--- title: Why is my Domain Being Flagged as Spam? description: Just one reported message can impact your spam rating.  In this article, learn the top factors that affect email deliverability & domain reputation. image: https://blog.fivenines.com/hubfs/Blog%20Feature%20Images/122023_DomainFlaggedAsSpam.png --- [Skip to the main content.](https://blog.fivenines.com/domain-being-flagged-as-spam#main-content) 1-855-817-5959    [help@fivenines.com](mailto:help@fivenines.com) [![FN\_Reverse\_Logo](https://blog.fivenines.com/hs-fs/hubfs/FN_Reverse_Logo.png?width=3022&height=849&name=FN_Reverse_Logo.png "FN_Reverse_Logo")](https://fivenines.com/) [![FiveNinesPrimaryLogo](https://blog.fivenines.com/hs-fs/hubfs/FiveNinesPrimaryLogo.png?width=3022&height=849&name=FiveNinesPrimaryLogo.png "FiveNinesPrimaryLogo")](https://fivenines.com/) - [Solutions](https://fivenines.com/solutions/) - [Managed IT Services](https://fivenines.com/solutions/managed-it-services/) - [Cybersecurity Services](https://fivenines.com/solutions/cybersecurity/) - [Cloud & Productivity](https://fivenines.com/solutions/cloud-productivity/) - [Projects & Enhancements](https://fivenines.com/solutions/it-projects/) - [Placement Services](https://fivenines.com/solutions/onsite-it/) - Industries - [Finance & Banking](https://fivenines.com/industries/banking/) - [Healthcare](https://fivenines.com/industries/healthcare/) - [Legal](https://fivenines.com/industries/legal/) - [Nonprofit](https://fivenines.com/industries/non-profit/) - [Manufacturing & Logistics](https://fivenines.com/industries/manufacturing-logistics/) - [Small & Mid-Sized Businesses](https://fivenines.com/industries/smb/) - [Insights](https://fivenines.com/resources/) - [Resource Library](https://fivenines.com/resources/) - [Blog](https://blog.fivenines.com) - [About](https://fivenines.com/about/) - [About Five Nines](https://fivenines.com/about/) - [Leadership Team](https://fivenines.com/our-team/) - [Community Impact](https://fivenines.com/community/) - [Partnerships](https://fivenines.com/partnerships/) - [Careers](https://fivenines.com/careers/) - [Company News](https://fivenines.com/news/) Let's Talk Get Support Toggle Menu Toggle Menu Let's Talk Get Support - [Solutions](https://fivenines.com/solutions/) - [Managed IT Services](https://fivenines.com/solutions/managed-it-services/) - [Cybersecurity Services](https://fivenines.com/solutions/cybersecurity/) - [Cloud & Productivity](https://fivenines.com/solutions/cloud-productivity/) - [Projects & Enhancements](https://fivenines.com/solutions/it-projects/) - [Placement Services](https://fivenines.com/solutions/onsite-it/) - Industries - [Finance & Banking](https://fivenines.com/industries/banking/) - [Healthcare](https://fivenines.com/industries/healthcare/) - [Legal](https://fivenines.com/industries/legal/) - [Nonprofit](https://fivenines.com/industries/non-profit/) - [Manufacturing & Logistics](https://fivenines.com/industries/manufacturing-logistics/) - [Small & Mid-Sized Businesses](https://fivenines.com/industries/smb/) - [Insights](https://fivenines.com/resources/) - [Resource Library](https://fivenines.com/resources/) - [Blog](https://blog.fivenines.com) - [About](https://fivenines.com/about/) - [About Five Nines](https://fivenines.com/about/) - [Leadership Team](https://fivenines.com/our-team/) - [Community Impact](https://fivenines.com/community/) - [Partnerships](https://fivenines.com/partnerships/) - [Careers](https://fivenines.com/careers/) - [Company News](https://fivenines.com/news/) # Why is my Domain Being Flagged as Spam? [Five Nines Technicians](https://blog.fivenines.com/author/five-nines-it) : Dec 15, 2023, 12:23:53 PM 2 min read [IT Tips & Tricks](https://blog.fivenines.com/topic/it-tips-tricks) ![Why is my Domain Being Flagged as Spam?](https://blog.fivenines.com/hubfs/Blog%20Feature%20Images/122023_DomainFlaggedAsSpam.png) *TL;DR* - Your domain’s sending reputation is fragile: even a tiny number of spam complaints, bounces, or spam‐trap hits can tank deliverability. - Good engagement, clean lists, correct authentication (SPF/DKIM/DMARC), and compliant, mobile‑friendly content help keep your emails landing in the inbox. - Treat bulk email as a trust channel: use (double) opt‑in, honor opt‑outs quickly, and follow CAN‑SPAM and best practices to protect your reputation over time. Have you had an issue with email deliverability or your domain being flagged as spam? The industry standard for spam complaints is 0.1%. This means if you send an email campaign to 10,000 recipients, just 10 of those people can report it as spam before your [domain reputation](https://www.mailmodo.com/guides/domain-reputation/) will be impacted. For most small and mid-sized businesses that are sending to even fewer recipients, just one reported message can quickly diminish your sending reputation.   There are a number of considerations to factor in when addressing your domain reputation and improving your email deliverability for your business. In this article, you'll find the top factors that affect deliverability and how to maintain a good sending reputation for your domain.   ## **What Affects Email Deliverability**: - **Engagement** How often emails from your domain are opened and replied to, instead of simply deleted or marked as spam. - **Volume** The volume and frequency of emails you are sending out. - **Unsubscribes** The rate at which your recipients have unsubscribed from your emails. - **Spam Complaints** The number of recipients that reported your emails as spam. - **Spam Traps** Major Internet Service Providers (ISPs) set up accounts that look like normal email accounts, but are designed to target and eliminate email spam. If you send emails to to a [spam trap accoun](https://help.campaignmonitor.com/spam-trap-email-addresses)t by mistake then you will get added to a block list. - **Soft and Hard Bounces** Soft bounces are usually temporary email delivery problems, but hard bounces happen when you've entered the wrong email address, the recipient's mailbox is full, or you have incorrect SPF and/or DKIM configured. If you're seeing a large quantity of hard bounces, this may be due to improper public DNS settings. - **Domain Authentication** When mail systems receive a new message, they evaluate the message to determine if it's a spam or phishing email before passing legitimate emails on to the intended recipient. One of the first things mail systems do is look for three published DNS records (SPF, DKIM, & [DMARC](https://blog.fivenines.com/bulk-email-for-businesses)) which contain information about what email systems may send mail using your company's email domain. It's imperative that these three records are configured correctly and reviewed regularly for your emails to make it to their intended recipients. - **Content** Spam filters look at the email message itself for a variety of [spam indicators](https://eepurl.com/dyikjD), scanning your email's calls to action, subject lines, the number and type of attachments, and the message body. These filters are looking for indicators such as a sense of urgency, money-related (FREE! / Buy Now!) subject lines, odd punctuation or capitalization, pictures with embedded links, shortened URLs, adult-oriented language (expletives and/or language that is sexual in nature), links to known malicious websites, and more. - **Mobile-friendly content** Marketing emails have to be mobile friendly, or users will simply report it as spam to get it out of their feed. - **IP reputation** The behavior quality of the IP address you are sending from has an impact on deliverability. An example is that Office 365 has refined bulk email controls to prevent one Office 365 customer from ruining the IP reputation of all Office 365 IPs, since they are shared among many customers. If your sending domain is tied to directly to your own IP, only your email behavior should affect your domain's IP reputation. - **Domain reputation** The behavior quality associated with the email domain sending communications acts as your overall scorekeeper. The more marks you receive in any of the above categories, the more your overall domain reputation will be affected.   ## Sending Bulk Emails Responsibly If you are sending external emails to recipients by the thousands, [bulk email best practices](https://blog.fivenines.com/bulk-email-for-businesses) should be top of mind for email deliverability and reputation. Your company's bulk email lists should be opt-in at a minimum, preferably double opt-in when possible for the best domain reputation protection. Double opt-in means they signed up for the mailing list, and then you sent them a confirmation email and they approved it upon receipt, whereas only an initial signup action constitutes a single opt-in. Following opt-in best practices, honoring opt-out requests, and [adhering to CAN-SPAM laws](https://blog.fivenines.com/bulk-email-for-businesses#bulk-email) are all necessities for sending bulk emails as a business of any size in any industry.   [![CONTACT FIVE NINES](https://no-cache.hubspot.com/cta/default/1857420/406a9f41-1834-4f19-b8e8-06be70b2d7a9.png)](https://cta-redirect.hubspot.com/cta/redirect/1857420/406a9f41-1834-4f19-b8e8-06be70b2d7a9) ## Frequently asked questions Why does such a small number of spam complaints matter so much? The industry benchmark for spam complaints is about 0.1%, which means as few as 10 complaints on 10,000 messages can start to hurt your reputation. When you send to smaller lists, even a single “this is spam” click can signal to providers that your mail is unwanted, leading to more aggressive filtering or blocking. What are the biggest technical factors that affect deliverability? Key technical drivers include your bounce rate (especially hard bounces), whether you are hitting spam traps, and whether your domain is correctly authenticated with SPF, DKIM, and DMARC. When those records are missing or misconfigured, receiving servers are more likely to treat your messages as suspicious or reject them outright. How do engagement and content influence whether we land in the inbox? Mailbox providers watch how people interact with your messages. Emails that are opened, read, and replied to (rather than deleted or ignored) boost your reputation. On the flip side, content that looks spammy — misleading subject lines, excessive urgency, “FREE!!!” style language, sketchy links, or non‑mobile‑friendly layouts — raises red flags with filters and recipients alike. What can we do to improve our domain reputation if it is already damaged? Start by fixing the basics: clean your lists to remove invalid addresses and chronic non‑engagers, correct your SPF/DKIM/DMARC records, and slow down bulk sends while you rebuild trust. Focus on sending highly relevant, permission‑based messages to people who genuinely want them, and monitor spam complaints, bounce rates, and engagement over time. What are the essentials for sending bulk email responsibly? Use opt‑in (ideally double opt‑in) for your lists, give every recipient a clear way to unsubscribe, honor opt‑out requests promptly, and ensure your headers, from address, and subject lines are accurate and non‑deceptive. Combine that with sound technical setup and list hygiene, and you greatly increase the odds that your campaigns reach the inbox instead of the spam folder. ## Related Blog Posts [![Bulk Emailing for Small & Mid-Sized Businesses | What You Need to Know](https://blog.fivenines.com/hubfs/Blog%20Feature%20Images/122023_BulkEmailing.png)](https://blog.fivenines.com/bulk-email-for-businesses) #### [Bulk Emailing for Small & Mid-Sized Businesses | What You Need to Know](https://blog.fivenines.com/bulk-email-for-businesses) In a recent development, both Yahoo and Google have chosen to make DMARC a requirement for email delivery. This move is a significant step toward... [Cybersecurity](https://blog.fivenines.com/topic/cybersecurity) [Tech Trends](https://blog.fivenines.com/topic/tech-trends) [Compliance](https://blog.fivenines.com/topic/compliance) [IT Tips & Tricks](https://blog.fivenines.com/topic/it-tips-tricks) [Read More](https://blog.fivenines.com/bulk-email-for-businesses) [![Spam Filtering: Why It's Important And How It Works](https://blog.fivenines.com/hubfs/Blog%20Feature%20Images/110123_Spamfiltering.png)](https://blog.fivenines.com/spam-filtering-why-its-important-and-how-it-works) #### [Spam Filtering: Why It's Important And How It Works](https://blog.fivenines.com/spam-filtering-why-its-important-and-how-it-works) Once spam hits your email inbox, you become a target. When it comes to technology, humans tend to be the weakest link in most IT security situations.... [Phishing](https://blog.fivenines.com/topic/phishing) [Cybersecurity](https://blog.fivenines.com/topic/cybersecurity) [Read More](https://blog.fivenines.com/spam-filtering-why-its-important-and-how-it-works) [![What is Smishing? How to Identify + Report It](https://blog.fivenines.com/hubfs/Blog%20Feature%20Images/DTG-Migration_Smishing.jpg)](https://blog.fivenines.com/what-is-smishing) #### [What is Smishing? How to Identify + Report It](https://blog.fivenines.com/what-is-smishing) SMS phishing (“smishing”) is a form of phishing in which an attacker uses SMS text messages to trick recipients into taking an action and... [Phishing](https://blog.fivenines.com/topic/phishing) [Cybersecurity](https://blog.fivenines.com/topic/cybersecurity) [Tech Trends](https://blog.fivenines.com/topic/tech-trends) [IT Tips & Tricks](https://blog.fivenines.com/topic/it-tips-tricks) [Read More](https://blog.fivenines.com/what-is-smishing) ## Let's get in touch   [**(402) 817-2630**](tel:402-817-2630) [help@fivenines.com](mailto:help@fivenines.com) [Lincoln, NE](https://fivenines.com/contact/lincoln) [Omaha, NE](https://fivenines.com/contact/omaha) [Kearney, NE](https://fivenines.com/contact/kearney) [Central City, NE](https://fivenines.com/contact/central-city) [St. Louis, MO](https://fivenines.com/st-louis) ![cyberverify-1](https://blog.fivenines.com/hs-fs/hubfs/cyberverify-1.png?width=110&height=110&name=cyberverify-1.png)![aicpa](https://blog.fivenines.com/hs-fs/hubfs/aicpa.png?width=110&height=110&name=aicpa.png) ### Are we a good fit? [![Schedule Consultation](https://no-cache.hubspot.com/cta/default/1857420/interactive-196258273705.png)](https://blog.fivenines.com/hs/cta/wi/redirect?encryptedPayload=AVxigLLRFttE9%2FEozM3hVJ89IxWWU2Ad9vGF3nTg1z6w5dUCovmgoHtwT0qieKN7zRnC1Y7ktRe%2Fl5P9XRvCWMfL7cj0%2FLt8Jk5WmFMTc03PyFE3lZpGEyWkwnx5Lwp9xQIXsOl7RFW7z4W0yDA7Xnd%2BdQcQdliqCvJSyI3jyjPaFmG2gxOtyaCIYIeMcgD1Ce7y8hvzcQ%3D%3D&webInteractiveContentId=196258273705&portalId=1857420)   - [Privacy Policy](https://fivenines.com/privacy-policy/) - [HTML Sitemap](https://fivenines.com/html-sitemap/) © 2026 Five Nines Technology Group | 5617 Thompson Creek Blvd Lincoln, NE 68516 [Facebook](https://www.facebook.com/gonines)[Linkedin](https://www.linkedin.com/company/five-nines-technology-group/) [Blog](https://blog.gonines.com/?__hstc=143714730.45718742b0726c421d8592d7ea71f58b.1757514685996.1758029308186.1758134756251.4&__hssc=143714730.31.1758134756251&__hsfp=1745665186)   [Client Support](https://fivenines.com/client-login/) Return to top ```json { "@context" : "https://schema.org", "@type" : "FAQPage", "mainEntity" : [ { "@type" : "Question", "acceptedAnswer" : { "@type" : "Answer", "text" : "The industry benchmark for spam complaints is about 0.1%, which means as few as 10 complaints on 10,000 messages can start to hurt your reputation. When you send to smaller lists, even a single “this is spam” click can signal to providers that your mail is unwanted, leading to more aggressive filtering or blocking." }, "name" : "Why does such a small number of spam complaints matter so much?" }, { "@type" : "Question", "acceptedAnswer" : { "@type" : "Answer", "text" : "Key technical drivers include your bounce rate (especially hard bounces), whether you are hitting spam traps, and whether your domain is correctly authenticated with SPF, DKIM, and DMARC. When those records are missing or misconfigured, receiving servers are more likely to treat your messages as suspicious or reject them outright." }, "name" : "What are the biggest technical factors that affect deliverability?" }, { "@type" : "Question", "acceptedAnswer" : { "@type" : "Answer", "text" : "Mailbox providers watch how people interact with your messages. Emails that are opened, read, and replied to (rather than deleted or ignored) boost your reputation. On the flip side, content that looks spammy — misleading subject lines, excessive urgency, “FREE!!!” style language, sketchy links, or non‑mobile‑friendly layouts — raises red flags with filters and recipients alike." }, "name" : "How do engagement and content influence whether we land in the inbox?" }, { "@type" : "Question", "acceptedAnswer" : { "@type" : "Answer", "text" : "Start by fixing the basics: clean your lists to remove invalid addresses and chronic non‑engagers, correct your SPF/DKIM/DMARC records, and slow down bulk sends while you rebuild trust. Focus on sending highly relevant, permission‑based messages to people who genuinely want them, and monitor spam complaints, bounce rates, and engagement over time." }, "name" : "What can we do to improve our domain reputation if it is already damaged?" }, { "@type" : "Question", "acceptedAnswer" : { "@type" : "Answer", "text" : "Use opt‑in (ideally double opt‑in) for your lists, give every recipient a clear way to unsubscribe, honor opt‑out requests promptly, and ensure your headers, from address, and subject lines are accurate and non‑deceptive. Combine that with sound technical setup and list hygiene, and you greatly increase the odds that your campaigns reach the inbox instead of the spam folder." }, "name" : "What are the essentials for sending bulk email responsibly?" } ] } ```