2021-03-02 - Email Geeks