What Is A 503 Error And How To Fix It? Solutions With Causes Explained


Have you ever received a 503 error while using your website? The status code 503 – Service Temporarily Unavailable (service not available) is a response screen that shows the server when it can not process the request you are making at that precise moment.

This means that 2 seconds before may have responded correctly to another request, but right now yours has overloaded your website and is impossible to manage. If you test 5 minutes later, sometimes everything works perfectly, and the overload has been solved without the need to intervene. Therefore, as a web hosting company, we sometimes receive emails from very confused customers, which is normal.

Due to this intermittence in the appearance of the 503 status code, it is a very difficult error to explain and understand. Sometimes, when our Support technicians analyze the error, this is no longer occurring, with the consequent anger on the part of the client, who receives general indications but not a detailed analysis or a definitive solution.

What we usually ask in these cases is that you notify us as soon as possible, as soon as you perceive the error, or that you indicate the steps you take to reproduce it ourselves (sometimes the 503 occurs at the moment of publishing a post, for example). It is really, however annoying it is, the only way to analyze exactly what is happening. Of course, the management of this type of error depends on each provider, but we want to explain how it works in our case.

Next, we will give you all the possible details about what a 503 error is and how to solve it in case it ever happened to you or happened to you.

Why error 503 occurs?

error 503

It is important that you understand that error 503 is a security measure. For all the services of a server, there are security measures: maximum connections to a mail account, maximum file upload size via the web … It is logical and good that these limits exist because no server has infinite resources.

If a web were to consume resources insane and there was no 503, not only the web would fall but also the mail, databases … and even affect other users. And nobody wants to be affected by the misuse of server resources by a “neighbor.”

As we told you above, the error 503 appears when the request you have made overloads the web for some reason. The causes can be diverse, and we are going to tell them in order of frequency, taking into account what we usually find on the websites of our clients:

Cause # 1: You have a sudden traffic spike

You have shared a post that is the cane, you are giving away something, or the link to your website has been published in the screen or on the cover of the Brand, for example, Congratulations! There are so many people trying to see your website at the same time that the requests are unsustainable. You have mixed the resources with potatoes, and so there is no server to hold so that your website has stopped being available and shows almost everyone (almost all the time, live the intermittency we were talking about) a 503 error.


Get in touch with your hosting company, and they will do everything possible to put your website online once more so you can continue enjoying the success and drinking daiquiris with a little umbrella.

Note: A lot of attention to when the traffic peak is not sudden, but perfectly predictable. Do you sell spruce and it’s Christmas in 15 days? Rubber crabs and the time of hippest festivals? People will go en masse to your website, and you know it: plan! Get in touch with your hosting provider in advance and (at least in our case) we will advise you as much as possible so that you get your website on wheels during those specific days. Once that peak has passed, you can return to your usual resources.

Cause # 2: An attack causes the peak of traffic

There are people with very bad milk who has nothing to do but play to attack websites. The simplest solution in those cases was blocking the file in question (which, anyway, very few people use), but each attack is different.


If it is detected that someone is attacking your website, your hosting provider should block it so that it can not continue doing so.

Cause no 3: Your project has grown and your needs too

Cause # 3 is very similar to cause # 1, but instead of being due to a sudden and temporary problem, it is permanent. It means that your website has grown since you started, that now you have many more visits that consume the resources you hired in your day. You need to expand your service to accommodate all those simultaneous requests.

Again, congratulations! After all, what you were looking for when you started the web is precisely what you have achieved: the number of visitors interested in what you have to say. You will need to invest a little more for the project to go ahead normally, but surely you will not mind doing it because you are succeeding, right? Yes, be careful in case you are demanding too many resources, for example, because you have an exaggerated number of accounts hosted in the same shared plan. It is not convenient to abuse!


As in the previous case, contact your hosting provider. They will advise you on the service you need to cover your new needs.

Cause no 4: There is a problem of programming in your web

Unfortunately, it is possible that the error 503 of your website is not directly caused by the success of it or by an attack that we can easily identify from here. The 503 errors in WordPress are a fairly common phenomenon, and there are parts of this application that are not as optimized as they could be.

What does this mean?

That WordPress is a CMS prone to causing 503 errors or very slow loads of the web. It is a job because today is the most used application in the world to create websites and, besides, it is very comfortable! Something bad had to have.


Each case is a world and must be analyzed separately. However, we always recommend customers using WordPress to install the WP Super Cache plugin. We have verified that, without a doubt, it significantly reduces the number of SQL queries that WordPress needs to perform and, therefore, your website works in a much more fluid way.

Note: You have to install this plugin in each and every one of the WordPress that you have hosted in your hosting. This is because a single poorly optimized WordPress can affect the rest of the webs hosted in the same hosting plan, producing slowness in all of them.

If you have a problem during the plugin configuration process or you see that it is not working as it should and you are our client, contact the Support team to review and correct the configuration. If by chance WP Super Cache is not compatible with your installation for any reason (for example, by the template you use), write us, and we will also indicate alternatives for this case. There are always options!

What if the installation of the plugin is not enough?

error 503 solution

In that case, you’ll have to have a little patience. As we explained at the beginning of the post, to analyze the problem the technicians of your hosting provider need to be able to reproduce it, which is not easy when it is an intermittent error that takes place when taking concrete steps. With your help, you can find the fault and solve it. In our case, we also want you to be able to work and enjoy your website and be happy with its operation, so we will do everything possible to achieve it.

If you have been left with doubts and you want us to try to answer them, you can leave a comment. Have you ever suffered a 503 error? Do you know what the cause was and you managed to solve it?