How to Stop WordPress Comment Spam: Top 7 Methods

If you’ve ever managed a WordPress site, you know just how frustrating comment spam can be. It clutters up your site with irrelevant content and can even make your site look like a spam site if comments are automatically approved. On top of that, working through hundreds of spam comments also wastes a ton of your or your employee’s time.

Thankfully, there are plenty of ways to manage the issue. Some are as simple as turning on a few WordPress settings, like requiring user registration to post. Others require installing plugins — like adding CAPTCHA challenges — but more comprehensively block bots.

Ready to finally clean up your site and stop WordPress spam comments for good? This guide will walk you through the top 11 methods to effectively combat WordPress comment spam.

The negative impact of WordPress comment spam

WordPress comment spam may just seem like a minor annoyance. Sure, it clogs up comment sections and drowns out genuine conversation if it is accidentally accepted and published, but how bad can it be? After all, most comments aren’t auto-approved so visitors are unlikely to see them. 

But the truth is that spam comments can have a bigger impact on site admins than you might expect.

• Wasted time on moderation – Reviewing and filtering spam comments takes up valuable time, which could be used for more productive tasks like site updates, content creation, or user engagement. Without an efficient solution, admins are left spending hours dealing with an influx of irrelevant spam comments. 
• Strained user engagement tools – Many plugins and themes with engagement features, like comment rating or reply threading, can start to malfunction or slow down under a flood of spam. Admins may experience performance issues not just in comment moderation but across other engagement features. 
• Poor user experience – People check your comment sections because they want to engage in conversation. When you have comments set to auto-approve, then you’ll be left with a ton of spam visible on your website. If your visitors find nothing but useless comments full of harmful links, they’ll immediately be turned off. A comment section full of spam makes your site look unprofessional and can subtly damage your reputation. 
• Damaged SEO –Even if you didn’t post the spam links, Google expects site admins to maintain quality control on all content, including user comments. If spammy links make it past your filters, Google could potentially penalize your site, impacting your rankings and lowering visibility. Admins need to prevent harmful links from entering the site in the first place to protect their SEO.
• Security vulnerabilities – Although spam comments themselves may not pose a direct threat, they can open doors to more serious risks. Many spam links lead to phishing sites or malware, and even a minor slip in moderation could expose both you and your visitors to security threats. Staying vigilant is a must.
• Resource strain – Spam bots can increase server load by posting thousands of spam comments. This affects site performance, causing slower load times, and can also increase hosting costs if the spam overloads your server. Admins must actively manage or prevent spam to avoid these resource strains.

Even if you aren’t dealing with tons of spam yet, it’s best to be proactive before you get hit by the flood.

Where does spam come from?

Most WordPress spam comments are automated by bots, looking to direct traffic to third-party sites. There, they make money off ads or through affiliate links. Some also intend to boost their spam site’s SEO by farming external links from highly-ranked websites.

Spammers target WordPress websites specifically because of the platform’s popularity and consistent underlying design between sites. Most WordPress blogs have a comment section, and bots are programmed to find and target these.

While some WordPress spam comments are left by humans being paid to post links on blogs, this is a small percentage of spammy traffic. Since the bulk of spam comes from bots, methods that target bot traffic, like CAPTCHA challenges, work well at stopping it.

Now let’s get into all the ways to stop WordPress comment spam.

Method 1: Using a CAPTCHA solution to stop comment spam

One of the most effective ways to stop WordPress comment spam is by using CAPTCHA. You’ve certainly seen a CAPTCHA challenge for yourself before; distorted text, identifying elements of an image, and solving simple logic puzzles are all ways to stop bots in their tracks.

Some types of CAPTCHAs are even simpler, identifying bots from humans by how quickly they click a single button or by suspicious traffic markers. Others are entirely invisible to visitors, so they never disrupt the user experience unless there are signs the visitor might be a bot.

While not 100% foolproof, CAPTCHA will stop most automated spammers in their tracks.

How to install and set up CAPTCHA 4WP

CAPTCHA 4WP is the best way to add CAPTCHA challenges to your website. It integrates seamlessly into your site’s comment forms, login pages, and other forms on your site.

It’s also extremely flexible, working with several different types of CAPTCHA, including Google ReCAPTCHA V2, V3, hCAPTCHA, and invisible varieties. It also comes with a failover feature, which means that even if a real human accidentally fales the test, they aren’t locked out for good.

And since it’s so easy to set up, anyone can use it. 

Here’s how to set up CAPTCHA 4WP.

1. Install the CAPTCHA 4WP

WordPress comment spam can be stopped using the free version of CAPTCHA 4WP in many situations. It supports multiple types of Google reCAPTCHA out of the box and is very easy to set up. To install this, go to Plugins > Add New Plugin. 

However, if you’d like more advanced features, like GDPR-compliant CAPTCHA using hCAPTCHA or Cloudflare Turnstile, you can install the premium version. This also includes WooCommerce support and support for adding CAPTCHA to third-party form plugins like Gravity Forms and WPForms. 
We’ll be using the premium version below, but you can follow most of the steps with the free version too. Once purchased, upload the zip file in Plugins > Add New Plugin > Upload Plugin and enter your license key.

2. Configure the plugin

Once installed, visit CAPTCHA 4WP > CAPTCHA Configuration. The wizard will pop up, walking you through setting up the plugin.

3. Pick the type of CAPTCHA you want

You can select from a few different CAPTCHA options. Note that hCAPTCHA and Cloudflare Turnstile require a premium plan. Then click Next.

4. Input your Site Key

Whichever CAPTCHA type you pick, you’ll need a Site Key. Check this guide to learn how to get reCAPTCHA keys, how to get hCAPTCHA keys, or how to get Cloudflare Turnstile keys. You’ll also get a secret key you’ll enter in the next step of the wizard, and this pair allows CAPTCHA to work on your site.

5. Finish setup

Once you’ve entered your site and secret keys, click Finish to complete the wizard.

After that, CAPTCHA should be working on your website. Now we just need to add it to your comment forms.

6. Configure CAPTCHA 4WP

On the same page (CAPTCHA 4WP > CAPTCHA Configuration), you can set up how your CAPTCHA messages look and their sensitivity if using a score-based system.

7. Add CAPTCHA to your forms

Finally, to actually place the CAPTCHA challenges in your forms, head over to CAPTCHA 4WP > Form Placements and tick the boxes for each location. In the premium version, you can add CAPTCHA to third-party forms, WooCommerce, and more. For now, we’ll only be selecting Comments form.

While this is a great method for stopping automated spam, it works even better when combined with other methods.

Method 2. Require user registration

Requiring users to register before they can comment on your posts is a straightforward and effective method to cut down on spam. When only logged-in and verified users can post, it’s harder for bots to flood your site.

1. Open your dashboard and navigate to Settings > Discussion.
2. Look for the Other comment settings section. Tick Users must be registered and logged in to comment.
3. Click Save Changes.
4. If you have CAPTCHA 4WP installed, make sure you go to CAPTCHA 4WP > Form Placements and tick Registration form to add CAPTCHA to your account creation forms too.

On the other hand, many spam bots are coded to get around this requirement, since it’s easy to make an account with a fake email. So you may just be unnecessarily limiting legitimate readers from leaving comments.

If you’re experiencing an influx of spam, it’s not a bad idea to turn on this setting and see if it helps, but it’s definitely not something you should rely on alone.

Method 3. Blacklisting keywords and phrases

Blacklisting can be a great option for filtering a portion of the spam comments submitted on your site. Blacklisting allows you to filter out spam based on common spam words and phrases, like “buy now”, “click here”, and so on.

As you get more spam comments, you’ll get a sense of what topics they tend to post about. Many spam comments are exactly the same, so once you pick up on common patterns, you can blacklist the words your legitimate commenters are unlikely to ever mention.

Here’s how to set it up:

1. Go to Settings > Discussion in your WordPress dashboard.
2. Look for the Comment Moderation section. Enter any words, phrases, emails, IP addresses, and so on that you want to block. When comments that fit the criteria are submitted, they’ll be sent to the moderation queue in Comments.
3. Now scroll down to the Disallowed Comment Keys section. When people use words, phrases, and so on typed in this box, their comments will be sent directly to the trash and deleted in 30 days.
4. Click Save Changes.

You have to be careful with this method since being too restrictive can result in genuine comments being deleted and more work having to approve them. For example, a keyword like “free” might be a common part of spam messages, but there are plenty of legitimate reasons for actual commenters to use it.

That being said, there are many words used by spammers that won’t ever be used by real commentors. By blocking these, you can effectively stop a portion of the comment spam you get without ever having to moderate it.

Method 4. Use a honeypot

A honeypot is an effective, invisible method to trap spam bots without affecting your typical users. It works by adding a hidden field to your comment form that is invisible to human visitors but visible to bots. Since bots often automatically fill in all form fields, they unknowingly complete this hidden field, triggering the honeypot and flagging the submission as spam.

While this form is typically hidden, they are sometimes visible. You may have seen an extra option on some forms labeled “leave this form blank if you’re not a bot”. It’s the same concept.

To add a honeypot to your site, you’ll need a form plugin. Most major form plugins will allow you to add a honeypot, including Contact Form 7 and Gravity Forms. The honeypot technique is a fairly effective, low-maintenance option, but it’s not foolproof. Bots have long been coded to detect and ignore hidden fields. The effectiveness depends on how sophisticated the spam bots you’re targeted by are and how well your form plugin circumvents these bots.

So, it can be worth combining this with other methods, like CAPTCHA. If you do decide to use CAPTCHA 4WP, then know that it is compatible with all the popular choices: Contact Form 7, Gravity Forms, Ninja Forms, and plenty more. But it also allows you to add CAPTCHA to any other type of form too.

Method 5. Geolocation blocking

Sometimes a flood of spam can come from particular geographic regions, and blocking those regions from submitting comments may be a good move. This can be a temporary or permanent measure, depending on whether you would like to prevent submissions from specific regions by default.

This can have major user experience implications depending on what countries you end up blocking. Effectively banning certain people from leaving comments may be a bad move if you’re looking to foster a global audience. However, if your website is only intended for users from a certain region, it’s not a bad idea.

You can use geolocation tools to identify the geographic location of users based on their IP address. However, this can be a lot of work. CAPTCHA 4WP includes geoblocking in the premium version of the plugin. Here’s how to set it up.

1. Install CAPTCHA 4WP if you haven’t already through Plugins > Add New Plugin. See above for step-by-step instructions on how to set up the plugin.

2. Navigate to the CAPTCHA 4WP > Settings page. Click the Integrations tab.

3. Follow the link to IPLocate’s login page. Sign up for the service – it’s free for up to 1,000 requests per day. 

4. Once you have an IPLocate API key, go back to WordPress, enter it in the IPLocate API Key box, and click Save Changes.

5. Head over to CAPTCHA 4WP > Form Placements and scroll down to the Do you want to block/allow protected form submissions based on a user’s location? section.

6. Enter the ISO country codes you want to either whitelist (all other countries are blocked) or blacklist (only those countries are blocked).

7. Click Save Changes.

Now commenters from outside the allowed countries (or within the denied countries) won’t be able to leave comments.

While spammers can and do use VPNs to hide where their traffic is really coming from, you can use geolocation blocking as a reactive measure if you notice a lot of spam coming from certain regions.

Method 6: Add a firewall

A WordPress firewall serves as a protective barrier between your website and potential threats, including malicious bots that generate spam comments.

A firewall is an effective spam deterrent since it detects and blocks bots before they ever get to your comment form. They do this by analyzing web traffic and detecting bots through suspicious network patterns or known IPs that have been blacklisted.

That being said, as is the case with other controls on this list, they’re far from foolproof. By combining a firewall with other security measures, you’ll have a better chance at stopping more comment spam.

There are plenty of WordPress plugins and services that offer web application firewalls that detect and block malicious traffic. You could also set up a network firewall, though this is more difficult and expensive.

Platforms like Cloudflare and Sucuri can help you easily install a firewall that will put a stop to most spam bots.

Method 7: Disable comments on posts

If you don’t want any user interaction on your site, disabling comments is a good and quick option to prevent spam comment submissions. This is certainly the most effective way to get rid of spam forever, but it comes with the obvious drawback that you won’t be able to get comments or encourage discussion anymore.

If you feel the ability to leave comments isn’t worth having on your website, it may be time to just shut off the comments section altogether.

This can also serve as an effective, temporary measure, either to wait out the spam or while you work on implementing these other methods. Or if you find that certain posts are attracting the most spam, you can shut off comments for those individually.

If you want to disable comments on individual posts, just look for the posts in Posts > All Posts. Hover the post, click Quick Edit, and untick Allow Comments. Then click Update. Repeat for each post or use the Bulk Actions dropdown to do this for multiple posts at once.

If you want to disable comments site-wide, here’s what to do.

1. Navigate to Settings > Discussion.

2. In the Default post settings section, untick Allow people to submit comments on new posts.

3. Scroll down and click Save Changes.

4. This will stop new posts from having comment sections, but your old posts will still have them. Let’s fix this by going to Posts > All Posts.

5. Click the checkbox at the top of the list, next to Title, to select all. Then click the Bulk Actions dropdown, select Edit, and click Apply.

6. This will open up a menu on the same page. Look for the Comments dropdown on the far right, select Do not allow, and click the blue Update button.

Now, all your posts will have comments closed until you decide to open them again. If you ever do want to do that, just follow the same steps but turn comments on new posts back on and change the comments on existing posts to Allow.

Other methods to reduce spam comments

When it comes to taming comment spam, every extra measure counts. By now, you’ve seen some powerful ways to keep spammy content at bay. However, for whatever reason, they might not be for you. Luckily, there are a number of other steps you can take.

The steps below won’t block spam comments outright, but they might help reduce the number of spam comments you get. These small steps reduce spam and help you maintain a more welcoming, professional space for real, engaged readers. They can even be used on conjunction with some of the other methods mentioned above, for even better results.

1. Enable comment moderation

Enabling comment moderation is the standard these days, but it’s still an important one to mention. If you don’t want to take any risks for what shows up on your site, enabling comment moderation is the way to go. When you turn on this setting, you’ll need to manually review all comments and approve them before they show up on your site.

This works really well paired with CAPTCHA. Use CAPTCHA to cut out all the junk that makes moderating comments take forever, and manual moderation will let you catch any stragglers that leak through.

Here’s how to turn on comment moderation (if it’s not enabled already), no plugins required:

1. Visit your WordPress dashboard and navigate to Settings > Discussion.

2. Look for the Before a comment appears option. Tick Comment must be manually approved.

3. You can also tick Comment author must have a previously approved comment. Commenters will not need to have their content moderated more than once if you tick this box.

4. Click Save Changes when you’re done.

Once this setting is on, you’ll need to manually approve all comments on the Comments page. Look for Pending.

This is one of the most foolproof ways to stop spam from getting onto your site. The only issue is that it’s not really viable for larger sites, even with spam filtered out. When you get hundreds of legitimate comments per week or more, you’ll need to turn to other methods.

2. Limit or disable links in comments

One of the primary reasons spammers target WordPress comment sections is to insert links and get free traffic. Limiting links, or disabling them entirely, can effectively reduce your site’s appeal to these spammers.

Many spam comments contain multiple links to different websites, but this isn’t always true – some have only one. It’s most effective to just stop people from posting URLs entirely. While not all spam comments involve links (some direct you to emails or phone numbers instead), the majority do.

Some users may get frustrated when they try to share genuinely helpful links and have their comments disappear, so it’s up to you how restrictive to make this setting. You can manually approve legitimate comments through the Comments page.

You’ll find this setting in Settings > Discussion. Look for the Comment Moderation section, then Hold a comment in the queue if it contains x or more links. Set the number of links users can post before their comment is hidden.

Don’t forget to click Save Changes.

Blocking links doesn’t always work, since spammers can get around it by posting URLs broken up with spaces or symbols. While not as enticing as a clickable hyperlink, it still means spam is showing up on your site. You should rely on other methods along with limiting links.

3. Disable comments on old posts

Moderating comments on hundreds of posts can quickly get out of control, and you may get to a point where the only people commenting on your older posts are spam bots. When the time spent moderating overtakes the few legitimate comments you get, it may be time to disable comments on your older posts.

Spammers may even target older posts since they tend to be less actively moderated despite potentially getting just as much traffic as your new posts. Rather than shutting off comments entirely, you can just turn them off once posts get too old, and users tend not to comment much on them anyway.

WordPress allows you to set a time limit, after which the comment section on a post is automatically closed. You can find this option in Settings > Discussion.

Look for Automatically close comments on posts older than x days and enter how many days you want your comment section to stay open for. The default is 14 days (two weeks) but you may want to keep comments open for a week, a month, or several months.

This technique lets you focus on moderating a handful of new posts rather than dealing with dozens of comments across your entire site. But it can result in a lot less engagement, so keep that in mind.

4. Disable trackbacks and pingbacks

Trackbacks and pingbacks are legacy features in WordPress that allow other blogs to notify you when they link to your content. While it’s nice to be able to network with other bloggers, these features are frequently abused by spammers who use them to flood your website with unwanted links.

Trackbacks are manual notifications sent from one website to another when content is referenced. For instance, if someone writes a blog post and includes a link to your post, they can send a trackback to notify you about the link with an excerpt of the content.

Pingbacks are similar but automated; when you link to another post on a blog where pingbacks are automated, they receive a notification and the pingback is displayed as a comment on their post.

Both of these let other blogs “ping” your site, notifying you that they’ve linked to your content. Unfortunately, spammers exploit this by spamming links to legitimate blog posts on their illegitimate websites, filling your comments section with unwanted spam.

They’re basically using your website to give free traffic to their spam website, which is why most people disable trackbacks and pingbacks.

Disabling this can be a bit involved, so here’s what you need to do.

1. Navigate to Settings > Discussion in the WordPress dashboard.

2. Look for the first Default post settings section. Untick Allow link notifications from other blogs (pingbacks and trackbacks) on new posts to disable trackbacks and pingbacks.

3. This will turn off trackbacks and pingbacks on all new posts, but you still need to turn it off for existing posts. Go over to Posts > All Posts.

4. Click the checkbox at the top of the list, next to Title, to select all. Then click the Bulk Actions dropdown, select Edit, and click Apply

5. This will open up a menu on the same page. Look for the Pings dropdown on the far right, select Do not allow, and click the blue Update button.

Now, all current and future posts will have trackbacks and pingbacks disabled.

Trackbacks and pingbacks are both heavily abused by spammers, so turning them off can be a good way to keep your comments clean.

Stop spam with CAPTCHA and other methods

Comment spam can be a persistent problem for WordPress users. It’s best to be proactive and start putting anti-spam measures in place now, rather than after it’s become a major problem.

It’s also best to take a multi-layered approach. Despite what any plugin or solution may promise, no one method is 100% foolproof. Spammers are constantly evolving, but when you put enough barriers in the way, they’re likely to leave your site alone and go for easier targets.

Each method offers its own benefits and drawbacks, so try out a variety of different ones to find the right combination that works for your site.

Ready to get started with CAPTCHA 4WP and kill spam on your site for good? Try the free version or buy the premium version of CAPTCHA 4WP.