What is a 503 Service Unavailable Error?
[+How to Fix It]

4.5 min. read

Imagine the following scenario. A user is searching for something on Google and finds your website. They click on the link only to see a line that says: "503. Service Temporarily Unavailable."

What do you think they will do if this happens more than once? They'll think that your site is unprofessional and lose trust in your brand. The next time they come across your site, they'll skip visiting it and go to your competitor's.

So, what is a 503 error, and how can you fix it? Check out this post and learn what steps you can take to avoid losing potential customers.

What Does a 503 Service Temporarily Unavailable Mean?

There are dozens of HTTP response status codes in existence that explain the complicated relationship between servers, clients, and web applications. Some are redirects and requests, while others are errors. They include:

1xx status codes: Informational requests
2xx status codes: Successful requests
3xx status codes: Redirects
4xx status codes: Client errors
5xx status codes: Server errors

For example, you may come across a 301 redirect that says: "The requested document has been moved permanently." This status code is used when you're permanently replacing one URL for another.

Or, you can click on a link and get a 404 HTTP error. A 404 Not Found client error means that although the server is reachable, the specific page you're looking for is not

While the 4xx status codes are client errors, the 5xx status codes are server-side errors. There's the 502 Bad Gateway meaning that one server on the internet received an invalid response from another server. Or, the 504 Gateway Timeout which means your web servers aren't communicating with each other fast enough. Another frustrating error is HTTP error 500.

Specifically, the 503 Services Unavailable error indicates that everything is good with the request of the client, but the site's server is not available at the moment. As a consequence, your visitors will land on an error page, like the photo below.

How Can a 503 Error Appear?

The 503 Service Unavailable error can appear in different ways. The most common include:

HTTP Status Code 503
HTTP Status Code 503 Service Unavailable
503 Service Unavailable
Error 503 Service Unavailable
HTTP Error 503
503 Service Temporarily Unavailable
503 Error
HTTP 503
Service Unavailable - DNS Failure
503 Server error

It's also important to note that the 503 Service Unavailable error message can appear in any operating system and in any browser. Whether you're using macOS or Windows, Google Chrome or Safari, the error can show up in certain situations.

What Can Cause a 503 Error?

There are two leading causes of a 503 error. One, the server may be down for scheduled maintenance. Meaning, it hasn't crashed, but it's undergoing maintenance.

Two, the server may be rejecting requests due to overload. There may be a high income of traffic, and the server is rejecting a portion of the requests by serving them a 503 status code to maintain normal behavior.

The error 503 Service Unavailable is crucial for SEO. If you don't fix it soon, search engines will register it as a permanent issue and

de-index the page.

We're going to take a look at some troubleshooting tips and tricks to help you resolve the issue.

How Do I Fix Error 503?

Refresh the page

Although the HTTP 503 means that something is wrong with the server, it's usually only temporary. Wait a couple of minutes, and then click on the refresh button.

Restart your equipment

Another thing you can try on your end is restarting the networking equipment. Although it happens in rare cases, there may be a temporary issue with the equipment.

First, restart your computer/laptop. If this doesn't help, restart your modem, router, and other networking devices that may be the source of the issue

Faulty firewall configuration

It's also a possibility that a firewall configuration somewhere on the network to be preventing some traffic from getting through. It can deem requests from a content delivery network as an attack on your server and reject them. As a result, your visitors will see a 503 Service Unavailable error. Check your firewall configuration options to see if this is the root cause of the status code.

Refresh the server

Another thing you can try to get rid of the 503 Service Temporarily Unavailable error is to reboot your server. If you or your host can do it, restarting the server can do the trick. If your site is hosted on several different servers, you should restart all of them. If there's a blockage in the server chain that hosts your website, this should get it up and running.

Check for unexpected maintenance

It's also possible that your server is configured to undergo maintenance automatically. Many content management systems automatically download and install updates without any involvement on your end. When the server is down for maintenance, your visitors will be shown a 503 Service Unavailable message. This is more likely to happen if the server is slower or shared, that's why it's a good idea to use managed hosting. If you can access the server's configuration, check for scheduled automatic maintenance and disable these updates if you want to have complete control.

Remember to regularly perform monthly website maintenance to detect errors faster and resolve them on time. By regularly maintaining your site, your online business will attract and retain customers, offer useful content, and maintain good search engine rankings.

Check your logs

In some cases, checking your server logs can help you discover what's been causing the problem. There are two types of server-side logs, application logs and server logs. Application logs let you see the web pages your visitors requested, the servers it connected to, etc. Server logs give you information about the health of the hardware running your server. Check these logs to detect any issues.

Look through your website’s code

Your server might be answering requests from a content delivery network incorrectly due to an error in your site's code. To detect any error, look through your code or copy-paste the code into a development machine. By doing so, you'll simulate the exact scenario in which the error 503 happened and find out when things went wrong.

Get in touch with your host

If you're not confident with dealing with the error yourself and need help, get in touch with your host. Tell them the issue you're experiencing on the site and let them inspect what's the root cause of the http 503 error. If they discover that the error is on their end, they'll fix it as soon as possible. Or, they might see that the issue comes from your end and guide you on how to fix it.

Try again later

If you tried all of the tips and tricks below and didn't manage to fix the problem, then the last option you have is to try again later.

If it's an error with your hosting provider, they'll invest all their resources into fixing it. Don't forget to check back with the site regularly.

Final Word

It can get challenging to navigate the online world with all of its status codes, errors, and complications. To make things easier for you, we've written this comprehensive HTTP status code cheat sheet to help you understand the various types of status codes and what they mean. It'll come in handy for quickly referencing codes and discovering what each type of error implies and how you can fix it.