Professionals in Customer Success and Customer/Employee Experience often rely on email surveys and campaigns to engage their audience. However, improper emailing practices can harm your sending domain’s reputation – meaning your messages could start landing in spam folders or be blocked entirely.
Key Overview - Follow these steps when sending emails:
Send emails only to people who have given permission
Keep Your Mailing List Clean (List Hygiene)
You are required to include an Unsubscribe Option (and Honor It)
Avoid Spam-Like Content and Design
Use a Recognizable Sender Name and Subject Line
Send at a Steady Pace and Reasonable Volume
Why Domain Reputation Matters
Domain reputation is essentially your domain’s email “credit score” with mailbox providers. Services like Gmail and Outlook keep track of how people react to emails from your domain (opens, deletions, spam reports, etc.) and whether you follow proper sending practices. A good reputation means providers trust your emails and deliver them to inboxes. A bad reputation means your emails are more likely to be flagged as spam or even outright rejected. In extreme cases, a poor sender reputation can get your domain blacklisted, making it nearly impossible for any of your emails to reach recipients. In short, protecting your sending domain’s reputation is critical to successful email outreach.
Even if you have valuable content, it won’t matter if your emails never reach the intended audience. Following compliance and best practices keeps your domain trusted so your messages land in inboxes rather than spam folders.
Build a Permission-Based Email List
One of the most important steps is to send emails only to people who have given permission or expect to hear from you. This ensures recipients are more likely to engage and less likely to mark your messages as spam.
Use Opt-In Contacts Only: Always obtain consent before emailing someone. This could be through sign-ups, customer agreements, or prior relationships. Avoid emailing cold contacts who never agreed to receive your communications. Unsolicited emails often lead to complaints and hurt your reputation.
Never Buy Email Lists: Purchased or scraped lists contain people who don’t know your company. These recipients are more likely to ignore or report your emails. Using such lists can quickly damage your domain’s standing (and it may violate anti-spam laws). Build your list organically, even if it grows slower – quality is more important than quantity.
Consider Double Opt-In: Implementing a double opt-in (where users confirm their email address by clicking a link after subscribing) can further ensure everyone on your list truly wants your emails. This extra step filters out fake or misspelled addresses and confirms the recipient’s interest. While not mandatory, it can significantly improve list quality and protect you from sending to invalid addresses.
By emailing only those who want to hear from you, you’ll get better engagement and far fewer spam complaints. Engaged recipients opening and clicking your emails send positive signals to mailbox providers that your domain is trustworthy.
Keep Your Mailing List Clean (List Hygiene)
Even with a permission-based list, over time some addresses become problematic – people change jobs, abandon emails, or lose interest. Regular list maintenance (often called “list hygiene”) is crucial for deliverability:
Remove Invalid or Bouncing Addresses: If an email address consistently bounces (e.g. “user not found”), stop sending to it. Continuing to send to bad addresses causes high bounce rates, which email providers see as a red flag. High bounce rates can make it look like you’re blasting out emails without regard for validity (often what spammers do).
Suppress Inactive Recipients: Identify recipients who haven’t engaged with your emails in a long time (for example, no opens or clicks in 6-12 months). It may be best to stop emailing them or at least email them less frequently. Inactive emails can turn into spam traps or simply drag down your engagement metrics. Mailbox providers notice if most people ignore your messages. By removing or sunsetting unengaged contacts, you improve your overall open rate and reduce the chance of hitting a recycled spam trap address.
Update and Validate Regularly: Make it a habit to clean your list periodically. Some organizations validate emails (using tools or services) to catch typos or dead accounts before a big send. At minimum, use your platform’s reporting to periodically prune out addresses with repeated bounces or those who never engage. A smaller list of genuinely interested recipients is far better than a huge list full of dead weight.
Keeping your list clean protects your domain’s reputation by showing email providers that you send to real, active people. It also saves you money and effort by not sending emails to addresses that will never respond.
Always Include an Unsubscribe Option (and Honor It)
Every bulk or marketing email must include a clear way for the recipient to opt out (unsubscribe) from future emails. This isn’t just a best practice – it’s often a legal requirement and a key trust factor for email providers.
Clear Unsubscribe Link in Every Email: Ensure that your emails (newsletters, survey invites, promotions, etc.) have an unsubscribe link that is easy to find, typically in the footer. Wording like “Unsubscribe” or “Manage email preferences” should be plainly visible – don’t hide it in a wall of text. Services like Gmail and Outlook may even look for a list-unsubscribe option and will assist users in opting out if it’s present. If they don’t see an obvious unsubscribe, recipients might hit the “Report Spam” button instead, which is much worse for your domain reputation.
Honour Unsubscribes Promptly: The moment someone opts out, stop emailing them. Good practice is to process unsubscribe requests immediately (or within a couple of days at most). Many laws (like the U.S. CAN-SPAM Act) mandate that you honor opt-outs within a certain timeframe (e.g. 10 business days in the U.S.). Quick removal protects your brand – sending emails to someone who has unsubscribed not only annoys them (increasing the chance they report you), but can also violate compliance rules.
No Unsubscribe Needed for One-to-One or Transactional Emails: Note that for truly transactional emails (like a password reset or an individual customer support response), an unsubscribe link isn’t required. But if you’re sending bulk surveys or marketing content through your SaaS platform, always include the opt-out. When in doubt, it’s safer to include an unsubscribe option even in mass internal communications, just to give employees an option to opt out of non-essential mailings.
Providing an easy escape route for recipients might sound counter-intuitive, but it keeps your list healthy and your recipients happier. It’s far better for someone to voluntarily leave your list than to have them frustrated and flag your email as spam. Email providers reward senders who respect user choices, and your domain will maintain a better reputation as a result.
Use a Recognizable Sender Name and Subject Line
People are more likely to trust and engage with emails that look legitimate and familiar. By setting a clear sender identity and honest subject lines, you reduce the chances of being mistaken for spam or phishing.
Identify Yourself Clearly: Use a sender name and email address that recipients will recognize as your company or organization. For example, an email could come from “Acme Inc. Surveys [email protected]” or “Jane from Acme Support [email protected]”. Avoid obscure addresses or just a raw email without a friendly name. If possible, avoid using a no-reply address altogether – an email that allows replies (and is monitored) appears more trustworthy and encourages two-way communication. At the very least, ensure the “From” address is valid (exists and can receive mail). A valid reply-to address is actually one of Outlook’s recommended best practices, because it confirms there’s a real sender on the other end.
Accurate, Non-Deceptive Subject Lines: Your subject line should clearly reflect the content of the email. Don’t use misleading or “clickbait” subjects just to trick people into opening (“Re: Your account” when it’s not a reply, or overhyped claims unrelated to the email content). Misleading subjects not only frustrate readers but can also violate laws (CAN-SPAM requires truthful subject lines). Plus, email filters are smart – they can penalize emails with subject lines that look intentionally deceptive.
Avoid Spammy Language and Formatting: Certain subject line styles scream “spam” to filters. For instance, AVOID ALL CAPS, excessive exclamation points!!!, or phrases like “$$$ MAKE MONEY NOW!!!” in your subjects or body. These are classic spam signs. Instead, keep your subject professional, concise, and relevant (e.g. “We value your feedback – Acme Customer Experience Survey”). A good rule of thumb: if it looks like something you would consider junk mail, don’t send it.
Using a consistent sender name and a clear subject line builds trust. When recipients recognize your emails at a glance, they’re more likely to open them and less likely to mark them as spam. And when mailbox providers see good open rates and low complaints for your domain, they’ll continue delivering your messages to inboxes.
Avoid Spam-Like Content and Design
Beyond the subject line, the content and design of your email can either help or hurt its chances of reaching the inbox. Spam filters look at the actual email content and layout for red flags. Keep your emails reader-friendly and spam-filter-friendly with these tips:
Keep a Good Text-to-Image Ratio: Don’t send emails that are just one big image or banner. Image-only emails (or emails with very little text) are often used by spammers to bypass text-based filters. Aim for a healthy balance – for example, at least 50-60% of your email content should be text. Include a plain text section if you’re sending fancy HTML. This makes your message more trustworthy to filters and also readable for those who block images by default.
Be Mindful of Keywords and Tone: Words and phrases like “Free!!!”, “Act Now!!!”, “Earn $$$”, or overly promotional language can trigger spam filters, especially when combined with other factors. You don’t have to avoid every marketing term, but try to sound natural and sincere, not overly salesy or sensational. Also steer clear of obscure fonts or rainbow text colors – those gimmicks often accompany spam. Keep your font standard and legible.
Limit Attachments and Links: If you’re sending a survey or newsletter, it’s usually best to include a link for the user to click (to take the survey, read more, etc.) rather than attaching files to a bulk email. Attachments (especially .zip or .exe files) from mass senders can look suspicious and may get blocked by security filters. Only attach files if absolutely necessary and if they’re expected by the recipient. Similarly, don’t cram your email with dozens of links – a high link-to-text ratio can look spammy. Include necessary links, but make sure each has a clear purpose and label.
Avoid URL Shorteners and Strange Domains: Using URL shorteners like bit.ly or tinyurl in bulk emails can raise red flags. Spammers often hide malicious links behind shorteners. Instead, use the full URL or a branded link that clearly shows your domain (e.g. “survey.acme.com/feedback” looks more trustworthy than a random shortened URL). Likewise, any links you include should ideally go to reputable domains (preferably your own website or known sites). If you link to third-party content, make sure those sites aren’t known for spam.
Design for Clarity, Not Gimmicks: Fancy scripts or forms embedded in the email, multiple different fonts, or an overload of images might not just irritate readers – they can also trigger filters. Keep your email layout clean and professional. Ensure it’s mobile-friendly and accessible. A well-designed, simple email with a clear call-to-action will not only pass through filters more easily but also provide a better experience for your recipients.
In short, look like a legitimate sender, not a spammer. By avoiding the common hallmarks of spammy emails, you reduce the risk of tripping content-based filters. Focus on making your message clear, valuable, and easy to read. Not only will this help deliverability, but it also boosts engagement, since recipients appreciate clear and relevant content.
Send at a Steady Pace and Reasonable Volume
How you send emails (in terms of timing and volume) can impact your domain’s reputation. Sudden or irregular sending patterns can appear suspicious to email providers. Follow these best practices for sending behavior:
Avoid Sudden Spikes in Volume: If you’re new to sending or haven’t emailed your list in a long time, don’t start by blasting thousands of emails at once out of the blue. Large, abrupt spikes in sending volume can alarm spam filters, which might throttle or flag your emails. Instead, gradually increase your sending volume – a process often called “warming up” your domain or IP. For example, start with a smaller batch of emails on day one, then a larger batch on day two, and so on. This gradual ramp-up shows providers that you’re a consistent sender, not a spam operation that just popped up.
Maintain a Consistent Schedule: Try to send emails at regular intervals rather than very sporadically. Consistency helps build a predictable sender reputation. For instance, if you send a monthly newsletter, try to send it around the same time each month. If you run weekly campaigns, keep them on a regular day/time as much as possible. ISPs notice patterns – a consistent pattern is generally seen as normal behavior, whereas erratic patterns may draw scrutiny.
Don’t Overwhelm Your Recipients: Apart from technical volume, consider the human element – sending too many emails to the same people in a short period can lead to annoyance and higher unsubscribe or spam-report rates. Find a sensible frequency that keeps your audience informed but not irritated. For example, if you have a survey program, you might not want to email the same customer more than once in a week or month about feedback (unless they expect a series). Over-mailing can cause recipients to disengage or mark your messages as spam, which in turn hurts your domain reputation.
Stagger Send Times (If Possible): This is a minor point, but if you have the capability, consider avoiding sending your emails at exact common times (like on the hour or half-hour) when many other companies send their blasts. Sometimes, a huge glut of emails hitting at once can trigger rate limiting at the receiving end. Sending at an off-peak or irregular time (e.g. 10:13 AM instead of 10:00 AM) might help your emails stand out in the inbox and avoid potential bottlenecks. This is not critical, but it’s a small optimization some senders use.
By controlling your sending pace and volume, you present yourself as a reliable sender rather than a potential spammer. Mailbox providers give favorable treatment to domains that send a steady volume of mail with good engagement, as opposed to those that send huge blasts inconsistently. Remember, slow and steady wins the race when it comes to building a solid sender reputation.
Monitor Engagement and Feedback
While this article avoids technical setup, one proactive practice is to keep an eye on how recipients and email providers are reacting to your emails. Monitoring certain metrics and feedback can alert you to problems before they escalate:
Track Key Email Metrics: Pay attention to your email open rates, click-through rates, bounce rates, and unsubscribe rates on each campaign. A sudden drop in opens or spike in bounces/complaints is a warning sign. For instance, if a particular email had many people mark it as spam (some email platforms report this as “abuse complaints” or feedback loop reports), take that seriously. It means the content or targeting of that email was unwelcome, and continuing down that path could get your domain flagged.
Use Tools Provided by Email Services: Services like Google’s Postmaster Tools and Microsoft’s SNDS (Smart Network Data Services) can give insight into your domain’s reputation and spam rate as seen by those providers. Setting these up typically requires some IT assistance (and DNS verification), but even non-technical teams can benefit from the reports once configured. If available, periodically review these to ensure Gmail, Outlook, etc., are rating your domain as healthy. They can show data like spam complaint rates, which should be kept extremely low (Gmail, for example, expects a complaint rate under 0.1% for bulk senders).
Keep an Ear Out for Blocks or Issues: If customers or colleagues say they aren’t receiving your emails, investigate promptly. Sometimes you may discover that your domain or IP was temporarily blocked by an email provider due to a reputational issue. Also, some email service providers (ESPs) will notify you if your campaigns are getting high bounce or complaint rates. Don’t ignore those alerts. If you do get blocklisted or see a big deliverability drop, you may need to pause and diagnose the cause (perhaps send volume, content, or a bad list segment) and possibly reach out to your ESP support for guidance.
Test and Preview Your Emails: It can be helpful to test-send your email to a few accounts (e.g., a personal Gmail, Outlook.com, Yahoo account) before a big launch. See if the email lands in Inbox or Spam. While one test isn’t conclusive, it might catch obvious issues (like a broken unsubscribe link or a subject line that consistently goes to spam). Some organizations also use third-party inbox placement testing services, but even basic in-house testing is better than nothing.
Listen to Your Recipients: Finally, if you receive direct feedback from recipients (through replies or surveys about your emails), use that to adjust. If people say they’re getting too many emails or certain content is not useful, consider refining your approach. Happier recipients = better engagement, and better engagement = improved sender reputation.
Monitoring isn’t about obsessing over every single email, but about being aware of trends. If you notice trouble brewing (like declining deliverability or rising complaints), you can take action to fix your practices before your domain reputation is severely harmed. It’s much easier to maintain a good reputation than to recover from a bad one, so a bit of attentiveness goes a long way.
What Happens If You Neglect Best Practices?
Failing to follow these email best practices can have serious consequences. To underscore why all of this matters, here are some of the risks of poor sending behavior and non-compliance:
Emails Landing in Spam: The most immediate consequence is that your messages start skipping the inbox and get dumped in spam folders. If you’re noticing a drop in responses, it could be because most recipients never see your email. Once you’re identified as a habitual spam-folder candidate, it takes time and effort to regain inbox placement.
Domain or IP Blacklisting: Repeated bad practices (high spam complaints, sending to bad addresses, no unsubscribe, etc.) can lead to your sending servers or domain being blacklisted by major anti-spam organizations. If that happens, all emails from your domain may be blocked until you resolve the issue and appeal the listing. Being blacklisted is essentially a halt to your email program – your messages will bounce or be refused until the block is lifted, which can severely disrupt business operations.
Reputation Damage Can Spill Over: A damaged sending reputation doesn’t just affect marketing emails or surveys. It can also impact transactional or one-to-one emails from your domain. For example, if your domain gets a bad rep, even a password reset email or an important notification to a client might end up filtered out. Thus, a poor reputation can cripple both your marketing efforts and critical customer communications.
Provider and Legal Penalties: Large email providers (Microsoft, Google, Yahoo, etc.) are increasingly enforcing strict standards. They may rate-limit (slow down) your emails, impose temporary blocks, or in some cases permanently refuse email from your domain if you’re caught ignoring their guidelines. On the legal side, ignoring laws like CAN-SPAM or GDPR can lead to formal warnings or fines. For instance, not including an unsubscribe or continuing to email people who opted out can result in hefty penalties in some jurisdictions. In short, bad email practices can cost you financially and legally, not just in deliverability.
Loss of Customer Trust and Business Opportunities: Think of the customer experience – if your emails often wind up in spam, customers might miss surveys or important updates, leading to frustration. They may start to see your brand as unprofessional or untrustworthy. Moreover, if emails aren’t reaching the inbox, your team is missing chances to gather feedback or drive engagement. This can quietly erode the success of your customer success initiatives. Additionally, once a customer marks you as spam, it’s very hard to win them back; you might lose that line of communication permanently.
Recovery is Slow and Difficult: Unfortunately, there’s no quick fix for a trashed sender reputation. If you find yourself in a bad spot (lots of emails in spam or a blacklisted domain), it can take weeks or months of corrected behavior to repair the damage. During that time, you may have to send at lower volumes, change IPs or domains, and prove to providers that you’ve changed your ways. It’s a costly, time-consuming process. Thus, it’s far better to prevent problems by adhering to best practices from the start, rather than having to triage a deliverability crisis later.
In summary, neglecting proper email sending practices can severely limit your ability to reach and engage your audience. The risks range from short-term setbacks (emails going unseen) to long-term fallout (domain being un-sendable). For professionals in Customer Success and Experience roles, these outcomes can directly undermine your goals of customer engagement and satisfaction. It’s simply not worth cutting corners on compliance or quality – the price is too high.
Conclusion
Protecting your sending domain’s reputation is both an art and a science, but it fundamentally comes down to respect for your recipients and adherence to established rules. By building a quality opt-in list, keeping that list clean, including required opt-out options, sending relevant content at a reasonable pace, and monitoring the results, you create a virtuous cycle: recipients engage positively, and mailbox providers continue delivering your emails to them.
These best practices don’t require deep technical knowledge – they’re mostly about common-sense, ethical marketing and communication behavior. As a Customer Success or Experience professional, following these guidelines will help ensure your important emails – whether they’re customer feedback surveys, newsletters, or employee engagement notes – actually reach the people they’re meant for. You’ll safeguard the reputation of your company’s domain, maintain the trust of email services like Microsoft and Google, and ultimately achieve better outcomes from your email campaigns.
Remember, email deliverability is a privilege that’s earned. By treating recipients with respect (only emailing those who want it, and making it easy for them to opt out) and by sending content that adds value without tripping spam alarms, you’ll keep that privilege intact. Your sending domain will remain in good standing, and your emails will consistently land where they belong: in the inbox, ready to be read.