How to mark required fields in forms

Torresburriel Estudio
3 min readMay 27, 2021

A topic that is often debated in UX is whether or not to mark the mandatory fields of a form. Nielsen Norman explains that they get asked about it a lot, and their answer is always yes.

Designers tend to think that marking every required field is repetitive, unattractive and can become overwhelming for the user. So they adopt one of two strategies:

  1. Place instructions at the top with “All fields are mandatory” or “All fields are required unless indicated”.
  2. Mark the optional fields, because these are fewer.

However, what is wrong with these assumptions?

  • People don’t read the instructions at the beginning of the forms. Users don’t usually read instructions, specially if they only appear at the top of the form. Also form fields seem self-sufficient, so why should they read more?
  • People read the instructions, but they forget them. Users forget the instructions because they have to fill in the form, and if it is too long or they get interrupted during the process, they will forget them more easily. Filling out the form is hard enough, so why would you add another extra difficulty?
  • People have to scan the form to determine whether the field is required. Even if you give instructions the results will be the same, users will ignore the instructions or forget them. Users will scan all the information and deduce whether the field is required or not.

To avoid these problems it is best to mark all mandatory fields.

How to mark the required fields?

There are two options: with asterisks or with “required”. The asterisk has become a convention and everyone knows what it means. It needs little space, so it is a good option to use.

It makes no difference to put the asterisk before or after the label. However, if it is set before, the eyes detect earlier which fields are mandatory at first glance.

Do you have to mark the optional fields?

Although it is not mandatory, marking the optional fields eases cognitive load on users. If a field does not have a description, the user will have to guess that the field is optional from the rest of the fields marked as mandatory.

What should be done with login forms?

Login forms usually have two mandatory fields, username and password. In this case you have two options, either you mark the fields with an asterisk, or you assume that users already know that in a login form they have to enter all fields. You can skip the asterisk if you want, because users already know what they have to do.

However, it is risky not to mark required fields in a registration form with an asterisk. Forms are not enjoyable. They require a lot of work. In fact, many forms are abandoned because they are too difficult to fill in.

To increase the chances that a form will be filled out correctly, designers and product managers should think about making users do as little work as possible. Marking mandatory fields is a simple way to do it.



Torresburriel Estudio

User Experience & User Research agency focused on services and digital products. Proud member of @UXalliance