Summary
The prevalence of spam emails continues to be a significant challenge in the digital landscape. While the term spam often brings to mind obvious scams, a growing concern revolves around unsolicited messages that appear highly legitimate. These can originate from a variety of platforms, including popular email service providers (ESPs) and cloud infrastructure providers, which inadvertently or sometimes knowingly facilitate such traffic. Understanding which platforms are most commonly leveraged for sending spam emails, whether intentional or not, is crucial for both recipients and those working in email deliverability.
Key findings
- Email is primary: Email remains the most common channel for receiving spam, with a significant portion of users reporting it as their primary source of unsolicited messages (EmailTooltester.com).
- Marketing spam dominates: Marketing and advertising emails constitute the largest percentage of all spam, making up approximately 36% of unsolicited email traffic.
- Cloud provider challenges: Major cloud providers, including Amazon SES, Gmail, and Microsoft (Outlook), are frequently identified as significant sources of spam, particularly in B2B contexts.
- Phishing through email: A vast majority (an estimated 91%) of cyberattacks, especially phishing, originate via email.
- Botnet reliance: A large volume of spam is sent through botnets, which are networks of compromised devices.
Key considerations
- Improving detection: Corporate phishing filters are becoming more sophisticated, capable of identifying even very legitimate-looking spam or phishing attempts.
- B2B spam disguises: Much of the B2B spam from large platforms is cleverly disguised as personalized or carefully chosen outreach, making it harder to distinguish.
- ESPs and compliance: Email service providers face ongoing challenges in effectively policing sending, particularly in B2B environments where traditional compliance methods may fall short. You can learn more about why ESPs send unsolicited marketing emails.
- Filter evolution: Email filters are expected to become even stricter and more selective, with a decreasing tolerance for false positives, impacting legitimate marketing efforts.
- Understanding spam triggers: To avoid landing in spam folders, it's essential to understand why emails go to spam and to proactively improve deliverability, even when using common platforms.
What email marketers say
Email marketers often find themselves navigating the fine line between legitimate outreach and unwanted messages. Their experiences shed light on the pervasive nature of spam and the challenges associated with maintaining good sender reputation when common platforms are also used for abusive sending. They frequently encounter the frustration of well-intentioned emails being flagged as spam due to the overall reputation of shared sending infrastructures, or the sheer volume of spam originating from certain mainstream providers.
Key opinions
- Phishing detection improvement: Even highly legitimate-looking phishing emails are now frequently landing in spam folders, suggesting corporate phishing filters are becoming highly effective.
- Frustration over FBL data: The lack of Feedback Loop (FBL) data makes it challenging for marketers to understand and improve their email deliverability performance, especially when their emails are being mistakenly classified as spam.
- Cloud provider complexities: Marketers perceive that all major cloud providers struggle with effective spam policing, especially in complex B2B environments, leading to messy sending landscapes.
- Misleading B2B outreach: There's a concern that much of what's labeled as customized and carefully chosen outreach mail from large platforms is, in fact, simply spam.
- Shifting landscape: The sentiment is that while ESPs might become less restrictive, mail clients and filters will continue to become less friendly to marketing efforts.
Key considerations
- Adapting to stricter filters: As filters become more selective and less tolerant of false positives, marketers must refine their sending practices. Learn about how email blacklists actually work to better navigate these changes.
- Impact of shared IPs: Marketers using shared IP addresses on platforms where spam originates need to be acutely aware of how this can affect their deliverability.
- Monitoring deliverability: Continuous monitoring of inbox placement and deliverability is essential, especially when dealing with platforms that are common sources of spam. Regularly checking your sender reputation is vital.
- Recognizing disguised spam: Marketers should be able to identify sophisticated spam, even if it appears to be legitimate outreach, to better protect their own lists and practices.
Marketer view
Marketer from Email Geeks seeks examples of highly legitimate-looking phishing emails and their headers to demonstrate their deceptive nature to others. They are looking for realistic examples to educate people.
Marketer view
Marketer from Email Geeks requests the full body of phishing emails to illustrate how convincing they can appear to recipients, as their current examples are clearly fake.
What the experts say
Experts in email deliverability and anti-spam generally agree that the issue of spam originating from popular platforms is multifaceted. They delve into the incentives (or lack thereof) for ESPs to rigorously police their sending customers, the evolution of filtering technologies, and the broader trends impacting the email ecosystem. Their insights are crucial for understanding the underlying dynamics that allow spam to persist and adapt.
Key opinions
- Amazon SES usage: There's an observed increase in spammer use of Amazon SES, possibly due to more networks blocking or throttling AWS IPs, despite it still being less than spam from Gmail and Outlook.
- Gmail and Microsoft as sources: Gmail and Microsoft (Outlook) are cited as major sources of B2B spam, often disguised as legitimate outreach messages.
- Compliance challenges: ESP compliance efforts are expected to decline before improving, necessitating significant innovation and investment to enhance spam prevention effectively.
- Diminished ESP incentive: Modern filtering methods (such as granular blocking) reduce the incentive for ESPs to aggressively remove bad customers, as isolated bad sending streams now primarily harm only the spammers themselves.
- Stricter filters and false positives: Filters are becoming more selective and less concerned with false positives, indicating a tougher environment for all senders, including legitimate ones.
Key considerations
- Monitoring major ESPs: Organizations should be particularly vigilant when receiving emails from large platforms like Gmail, Outlook, and Amazon SES, as these are frequently exploited for spam.
- Investment in anti-spam: ESPs need to invest more in innovative solutions beyond traditional methods (like GPT and FBLs) that are ineffective in B2B environments to combat spam effectively.
- Understanding filter evolution: Senders must anticipate that mail clients and filters will continue to become less marketer-friendly, requiring a continuous adaptation of sending strategies.
- Domain reputation management: For any sender, managing domain reputation is critical, especially given that bad actors can disproportionately impact perception of broad sending platforms. This includes understanding how Microsoft classifies spam.
Expert view
Expert from Email Geeks observes increased spammer activity on Amazon SES, attributing it potentially to network blocking or throttling of AWS IPs, though noting it's still less than spam from Gmail and Outlook.
Expert view
Expert from Email Geeks asserts that ESP compliance is likely to worsen before improving, necessitating significant innovation and resource investment for more effective spam prevention strategies.
What the documentation says
Official documentation and research often provide a more formal, statistical, and technical perspective on spam origins and types. This includes insights into the mechanisms by which spam is distributed, the primary categories of spam content, and the pervasive nature of email as a medium for malicious activities like phishing. Understanding these foundational insights helps frame the broader problem of unwanted email.
Key findings
- Botnet as a primary vector: A significant portion of spam emails are sent via botnets, which are networks of compromised computers and internet-connected devices.
- Commercial intent: Spam is typically sent for commercial purposes, ranging from unsolicited advertisements to promotional offers for questionable products.
- Email's role in cyberattacks: Email is overwhelmingly the most popular method for conducting cyberattacks, particularly phishing, with a vast majority of attacks initiating through this channel.
- Common spam types: Common spam subjects include pharmaceuticals, adult content, financial services, and work-from-home schemes.
- Platform exploitation: Content management systems (CMS), email marketing platforms, and survey platforms can be exploited to host or send phishing attacks.
Key considerations
- Securing digital infrastructure: The widespread use of botnets necessitates robust cybersecurity measures to prevent devices from being compromised and used for spamming. This includes understanding email authentication protocols.
- Identifying phishing variants: Awareness of various phishing types, beyond general email phishing, is essential for comprehensive protection. One example is understanding suspicious email domains.
- Platform accountability: There's an ongoing discussion about the accountability of CMS, email marketing, and survey platforms in preventing their services from being misused for phishing attacks. The FTC provides guidance on how to get less spam.
Technical article
Documentation from Consumer Advice FTC explains that millions of internet-connected devices, including computers and smart cameras, form part of botnets. It states that most spam is sent through these botnets, highlighting the automated and widespread nature of spam distribution.
Technical article
Documentation from Cisco indicates that spam emails typically serve commercial purposes and are often dispatched in massive volumes via botnets. This underscores the scale and profit-driven nature of spam operations.
Related resources
13 resources
Related pages
Why do emails go to spam, and how does high sending frequency affect deliverability?
Why do emails from new domains go to spam with low sending volumes?
How to identify suspicious email domains and spamtrap networks?
Which email blocklists are most important to monitor for deliverability issues?
What happens when your domain is on an email blacklist?
A simple guide to DMARC, SPF, and DKIM
How email blacklists actually work: a simple guide
A practical guide to understanding your email domain reputation
Why Your Emails Fail: Expert Guide to Improve Email Deliverability [2025]
Email Deliverability Issues: Getting Your Messages to the Inbox in 2025
