In this article, I'll show you (probably) the best WooCommerce checkout validation plugin. You will be able to validate checkout fields - both default and the custom ones.
WooCommerce Checkout Validation Plugin for you
First of all, you need a plugin for checkout fields, because WooCommerce lacks a crucial thing which is checkout fields management. The plugin should give you an option to:
- change fields' names,
- change the order of fields,
- create new, custom fields.
We created a plugin that has all the features I have listed above. Furthermore, you can download it for free.
Our Flexible Checkout Fields plugin has WooCommerce checkout validation features built-in.
Also, over 40,000 stores worldwide use the Flexible Checkout Fields plugin on a daily basis!
Look at reviews:

Sounds like a good piece of code, right? :)
WooCommerce Checkout Validation by Flexible Checkout Fields
Use the built in validation rules or create your own. Manage fields, create conditional rules. Master your checkout fields!
Download for free or Go to WordPress.orgYou'll love this simple interface
We wanted our plugin to be as easy as possible. We decided to make it as much WordPress-style as we can.
You will configure your checkout fields in a second because the design does not get in your way, but helps you achieve your goals smoothly. This design will be well-known for you as a WordPress/WooCommerce user.
As you see, Flexible Checkout Fields is not only a WooCommerce checkout validation plugin. It has much more valuable features.
Checkout validation at its finest
First of all, you have to know that WooCommerce has built-in fields validation. It can validate email, phone number or postcode.
Flexible Checkout Fields lets you use this default validation rules on your custom checkout fields. Furthermore, you are able to use your own validation. Therefore, our users praise Flexible Checkout Fields as an efficient WooCommerce checkout validation plugin!
How to configure WooCommerce checkout fields validation
You can configure validation right in the field settings:
There is a select box so you can simply select an option that you want.
None
This is a default option for new fields. No validation rules will be checked.
Default Validation
The field will have default validation turned on as a result of this option. The default validation works with:
- Email field
- Phone field
- Postcode field
Let's enter an invalid email address on the checkout page:
You'll see an error message as a result:
Default WooCommerce fields work like that.
Email, Phone or Postcode
You can use validation from these fields in your custom fields.
Try it! Create a single line text field and add a validation to it. Email validation maybe?
Next step: enter an invalid email addresses.
Finally, check out the result:
Seems like it works as expected.
You can use phone and postcode validation in your custom fields in the same way.
Custom validation rules for developers
You can also add your own custom validation to Flexible Checkout Fields. If you are a developer or familiar with hooks and editing PHP code, it will be very easy. Learn how to add custom validation to WooCommerce →
Your custom validation will show up in the Validation select box as a result:
Are you ready to use checkout field validation in your store?
Finally, you have learned how to configure validation in the Flexible Checkout Fields plugin. This is a very powerful tool. However, Flexible Checkout Fields is not only a WooCommerce checkout validation plugin. You can use it to manage fields (including labels, placeholders or CSS classes), rearrange them or add new custom fields.
I hope this knowledge will help you with your store! If you have any questions, just use a comments section below.
PS. Maybe our WooCommerce Checkout Step-by-step Guide will be interesting for you?