14 Best Email Spam Blockers and Filters Compared

Find the Best Anti-Spam Solution for Your Needs

In 2025, about 45% of all email was spam, according to Kaspersky. Clean Email’s 2026 spam research puts that at roughly 169–176 billion spam messages a day and projects about 256 billion a day by 2030 in its moderate scenario (208–350 billion, depending on how well filters keep up). Let’s start with the type of anti-spam solution you’re looking for—click on the situation that fits you best:

• I’m looking for an email anti-spam appliance for my iPhone/Android device.
• I want an email spam blocker for my Gmail, Outlook, Apple Mail, Yahoo, iPhone—you name it.
• I’m looking for a cloud-based anti-spam protector.
• I’m looking for server-hosted anti-spam software.
• I’m interested in enterprise anti-spam solutions.

Which Type of Spam Filter Do You Need?

However, if you don’t know exactly what you’re looking for, or the difference between cloud, server, and client-based tools isn't clear yet, the choice really comes down to two things: where your email lives and who you're protecting.

A single spam operation can run 50 to 500 or more sending domains, rotating to a fresh one the moment one is blocked, so an automated filter beats blocking senders by hand.

Here's how the main types compare:

On mobile, spam protection usually comes with the cloud-based tools, since they filter from any device. Client add-ons are tied to a desktop.

Best for Regular Gmail, Outlook, and Other Email Services

These are spam filtering solutions suitable for personal or small business users with standard email accounts like Gmail, Outlook, or Yahoo Mail.

• Clean Email – Holds mail from new senders until you approve them with Screener, and lets you block a sender or a whole domain with its email spam blocker. Try it free (Screener is included in the free trial and paid plans).
• Spam Bully – Integrates well with Outlook and other email clients.
• SpamSieve – Great for Apple Mail users.
• SPAMfighter – Useful for non-English users and personal email protection.
• MailWasher – An easy-to-use anti-spam tool for individuals.

Cloud-Based Email Spam Blockers

I'm sure this is a great choice for personal use. Why? Because these email anti-spam solutions work in the cloud, so there's no need for on-site hardware. It's much easier to access and use.

• N-Able Mail Assure – A cloud-based spam filtering solution with advanced threat protection.
• SpamTitan – Offers both cloud and gateway-based solutions, making it highly flexible.
• Proofpoint Total Protection (formerly Hornetsecurity) – A cloud-based filter specifically designed for Office 365 users.
• Symantec Email Security.cloud – A cloud-native enterprise solution for anti-spam and email security.
• MailChannels – A cloud-based filtering and email delivery solution.
• MX Guarddog – Operates entirely in the cloud with affordable pricing per email address.

Server-Hosted Anti-Spam Solutions

I like these spam-blocking solutions because they're super powerful. However, they're best suited for organizations with a dedicated IT infrastructure since they need to be installed on local mail servers or dedicated gateways.

• Securence – Designed for spam protection for businesses and nonprofits, requiring server-side setup.
• Comodo Secure Email Gateway – A dedicated on-premises or hybrid security email anti-spam gateway for businesses.
• Apache SpamAssassin – A free, open-source filter you install on your own mail server.

Best Email Anti-Spam Appliances for Mobile Usage

Many email security solutions work well on desktops and mail servers, but not all are optimized for mobile usage. That’s why I’ve listed mobile-friendly options separately.

Some offer dedicated mobile apps, while others provide cloud-based filtering that works seamlessly on any device.

Mobile apps for hands-on email spam management

• Clean Email – Full-featured iOS and Android apps, allowing users to filter spam, unsubscribe from emails, and manage their inboxes from mobile.
• SpamSieve – Compatible with Apple Mail on iOS, but requires a Mac to function properly.

Fully mobile-compatible cloud-based spam blockers

These anti-spam tools protect your inbox regardless of whether you check your email on a smartphone, tablet, or desktop.

• N-Able Mail Assure – Accessible via mobile browsers but no dedicated mobile app.
• SpamTitan – Web-based interface that works on mobile.
• Proofpoint Total Protection (formerly Hornetsecurity) – Fully cloud-based and optimized for Office 365 users, accessible via mobile.
• MailChannels – Cloud-based and works seamlessly for mobile email filtering.
• Symantec Email Security.cloud – Cloud-native solution that filters spam at the server level, protecting mobile inboxes without requiring installation.
• MX Guarddog – Affordable spam filtering that works across mobile devices via standard email integration.

Enterprise Spam Filtering Services

These solutions provide advanced spam filtering and security features designed for businesses.

• N-Able Mail Assure – Ideal for enterprises requiring high accuracy.
• SpamTitan – Widely used in enterprises and MSPs.
• Securence – Built for businesses and nonprofits.
• Comodo Secure Email Gateway – Designed for large enterprises with high email volume.
• Proofpoint Total Protection (formerly Hornetsecurity) – Focuses on securing Office 365 environments.
• MailChannels – Improves email deliverability for enterprises.
• Symantec Email Security.cloud – Provides enterprise-level security and compliance features.

14 Best Anti-Spam Software Tools and Email Spam Filters

1. Clean Email’s Screener

Price: Included in all Clean Email plans (available for 1, 5, or 10 inboxes) and in the free trial

• Cloud-based
• Paid
• Best for Gmail, Outlook, Yahoo, iCloud, AOL, Zoho, GMX, and any other mail provider

Clean Email’s Screener tool is a cloud-based spam-blocking feature that keeps your inbox free from unwanted and unknown senders.

💡 Unlike standard spam filters, which only catch obvious junk, Screener holds all emails from new senders (anyone who hasn’t emailed you before) until you approve them. This means no more unexpected marketing emails, phishing attempts, or clutter in your inbox.

How Clean Email’s Screener works

Any email from a sender who hasn’t emailed you before is held for your review, so your Inbox stays in control. It works instantly once enabled, with a simple approval process that takes just one click.

You can also manage Screener from your AI assistant. Connect Clean Email to Claude, ChatGPT, or Codex, then ask in your own words: approve or block senders waiting in Screener, block a whole domain, or set up a rule for repeat junk. Your assistant explains what each action will do, and Clean Email acts only on what you approve. Here’s how to connect Clean Email to your AI assistant.

Why choose Screener by Clean Email?

• Cloud-based & fully compatible with all devices and email providers (Gmail, Outlook, Yahoo, iCloud, and more).
• Fast, automatic setup that works in seconds.
• Holds spam and phishing from new senders for review, so they don’t land in your inbox.
• One-click approval for trusted senders, so you only manage new senders once.

Try Clean Email for free or use Clean Email spam blocker app for iPhone when on the move.

2. N-Able Mail Assure (formerly SolarWinds)

Price: Price on request (free trial available)

• Cloud-based
• Paid
• Enterprise-grade solution

N-Able Mail Assure is a cloud-based email spam-blocking service that offers a unique value proposition for many MSPs and IT Pros working in SMBs. The product has flexible pricing options and offers a 99.93% spam detection rate with zero false positives in Virus Bulletin’s VBSpam test, business continuity, and email archiving. N-Able Mail Assure was originally part of SolarWinds before N-Able became a separate company.

How N-Able Mail Assure works

N-able Mail Assure stands apart from its competitors because it is built on technology that is developed in-house. Whereas some other email security providers resell technology, N-able has full control over its tech stack and quickly responds to new email-borne threats.

Since Mail Assure is also a cloud-based email filtering service, it’s easy for individuals and businesses to configure and deploy, regardless of the systems they use. It also uses SSL/TLS traffic encryption, and seamless integration with Microsoft Office 365 and Outlook via an add-in and single sign-on.

Why choose N-Able Mail Assure?

• 99.93% spam detection in VBSpam testing, built on in-house technology rather than resold tech.
• Email archiving and business continuity keep mail available during outages.
• Integrates with Microsoft 365 and Outlook via an add-in and single sign-on.
• Quick to deploy for individuals and businesses on almost any system.

3. SpamBully

Price: $29.95 annually

• Paid
• Best for Outlook and other personal email clients

SpamBully is a relatively affordable email spam service at just $29.95 for a yearly subscription. It’s straightforward to install and intuitive to use, making it an accessible option for nearly any user. It offers detailed email information, phishing detection, spam blocking, message quarantine, and blocklist data.

How SpamBully works

While SpamBully offers a wide array of beneficial perks, one of its key features is its ability to learn what each user considers spam and adapt its settings based on your needs. The program will monitor your behavior over the first few weeks of use to determine how to filter spam in the future.

Unfortunately, one potential drawback of SpamBully is the fact that it is only available for Windows email clients, meaning Outlook (including Office 365 and Office 2021), Live Mail, Outlook Express, and Windows Mail.

However, for anyone using Outlook or Microsoft, this third-party email filter offers a robust suite of features that make it easy to keep your inbox clean and reduce the time you spend managing emails you aren’t interested in.

Why choose SpamBully?

• Learns what you treat as spam and adapts over your first few weeks of use.
• Recognizes sophisticated junk that simpler filters miss.
• Bundles phishing detection, quarantine, and blocklist data in one tool.
• A strong fit if you are on Windows and mainly use Outlook.

4. SpamSieve

Price: one-time purchase of $39.99 (single-user license)

• Paid (one-time license)
• Best for Apple users (Apple Mail, Outlook for Mac)

SpamSieve offers one of the most powerful and well-known spam filtering services for Mac, and the current version runs on macOS 10.13 High Sierra through macOS 27. There is no standalone iOS app, but SpamSieve running on your Mac can keep spam off your iPhone or iPad when you use an IMAP or Exchange account, and you can even train it remotely.

How SpamSieve works

Like SpamBully, SpamSieve uses adaptive learning capabilities to change its behavior over time. Additionally, this spam email blocker integrates with your macOS Contacts App to ensure that messages from your trusted contacts are never accidentally marked as spam. Furthermore, you can customize your SpamSieve experience through settings and scripts.

Unlike some other anti-spam software on this list, SpamSieve works as a plug-in to your current inbox. You manage everything from inside your email client. Although it’s only compatible with macOS, SpamSieve connects to Apple Mail, Outlook for Mac, Airmail, and other popular macOS email clients.

Why choose SpamSieve?

• One of the most accurate spam filters for macOS, with adaptive learning that improves over time.
• Runs as a plug-in inside your existing client, so there's no separate app to open.
• Works with Apple Mail, Outlook for Mac, Airmail, and other macOS clients.
• Reads your macOS Contacts so trusted senders are never flagged by mistake.

5. Securence

Price: Price on request

• Server-based, hosted email spam filter
• Paid
• Best for small businesses and nonprofits
• Enterprise-grade solution

Securence is a popular spam filtering service for small businesses, educational and governmental bodies, and enterprises. Interested parties can set up a 30-day free trial on their website, at which time they will receive a custom quote based on the size of their business and the scope of their needs.

How Securence works

One of the biggest benefits of Securence for businesses is the fact that it requires very little maintenance or upkeep once you work through the initial setup with your company email platform.

Another impressive feature is that it doesn’t just block spam email; it also notifies users when messages are blocked or quarantined. The software also filters and reads mail logs, effectively flags junk and malware, and even stops phishing attempts.

However, one of the features of Securence that I found most beneficial for modern companies is its business continuity service, which ensures that your organization will maintain access to email even in the event of an unexpected loss of service. Avoiding downtime is more crucial than ever in such a connected time, and Securence makes that a top priority.

Why choose Securence?

• Very low maintenance once the initial setup is done.
• Notifies you when messages are blocked or quarantined, with full mail-log filtering.
• Meets GLB and HIPAA standards, useful for regulated organizations.
• Business continuity service keeps email accessible during an outage.
• Built for small businesses, schools, and government bodies.

6. SpamTitan

Price: Price on request

• Cloud-based & Server-hosted options
• Paid
• Enterprise-grade solution

SpamTitan pledges to stop 99.9% of spam before it reaches your inbox, drastically reducing the time spent on managing your email accounts. Like Securence, SpamTitan provides a 30-day free trial to potential clients, including free technical support, after which interested users can seamlessly access their existing settings and information in the premium version.

How SpamTitan works

Unlike other options on this list, SpamTitan includes two different antivirus protection mechanisms to ensure that nothing, even potentially compromising, ever reaches your inbox. It scans all parts of inbound messages, including links and attachments.

Additionally, SpamTitan will scan and discover phishing email attacks, spear-phishing attacks, and zero-day attacks that may target your inbox.

SpamTitan combines machine learning and Bayesian analysis, which helps it work most effectively for you while also catching any new threats before you notice them. However, SpamTitan can be difficult to navigate, especially for less tech-savvy customers.

Why choose SpamTitan?

• Stops a claimed 99.9% of spam, with two antivirus engines scanning links and attachments.
• Detects phishing, spear-phishing, and zero-day attacks.
• Combines machine learning and Bayesian analysis to catch new threats.
• Available as cloud or server-hosted, with whitelisting support.

7. MailWasher

Price: Free (for single email address)

• Free version available
• Paid for premium features
• Best for personal Gmail, Outlook, and other email accounts

MailWasher claims a user base of over 8 million people, and it’s easy to see why so many have been drawn to its features and accessibility. In contrast to many other applications described above, MailWasher is the only spam email filter that offers an entirely free spam blocker in addition to a paid version.

How MailWasher works

Based on my testing, MailWasher offers the best free email spam filter for a single inbox. Regardless of which version of MailWasher you use, it will block spam before it reaches your inbox by previewing and deleting messages that seem suspicious.

Additionally, the program scans for offensive content and filters out messages it deems “inappropriate.”

While many users are content with the features available as part of the free version of MailWasher, there are substantial benefits to upgrading, from $49.95 (as an annual subscription, or a lifetime license for extra). In addition to all free features, premium users can use MailWasher with multiple addresses and receive technical support and other capabilities.

Why choose MailWasher?

• The strongest free option for filtering a single inbox.
• Previews and deletes suspicious mail before it reaches you.
• Filters out offensive or inappropriate content automatically.
• Works with all popular email services.

8. Comodo Secure Email Gateway

Price: Price on request

• Server-based, hosted email spam filter
• Paid
• Enterprise-grade solution
• Handles large message volumes

Designed for enterprise users, Comodo Secure Email Gateway is an email spam filtering service that can handle large volumes of unwanted email messages. It relies on Comodo’s patented containment technology, which allows users to open attachments in isolated containers, where they are analyzed to determine whether or not they’re safe. Only when an attachment is considered to be safe is it allowed to leave the container.

Comodo’s business security line has used the Xcitium brand since 2022, but this gateway is still sold on comodo.com.

How Comodo Secure Email Gateway works

Comodo Secure Email Gateway is a third-party spam filter available in the cloud, dedicated hosted cloud, and on-premises. All versions of this spam filtering solution offer many extra features, including full malware filtering, email classification, banner and plugin filtering, DoS attack prevention, and IPv6 support.

Furthermore, the program’s advanced filtering methods can help you easily trash or sort emails based on sender, attachment size, or keywords within the email.

While Comodo offers a powerful email spam blocker, its software is best suited for enterprise-level users.

Why choose Comodo Secure Email Gateway?

• Sandboxes every attachment in an isolated container before delivery.
• Handles large message volumes, suited to enterprise mail flows.
• Adds malware filtering, email classification, DoS protection, and IPv6 support.
• Available in the cloud, hosted cloud, or on-premises.
• Integrates with Comodo AV and Valkyrie.

9. SPAMfighter

Price: Free, or $29 for SPAMfighter Pro

• Free version available (with ads)
• Paid version for additional features
• Best for non-English users
• Best for personal email users

SPAMfighter is a Windows-only spam filter that plugs into Outlook, Outlook Express, Windows Mail, Windows Live Mail, and Thunderbird. Its listed requirements stop at Windows 10 and Outlook 2016, and the latest version (7.6) is from September 2023, so check that it works with your setup before you buy. It has been translated into most major languages, including English, Chinese, and German, which makes it useful for international users.

How SPAMfighter works

Like a guard, SPAMfighter checks all new emails that arrive in your inbox and tests them to determine if they are legitimate. When SPAMfighter finds an email that's not legitimate, it automatically removes it from your inbox and moves it to the junk folder. Should a spam email message slip through, you can simply mark it as spam with a single click, which automatically removes it from all other community members.

Furthermore, SPAMfighter offers live statistics for all messages, including your total inbox volume, spam-to-message ratio, and the total number of blocked spam attempts made in a specific period. These tools can be highly useful for businesses, but also for individuals who are curious about the amount of junk they receive.

Why choose SPAMfighter?

• Translated into most major languages, a good fit for non-English users.
• Community-based filtering removes a reported spam message for other users too.
• Live statistics show your spam-to-message ratio and blocked totals.
• Simple interface for Outlook, Thunderbird, and other Windows desktop clients.

10. Proofpoint Total Protection Spam and Malware Protection (formerly Hornetsecurity)

Price: Price on request

• Cloud-based
• Paid
• Enterprise-grade solution
• Best for Office 365 users

Proofpoint Total Protection Spam and Malware Protection (formerly Hornetsecurity, and before that ZEROSPAM) stands as a top-tier defense against cyber threats via email. Boasting a 99.9% spam detection and 99.99% virus detection rate, it's recognized as one of the best email filtering solutions on the market.

Proofpoint completed its acquisition of Hornetsecurity in December 2025, and the service is now sold under the Proofpoint Total Protection brand.

How Proofpoint Total Protection’s Spam, Malware & Phishing Filter works

The service effectively shields mail servers from DDoS attacks and phishing emails, utilizing multi-layered antispam mechanisms that block the bulk of spam emails upon arrival. This ensures that the quarantine remains uncluttered and user-friendly.

Additionally, the service comes equipped with intelligent protection mechanisms distributed across multiple data centers, safeguarding legitimate mail traffic even under the onslaught of large-scale DDoS attacks and waves of spam.

With a fully managed solution, Proofpoint handles the management, operation, and monitoring, with an SLA that covers availability and filter performance, and it stores incoming mail for up to 7 days if your own mail server goes down. For IT administrators, the system is intuitive, with essential information easily accessible and settings that can be quickly configured.

Why choose Proofpoint Total Protection?

• 99.9% spam detection and 99.99% virus detection.
• Fully managed, so the provider runs operation and monitoring for you.
• Multi-layered protection across several data centers, with mail stored for up to 7 days during outages.
• Tailored to Microsoft 365 environments.
• Adds broader security and backup features for business users.

11. MX Guarddog

Price: $0.25 per email address per month

• Cloud-based
• Per-address pricing, low-cost
• Most affordable per email address
• Suitable for small businesses and individuals

MX Guarddog is a cloud-based email spam filter that serves as the first line of defense against junk, computer viruses, malware, phishing emails, spoofed undeliverable notices, and Denial of Service attacks (DoS). When MX Guarddog detects a suspicious email, it moves it to quarantine and, at the same time, sends you a notification so you can decide what to do with it.

How MX Guarddog works

MX Guarddog uses TLS-based encryption and Perfect Forward Security (PFS) to keep your emails secure, and it also offers 99.95% SLA, which means that it shouldn’t be unavailable for more than a little over 4 hours per year, making it very dependable.

You can try MX Guarddog free for 30 days, with no credit card required. After the trial, it charges $0.25 per email address per month, so 100 addresses would cost $25 a month. You pay only for the addresses you use, with no limit on how much mail you receive.

Why choose MX Guarddog?

• No hardware, software, or client changes, since it runs entirely in the cloud.
• Blocks viruses, phishing, spoofed bounce messages, and denial-of-service attempts, not just spam.
• TLS encryption and Perfect Forward Secrecy, with a 99.95% uptime SLA.
• Quarantines suspicious mail and notifies you so you stay in control.

12. MailChannels

Price: Starting at $99.99/month (outbound filtering; inbound on request)

• Cloud-based
• Paid
• Enterprise-grade solution
• Best for fixing email deliverability issues

Businesses that offer web hosting or manage multiple email domains need a robust way to stop spam emails for both inbound and outbound mail. That’s exactly the solution MailChannels offers — protection from unsolicited emails and more for enterprise-level users.

How MailChannels works

One key benefit of MailChannels is the fact that it uses behavior analytics and response analytics to provide multi-layered spam, malware, and phishing protection. Also, unlike other spam filter programs, this service provides detailed message logs so users can easily figure out why a message was blocked or quarantined.

Unfortunately, MailChannels is not an inexpensive solution. Since it is made for enterprise users, you can’t get a plan for less than $99.99/month. That being said, this rate is actually quite affordable for users who manage inboxes that send and receive thousands of messages per month.

Why choose MailChannels?

• Protects both inbound and outbound mail, useful for web hosts and multi-domain setups.
• Behavior and response analytics give multi-layered spam, malware, and phishing protection.
• Detailed message logs show exactly why a message was blocked.
• Built for high-volume accounts sending thousands of messages a month.

13. Symantec Email Security.cloud

Price: Price on request

• Cloud-based
• Paid
• Enterprise-grade solution
• Offers advanced threat protection

Symantec Email Security.cloud is a cloud-based email security solution that offers many advanced features for users who need high levels of protection. Although research shows this solution costs more than some other options, it may be worth it if you need what it offers.

How Symantec Email Security.cloud works

One of the major selling points for Symantec Email Security.cloud is that it is programmed to handle advanced email attacks and protect against data leaks. If your email account ever contains financial documents or similar sensitive information, this could be exactly the spam filter you need.

📌 I also noticed that it provides security against phishing and spear phishing attacks.

Although most spam blockers will let you add individual email addresses to a blacklist, Symantec Email Security.cloud lets users lock IPs and Domains as well. Furthermore, you can find detailed reports within the app’s built-in dashboard, meaning you can look for patterns or make changes as needed based on the data you see.

Why choose Symantec Email Security.cloud?

• Designed for advanced email attacks and data-leak protection.
• Email Threat Isolation guards against risky links and attachments.
• Lets you block by IP and domain, not just individual addresses.
• Built-in dashboard with detailed reports to spot patterns.
• Covers Microsoft 365, Google Workspace, and on-premises, plus phishing-readiness training.

14. Apache SpamAssassin

Price: Free (open source)

• Server-hosted
• Free
• Best for admins who run their own mail server

Apache SpamAssassin is a free, open-source spam filter from the Apache Software Foundation. It is one of the oldest anti-spam tools still in active use. The latest version, 4.0.2, came out in August 2025.

How Apache SpamAssassin works

SpamAssassin gives each message a score. It runs many tests on the headers and the text: rule checks, Bayesian filtering, DNS blocklists, and shared spam databases. If the score is high enough, the message is marked as spam. Because it uses so many different checks, spammers can’t easily get past it by beating just one.

It isn’t an app for your inbox. You install it on a mail server and connect it to software like Postfix, Sendmail, or qmail. That makes it a good fit for IT teams and hosting providers, but not for someone with a Gmail or Outlook.com account.

Why choose Apache SpamAssassin?

• Completely free, with no per-mailbox fees.
• Combines rules, Bayesian filtering, and DNS blocklists in one scoring system.
• Rules live in plain text files, so admins can tune them.
• Works with most common mail server software.

Paid vs. Free Spam Protectors

Paid email spam blockers

I feel safe and protected with paid spam blockers because it's clear where the company’s income comes from. Paid solutions focus on quality and data security, so your emails and sensitive data won’t be leaked. Plus, they come with premium features that work for both businesses and individuals.

• Clean Email – Offers premium plans (and discounts!) for advanced inbox management and spam filtering.
• N-Able Mail Assure – A paid cloud-based anti-spam tool with high accuracy.
• SpamSieve – Requires a one-time license purchase.
• SpamTitan – Paid plans tailored for businesses.
• Securence – Offers paid plans for small businesses and nonprofits.
• Comodo Secure Email Gateway – A paid enterprise-grade security solution.
• Proofpoint Total Protection (formerly Hornetsecurity) – Premium cloud-based security for business users.
• MailChannels – Paid plans aimed at improving email delivery reliability.
• Symantec Email Security.cloud – An enterprise-grade paid security service.

Free anti-spam software

Free options provide basic spam protection, but they come with limits on features or email volume.

• MailWasher – Offers a free version with manual spam filtering capabilities.
• SPAMfighter – Has a free version for personal use (with ads).
• MX Guarddog – Free for 30 days with no credit card required.
• Apache SpamAssassin – Free and open source, for people who run their own mail server.

The Bottom Line

There's no single best spam filter, only the best one for your situation. The right choice still comes down to the two questions from the start of this guide: where your email lives, and how many people you need to protect.

• For a single personal inbox, a free or low-cost tool does the job. MailWasher if you want something free, SpamSieve on a Mac, or SpamBully and SPAMfighter on Windows.
• If you'd rather filter across all your devices without installing anything, a cloud inbox tool like Clean Email is the better fit.
• Small teams and businesses are usually served well by a cloud filtering service such as N-Able Mail Assure, or MX Guarddog when budget is the priority.
• If you run your own mail server, a gateway like SpamTitan, Securence, or Comodo Secure Email Gateway stops mail before it ever reaches a mailbox. If you can manage the server yourself, Apache SpamAssassin does it for free.
• For Microsoft 365, larger organizations, or anyone with compliance requirements, a managed suite like Proofpoint Total Protection or Symantec Email Security.cloud is built for that scale, and web hosts wrestling with deliverability have a more specific answer in MailChannels.

Whatever you choose, favor a tool that keeps itself current. Spam has become an industrial operation: senders now use AI to generate and vary messages at scale, and the response is moving upstream, with registrars and blocklist operators starting to take down entire clusters of related domains rather than chasing them one at a time.

Your inbox sits at the end of that chain, so the filter that protects it best is the one that updates automatically and matches how you actually use email, not the one with the longest feature list.

Related read: AI‑Powered Spam Filters: Gmail, Machine Learning & What’s Next