Deal form cut to 3 required fields, rest hidden: +26% conversions
Commentary byLiftArchiveOur analysis, not theirsCutting a travel deal enquiry form from eight required fields to three, and hiding the other five behind a dropdown, raised form conversions by 26%.
InsightWhale ran this test for a destination travel company, and it was published as a Convert case study.
A second version that showed the optional fields openly did no better than the original.
- Deal page form conversions: +26% for the version with optional fields hidden.
- The other challenger (three required fields, with all five optional fields visible below them) converted about the same as the original.
- Bounce rate did not change across any version, so the gain came from people already on the page finishing the form.
- Convert reported a 100% confidence score after 45 days and 54,697 visitors split three ways.
The change
Eight required fields become three, with five optional fields hidden in a dropdown
Simplified mockup drawn by LiftArchive from the shared screenshots.
Control
The deal page form had eight fields, all mandatory, laid out in several columns.
Variant
The winning version used a single-column layout with three required fields. The five optional fields were hidden under a dropdown the visitor could open if they wanted.
Why it likely won
Our reading of the result, not the practitioner's claim.
- Fewer visible fields made the form look quick to finish, especially on a phone. About 72% of the traffic was mobile.
- Marking fields optional was not enough. When all eight were still on screen, the form looked just as long as before.
- A single-column layout is easier to scan and fill in on small screens than a multi-column one.
Caveats: The test ran for 45 days with 54,697 visitors across a three-way split, mostly on mobile. The winner also changed the layout to one column, so the lift comes from the field count and layout together.
Who ran it
InsightWhale ran this test for a destination travel company (deal page enquiry form) and published the results (Convert case study). The numbers are theirs; the summary and commentary on this page are ours.
Read the original case study on InsightWhale →
How to run this test on your site
- Hypothesis
- If we show only the required fields and hide optional ones behind a toggle, then more visitors will submit the form because it looks shorter and quicker to finish.
- Primary metric
- Form submission rate on the page
- Guardrails
- Lead quality or enquiry-to-booking rate
- Share of leads with optional fields filled
- Bounce rate
- Who should test it
- Lead-gen businesses with long enquiry or quote forms, especially with heavy mobile traffic. It may not help if your sales team truly needs every field to qualify a lead.
Questions
Does marking form fields optional increase conversions?
Not on its own here. The version that kept all eight fields visible but marked five optional converted about the same as the original.
Hiding the optional fields is what made the difference.
How many fields should a lead form have?
As few as you need to follow up.
Ask for the essentials first and offer the rest as optional, or collect it later in the sales process.
Why use a single-column form?
One column gives a clear top-to-bottom path and works better on phones.
Multi-column layouts can make people skip or miss fields.