Every time you send an email, mailbox providers like Gmail, Yahoo, and Microsoft take note of your sending domain, authentication, how many valid recipient addresses you sent to, how many recipients engage with your email, your sending schedule, and many other factors, all of which contribute to your domain’s sending reputation, which is uniquely determined by each mailbox provider.
The more positive your reputation, the better your chances are at landing in recipient’s inboxes. A negative reputation, on the other hand, can lead to spam placement, throttling, or bounces.
If you’re part of a multi-team operation (like a franchise, university, or nonprofit chapter) it’s important to know that everyone sending from your domain shares reputation, regardless of the platform they send emails from. This is why optimizing best practices is so important: they protect the shared domain reputation that your whole organization depends on to reach the inboxes of your customers, community members, and donors.
Some factors that influence your sender reputation
- Authentication: SPF, DKIM, and DMARC are requirements for all major MBPs because they confirm your identity and allow your email platform to send on your behalf.
- List health: A healthy list consists of quality contacts. Valid addresses of double opt-ed in subscribers who are genuinely interested in receiving your emails, leads to more engagement with your emails (opens, clicks, etc.), which positively impacts your domain’s sending reputation. The opposite is also true: when subscribers consistently leave your emails unopened or don’t engage with your links, that can negatively affect your reputation. Subscribers reporting your emails as spam is also detrimental, since it signals to the mailbox provider that people aren’t expecting or interested in what you’re sending.
- Sending patterns: Not only do mailbox providers note how consistent or inconsistent you are with send frequency, volume of mail sent, and the domain you use, but your subscribers do too. Consistency builds a positive sender reputation and encourages more engagement from subscribers.
Ensure you’re authenticated
Before list hygiene or sending habits can move the needle, you need authentication (SPF, DKIM, and DMARC) in place for your sending domain. As mentioned above, authentication tells mailbox providers that you’re who you say you are and that you’ve granted permission for your email platform to send on behalf of your domain.
Authentication is also required by major mailbox providers. Gmail, Yahoo, and Comcast started enforcing authentication requirements for bulk senders in February 2024, and Microsoft followed suit in May 2025. Lack of authentication often results in bounces and can damage your reputation. It’s important for all senders, but it’s non-negotiable if you send 5,000 or more emails per day.
If you’re not sure where your authentication stands, contact your IT team or email platform partner for help.
Keep your lists healthy
Sending to an engaged subscribers and maintaining a quality list, is vital for positive sender reputation, which ties directly to reaching more inboxes. Invalid addresses and un-engaged subscribers, especially in large numbers, can hurt your reputation. Mailbox providers heavily weigh how engaged or un-engaged your recipients are when determining if your emails are wanted, which can affect inbox placement for everyone sending from your domain.
Email lists aren’t evergreen; permission to send to people fades with time, people change jobs and addresses, lose interest in your organization’s area of focus, or simply become too busy to engage. So maintaining and improving list hygiene works best as an ongoing habit, not something you do once and forget.
There are two practical places to focus when auditing your list health: start by ensuring that new contacts come onto your list cleanly, and removing existing subscribers who can hurt your sending reputation.
1. Verify new subscriber addresses
Keeping a list clean starts at the point of entry. Confirmed opt-in, sometimes called double opt-in, is the leading standard. When someone submits a form, they receive a confirmation email with a link they’ll click to verify their interest in receiving updates from you. That extra step helps filter out typos, fake addresses, spambots, and anyone who wasn’t serious about subscribing.
If you work with an existing or imported list, running it through an address verification tool before you send is a simple way to catch invalid contacts before they affect your reputation. And if multiple teams collect contacts through separate forms and processes, it’s worth ensuring everyone follows the same list standards.
2. Remove addresses that can damage your reputation
Some contacts on your list may be doing more harm than good if you continue to email them despite warning signs of un-engagement or delivery issues. Keep an eye out for these signals, consistently auditing your list, and don’t be afraid to remove subscribers when it’s time:
Inactive subscribers: Subscribers with no opens or clicks in the last 180 days or more are very unlikely to re-engage with your emails, so continuing to email them isn’t beneficial. Removing inactive subscribers will improve your mailing stats and show mailbox providers that you’re focused on sending to engaged subscribers, both of which help build and maintain a positive sender reputation.
Previously active subscribers: For subscribers who were engaged with your emails within the last 90-180 days, then dropped to inactive status, you can try sending them a re-engagement campaign. Any subscriber who re-engages can remain on your list; those who don’t should be removed. Honing in on your most engaged subscribers is always a beneficial and recommended best practice.
Subscriber addresses that hard bounce: These are permanent delivery failures. Remove the hard bounced addresses immediately and do not reattempt contact. Continuing to send to hard-bounced addresses indicates to mailbox providers that you’re not managing your list, and it harms your reputation. To help you avoid that, Emma automatically handles removing bad addresses for you. This can also help lower your overall bounce rates, which should be under 3% per send.
List size is the easiest number to track, but raw subscriber count doesn’t tell you how robust your program is or how subscribers are actually responding. A holistic view of opens, clicks, conversions, and segmentation patterns are better indicators, showing you who’s engaging, what resonates, and where your growth opportunities are.
Prioritizing this holistic view of list hygiene from shift focus from cleanup to clarity: removing un-engaged contacts sharpens your metrics, strengthens your reputation, and ensures the subscribers who genuinely want to hear from you get the best experience. That mindset is what separates teams that just send emails from teams that build successful email programs, and it’s exactly where Emma’s segmentation and reporting tools help you find meaningful patterns and grow a targeted, intentional list.
Build consistent sending patterns
Both mailbox providers and subscribers like consistency. When multiple teams send under the same domain, consistent sending patterns are essential to keeping your shared reputation healthy.
Avoid sudden spikes in how often you send or how many people you send to. You should also be careful not to change your sending domain without thorough guidance and consideration. Any large changes to your sending patterns can be interpreted by mailbox providers as spammer-like behavior, which can trigger automatic filtering or bounces and put your reputation in question.
If you’re planning big changes to your email program, we suggest contacting your email platform’s Support team for advice. Customized guidance from deliverability experts can also help ensure your changes and important sending seasons go smoothly.
Beyond mailbox providers, subscribers like to know when to expect your emails. In this ever changing world, you can give your subscribers the gift of consistency with pre-scheduled campaigns that are sent at a regular cadence. This will help with long term engagement, benefiting your reputation and therefore helping you earn inbox placement.
Improve your sending program with Emma’s tools
When many teams send from one domain, shared reputation is only as strong as the least careful sender: a single team with an unmaintained list or inconsistent habits can affect inbox placement for the whole organization. A platform with tiered accounts for distributed email marketing makes this manageable, giving you one view of every team (subaccount) and the tools to keep everyone aligned.
Optimizing your organization’s sender reputation across multiple teams can be a lot to manage, but Emma can partner with you to help. The Emma team can dig into your authentication setup, advise on list hygiene across subaccounts, and help everyone develop the sending habits that protect your shared reputation, ensuring your organization is getting the most out of their email sends.
Request a demo to see how Emma can support your organization’s email marketing →
