Skip to content

How to Spell Questionnaire (Common Mistakes)

  • 5 min read

Correct Spelling For Questionnaire

✅ Correct
questionnaire standard noun
❌ Wrong
questionaire missing “n”
❌ Wrong
questionnare missing “i”
❌ Wrong
questionare missing letters

In edited English, questionnaire keeps the double “n” and the -naire ending. ✅Source

Questionnaire looks familiar, yet the spelling still trips people up because the ending sounds likenare.” The key is the -naire ending plus the double “n” in the middle, which is exactly where most misspellings happen.


What The Word Refers To

A questionnaire is a set of questions presented as a written form, usually to collect information in a consistent way. In everyday writing, it often sits next to words like survey or feedback, but the spelling stays the same.

Part Of Speech
Noun (countable) with the same core meaning across contexts.
Common Pairing Words
Customer, medical, registration, research.
Typical Verbs Around It
fill out, complete, submit, review.

Where The Spelling Comes From

Questionnaire is a borrowing from French, built around the verb questionner (“to question”). Merriam-Webster also lists 1890 as the first known use in English, which matches the late-19th-century feel of its spelling. ✅Source

The ending -naire looks “French” because it is, and it behaves like a compact label ending in English: it turns the base idea into “the thing related to it.” With questionnaire, the base idea is question, and the result is the question-form people respond to.

The Part That Causes Misspellings

Most errors happen in the middle and the ending: ques + tion + naire. People hear the last part as “nair” and silently drop a letter, which is how questionaire shows up so often.

questionnaire
ques • tion • naire
      ↑      ↑
   double n  -naire

One Detail That Matters: the double “n” sits right before aire. That pairing (nn + aire) is the visual “signature” many writers look for when they’re checking the word.

Common Misspellings You’ll See

These variants tend to repeat in emails, forms, and reports. Each one is understandable, yet questionnaire is the only standard spelling in English, with the double “n” and the -naire ending intact.

  • questionaire (drops one “n”)
  • questionnare (drops the “i” in -naire)
  • questionare (simplifies the middle and the ending)
  • questionnair (drops the final “e”)
  • questionnaire (keeps nn + -aire)
Correct Vs Common Wrong Spellings
Form Status Why It Feels “Right” What The Standard Spelling Keeps
questionnaire ✅ Correct Matches the French-looking ending and the common “-aire” pattern. Double “n” + -naire together.
questionaire ❌ Wrong Sounds like kwes-chuh-NAIR, so one “n” disappears. The standard form keeps nn before aire.
questionnare ❌ Wrong The eye treats -naire like a simpler “-nare”. The standard form keeps the i in -naire.
questionare ❌ Wrong It follows familiar “question + are” visual shortcuts. The standard form keeps the double “n” and the full -naire.
questionnair ❌ Wrong The final silent “e” gets dropped in quick typing. The standard form ends with -aire, not -air.

Questionnaire Vs Questioner

Questionnaire is the document or form. Questioner is the person asking questions. They share the same root, yet they land in different roles, which is why mixing them up changes meaning, not just spelling.

Questionnaire

  • thing A written set of questions.
  • Often used with fill out and complete.
  • Plural: questionnaires.

Questioner

  • person Someone who asks questions.
  • Often appears in interviews, debates, and Q&A settings.
  • No -naire ending because it’s not a form.

Pronunciation And Spelling Map

Pronunciation is a big reason questionnaire gets misspelled: the ending is typically heard as “nair.” The American Heritage Dictionary gives the respelling kwĕs′chə-nâr′, which lines up with that sound and explains why questionaire feels tempting at a glance. ✅Source

Spelling Features That Stay Stable

  1. ques at the start is consistent, with “question” as the base.
  2. The middle keeps a double “n” before the ending.
  3. The ending is -naire, not -nare and not -nairee.
  4. The word ends with -aire, including the final e.

Examples In Real Writing

These examples keep questionnaire in natural contexts, where the double “n” and -naire ending matter most for clean, professional spelling.

  1. Please complete the questionnaire before your appointment.
  2. We attached a short questionnaire to collect customer feedback.
  3. The onboarding questionnaire asks about preferences and contact details.
  4. Each participant received the same questionnaire to keep the results comparable.
  5. The registration questionnaire includes a section for optional comments.

The plural is questionnaires, and it’s formed in the plain English way by adding -s. Collins also flags that writers should be careful with the spelling of questionnaire, which fits the reality of how often questionaire shows up in drafts. ✅Source

Related forms keep the same core: questionnaire-based (as an adjective), questionnaire item (a single question), and questionnaire response (an answer set). The spelling stays questionnaire even when it’s hyphenated or used as a modifier.


FAQ

Common Questions About Questionnaire

Is “questionaire” ever correct?

No. The standard spelling is questionnaire with a double “n” and the -naire ending.

What is the plural of “questionnaire”?

The plural is questionnaires. The -s is added to the full spelling, keeping -naire intact.

Why does “questionnaire” have two n’s?

The spelling holds nn right before -aire. That “nn + aire” cluster is the part most people simplify when typing quickly.

Is a questionnaire the same thing as a survey?

They’re closely related, yet not identical. A questionnaire is the set of questions; a survey often refers to the whole process of collecting and analyzing responses.

What’s the difference between “questionnaire” and “questioner”?

Questionnaire is the form. Questioner is the person doing the asking. The -naire ending points to the document, not the person.

Is there a simple pronunciation cue that explains the spelling?

Many speakers say something close to “kwes-chuh-NAIR,” which nudges people toward questionaire. The spelling still stays questionnaire with nn and -naire.