What Is Spam Email? Definition, Types & How to Stop It

If you’ve ever wondered what is spam email and why your inbox seems to be overflowing with unwanted messages, you’re not alone. Spam emails are unsolicited messages sent in bulk, often for advertising or scams, that can clutter your inbox and create security risks.

Although completely eliminating spam isn’t easy, understanding what it is and how it works can help you take steps to reduce it and protect yourself from its adverse impacts.

What Is Spam Email?

Spam email, often referred to as junk email, encompasses unsolicited messages sent in bulk, typically for advertising, phishing, or spreading malware. In 2024, it was estimated that 361 billion spam emails were sent daily worldwide. The United States led this trend, sending approximately 8 billion spam emails per day. 

These unsolicited emails can clutter inboxes, waste time, and pose security risks. Understanding what spam email is and how it operates is the first step toward mitigating its effects.

How spam email works

Spammers use automated software, known as bots, that can generate and send thousands or even millions of emails in a short time. These programs harvest email addresses from public websites, social media, or previous data breaches, creating huge lists of targets.

Once the email addresses are collected, spammers send out their messages, which often contain advertisements, scams, or malicious links. Because these emails are unsolicited, many email providers use filters to identify and block them, but spammers continuously adapt by changing their tactics. For example, they might disguise links, use fake email addresses, or embed images instead of text to avoid detection. 

There is also “human spam”, where real people manually send spam emails, especially for more targeted attacks, such as phishing. In these cases, the spammer might tailor messages to trick the recipient into revealing sensitive information, such as passwords or financial details.

Common Types of Spam Emails

Spam emails come in various forms, each designed to serve a different purpose—whether it’s to promote products, steal information, or spread malware.

Promotional spam

Promotional spam is one of the most common types of spam emails. These messages are usually bulk advertisements sent without your consent, promoting products, services, or deals. While some promotional emails may be harmless, they often clutter your inbox with irrelevant offers, making it harder to spot important messages. Because they’re sent in massive volumes, they’re typically ignored or deleted without being read.

Phishing emails

Phishing emails are designed to trick you into revealing sensitive information, such as passwords, credit card numbers, or Social Security numbers. These emails often appear to come from trusted sources, such as your bank or a popular service, using urgent language or alarming messages to prompt quick action. Clicking on links or downloading attachments in phishing emails can lead to identity theft or financial loss.

Malware attachments

Some spam emails carry dangerous attachments containing malware or viruses. Opening these files can infect your device with malicious software that can steal data, damage files, or give attackers control over your system. Malware attachments are often disguised as invoices, receipts, or other seemingly legitimate documents to lure you into opening them.

Scams and hoaxes

Scam and hoax emails attempt to deceive you with false promises or alarming lies. Common examples include fake lottery winnings, inheritance claims, or urgent pleas for help from a “friend” in distress. 

These messages typically attempt to extract money or personal information by exploiting emotions such as greed, fear, or sympathy. If you’re unsure how to tell if an email is a scam, watch out for generic greetings, urgent messages, and suspicious links.

Spear phishing and business email compromise (BEC)

Unlike regular phishing, spear phishing targets specific individuals or organizations. Attackers research their victims to craft highly personalized messages that appear legitimate. Business Email Compromise (BEC) is a famous phishing attack where attackers impersonate executives or partners to trick employees into transferring money or sensitive data. Because these emails are tailored and convincing, they can be very difficult to detect.

Protect Against Spam Emails with PowerDMARC!

How Spam Email Affects You

Spam emails don’t just clutter your inbox. In fact, they can have wide-reaching effects on both your personal life and business operations. From lost time to serious security risks, understanding these impacts is key to managing and minimizing spam.

Productivity loss

One of the most obvious effects of spam is the constant clutter it creates. Sorting through piles of irrelevant messages wastes valuable time and disrupts your workflow. 

In busy workplaces, this can slow down productivity, lead to missed important emails, or even mislabeling legitimate ones, a common reason why emails go to spam folders unintentionally.

Security threats

Spam is also a major security risk. Many spam emails contain malware, ransomware, or phishing attempts designed to trick you into clicking malicious links or downloading harmful attachments. 

These attacks can result in stolen personal information, identity theft, or even system takeover. While modern spam filters catch most threats, some still manage to slip through, making vigilance essential.

Financial impact

The financial toll of spam and related scams is significant. Phishing, in particular, carries direct costs that can heavily impact your company. In 2023, the average global cost of a data breach reached $4.45 million.

For individuals, falling victim can mean having their bank details or credit card information stolen through fraud. For businesses, the costs go beyond theft. They include expenses related to incident remediation, downtime, and costly upgrades to IT security systems to defend against ongoing attacks.

Network and server strain

Spam can burden the IT infrastructure. Organizations experience increased bandwidth usage and storage demands as spam floods their servers, overwhelming their systems. 

This overload can reduce overall server performance, slowing down legitimate communications and forcing IT teams to invest time and resources into managing the extra load.

How to Stop Spam Emails

While completely eliminating spam emails isn’t possible, there are effective steps you can take to significantly reduce them. Start by improving your email security with authentication tools like DMARC, which verify the origin of messages and block phishing attempts. 

Be cautious about sharing your email address and avoid replying to spam emails, as this confirms your address is active and can lead to more spam. 

Use spam filters

Most email services, like Gmail and Outlook, come with built-in spam filters that help keep unwanted emails out of your inbox. In Gmail, you can customize your spam settings and mark suspicious emails as spam to train the filter to recognize similar messages in the future. 

Outlook offers similar tools to block senders and move junk emails automatically to the spam folder. Using these features regularly helps keep your inbox cleaner and safer.

Report spam

Replying to spam emails is generally a bad idea because it confirms to spammers that your email address is active, which often leads to more spam or even targeted attacks. Instead of replying, use your email provider’s “Report spam” or “Report phishing” button.

Reporting spam helps improve spam filters by alerting your email service about new threats. You can usually find this option near the “Delete” button in your email interface. 

Unsubscribe carefully

Unsubscribing from newsletters or marketing emails is a good way to reduce unwanted messages, but it’s important to do it cautiously. Only click “unsubscribe” links in emails from legitimate and trusted sources. 

Enable email authentication protocols

If you manage your own email domain, enabling email authentication protocols like SPF, DKIM, and DMARC is crucial. These tools help verify that emails sent from your domain are legitimate, making it much harder for spammers and phishers to spoof your address. Most email hosting services offer step-by-step guides for setting up these records. Properly configured authentication not only protects your domain but also improves email deliverability to your recipients.

If an email looks suspicious or comes from an unknown sender, clicking unsubscribe might actually confirm your address to spammers or even lead you to harmful websites. 

When in doubt, it’s safer to mark the email as spam or block the sender rather than unsubscribe. Always keep an eye out for signs like poor grammar, unusual sender addresses, or urgent language, which may indicate a trap.

Secure Your Email with PowerDMARC

Spam emails clutter inboxes and pose serious risks, from wasting time to enabling phishing, malware, and scams. These threats affect both individuals and businesses, causing productivity loss, financial damage, and IT strain. While spam can’t be fully stopped, using filters, careful reporting, and cautious unsubscribing helps reduce it.

One powerful way to strengthen your email defenses is with PowerDMARC. By implementing DMARC authentication, PowerDMARC helps verify legitimate emails and blocks phishing and spoofing attacks, protecting your domain and giving you better control over your email security.

Protect your inbox and business with PowerDMARC. Try it free or book a demo today!

Frequently Asked Questions

Is spam email illegal?

Yes, in many countries, sending unsolicited spam emails is illegal under laws like CAN-SPAM in the U.S. However, enforcement can be challenging, and not all spam is caught or penalized.

How do spammers get my email address?

Spammers collect email addresses through data breaches, harvesting from websites and social media, buying lists, or using automated bots to scrape publicly available info.

Are newsletters I didn’t sign up for considered spam?

Generally, yes. If you receive newsletters without your consent, they are considered spam, especially if they’re unsolicited and unwanted marketing messages.

• About
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Ahona Rudra

Domain & Email Security Expert at PowerDMARC

Ahona is the Marketing Manager at PowerDMARC, with 5+ years of experience in writing about cybersecurity topics, specializing in domain and email security. Ahona holds a post-graduation degree in Journalism and Communications, solidifying her career in the security sector since 2019.

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