Does a service dropdown with a default lift mobile conversion?

Our mobile homepage form asked visitors to pick a service from a list of radio buttons. We tested a dropdown set to the most popular service. Over 15 days, conversion fell 8.8%, short of our confidence bar.

Not significant Mobile 15 days Not called

SURFACE

Homepage

DEVICE

Mobile

VERTICAL

Ecommerce (B2C)

PRIMARY METRIC

Conversion rate

VARIATIONS

1

The hypothesis

By replacing the service radio buttons with a dropdown set to the most popular service, we will reduce effort on the mobile form, resulting in more visitors reaching checkout.

The form opened with a list of service options that took up space and asked for a choice before visitors could move on. Most visitors picked the same service, so a default looked like a way to save them a step on a small screen.

What we changed

Service radio buttons replaced with a dropdown set to a default

Var A swapped the list of radio buttons for a single dropdown, preselected to the most popular service, and adjusted the spacing around the form. The rest of the page stayed the same.

VAR A: SERVICE DROPDOWN

Radio buttons replaced with a dropdown
Most popular service selected by default
Spacing adjusted around the form

The result

Conversion fell 8.8% with the dropdown, short of our confidence bar

CONVERSION RATE

-8.8%

Over 15 days, the dropdown version converted 8.8% worse than the original. The dropdown trended up over the course of the test, but it never caught the original. The gap did not reach our confidence bar, so we paused the test and kept the radio buttons.

What we would do next

Keep every service in view on the mobile form

Hiding the other services inside a dropdown may have put off visitors who came for something other than a standard renewal. A next test would keep all the options in view and cut effort elsewhere on the form.