Required question

"* Indicates required question" means that every question marked with an asterisk (*) must be answered before the form or survey lets you submit it or go to the next page. If you skip one, the form stops you and shows a message such as "This is a required question" next to the empty field.

Questions without an asterisk are optional: you can leave them blank. The rest of this page explains what to do as the person filling in the form, and how to decide which questions to make required if you are building one.

If you are filling in a form

• Answer every question with an asterisk. The asterisk is usually red and sits next to the question title.
• If the Submit or Next button does nothing, scroll up. The missed question is usually highlighted in red with "This is a required question" or "This question is required".
• Check every page. In multi-page forms, each page checks its own required questions before letting you continue.
• If you don't want to answer, look for an option such as "Prefer not to answer". If there is none, the form can't be submitted with that question empty, so contact the form's owner.

What a required question is

A required question (also called a mandatory question or forced response) is a setting that blocks a respondent from moving on or submitting the questionnaire until the question is answered. Form builders mark such questions with an asterisk or the word "Required".

It guarantees that the field is filled in. It does not guarantee that the answer is true or thoughtful, and that difference is the whole trade-off.

What happens when you force an answer

When people are made to answer a question they would have skipped, they usually do one of three things:

• Answer anything. They pick the first option or type "ok", "." or "123" into a text box. The cell is filled, but the data is noise, and in a choice question a random click looks exactly like a real one.
• Leave. They close the tab, and you lose this answer and every answer after it. This raises the abandonment rate.
• Give the safe answer. On sensitive topics they choose the neutral or socially acceptable option, which shifts results through social desirability bias.

An empty answer is sometimes more honest than a forced one.

When to make a question required

• Screening and routing questions. If the answer decides which questions come next ("Are you a current customer?"), a skip breaks the logic.
• The key metric of the survey. If the survey exists to measure NPS or CSAT, that question should be required.
• Contact and identification fields you truly need, such as an email address for sending results or an order number.
• Quick, low-effort questions: yes/no, one of three or four options, a 1–5 rating.

When to leave a question optional

• Open-ended text questions. People with something to say will write it; forcing the rest produces filler.
• Sensitive topics: income, health, religion, politics, age when it isn't needed.
• "Nice to know" questions that the analysis can do without.
• Later questions in a long survey, where fatigue makes forced answers less reliable.

Practical techniques

• Required with a way out. For a sensitive question that you still need, make it required and add "Prefer not to answer". You can then tell a deliberate refusal from an accidental skip.
• Check the cost on a pilot. Run the survey with a small group before launch (see pilot study). If many people quit or type filler at one required question, reconsider it.
• Watch where people drop off. If drop-off clusters at one required question, soften the wording, make it optional or remove it.
• Tell people up front. A line such as "Questions marked * are required" at the start of the form sets expectations.

Required questions in SurveyNinja

In SurveyNinja, each question has a Required response switch in its settings, and the survey settings can make all questions required or all optional at once. Message and HTML blocks don't have the switch. A question can also get the Add "Prefer not to answer" option. Details are in Question Settings.

A required question that logic skips for a respondent isn't shown to them, so it doesn't block anyone. When someone leaves partway, their answers so far can be kept as incomplete responses (Standard plan and above), which shows which question people stopped at.