# Removing mailing-list checkboxes from sign-up: no change in trials

- Outcome: Flat / inconclusive
- Page type: Signup page (SaaS)
- Elements: Form fields
- Date shared: 2009-08
- Test run by: [Patrick McKenzie](https://liftarchive.com/practitioners/patrick-mckenzie/)
- Commentary by: LiftArchive (our analysis, not theirs)
- Original source: https://www.kalzumeus.com/2009/08/19/minor-lessons-from-ab-testing/
- Page: https://liftarchive.com/test/patio11-bcc-email-permission-checkboxes/

Removing two mailing-list opt-in checkboxes from the sign-up form made no significant difference to trial sign-ups. Patrick McKenzie ran this split test on the web version of Bingo Card Creator and shared it on the Kalzumeus (patio11) blog. The author called the test flawed, because a no-spam note was removed along with the checkboxes.

## Result

**no change in trials**

- Trial sign-ups: no significant difference. Flat.
- No sign-up numbers, sample size or test length were shared.
- Because two things changed at once, the result can't tell you the effect of the checkboxes alone.

## Control

The registration form asked for an email address and showed two checkboxes for joining the mailing list, with a note promising no spam.

## Variant

The same form with both checkboxes and the no-spam note removed. The email address was still required, as it served as the username.

## Why it likely came out this way (our reading)

- Two optional checkboxes add little effort, so removing them didn't make the form noticeably easier.
- The email field stayed, so the main privacy concern for visitors didn't change.
- Losing the no-spam reassurance may have cancelled out any small gain from a shorter form.

## Caveats

No numbers, sample size or duration were shared. The author said the test was flawed because the no-spam wording should have stayed in both versions.

## How to run this test

- Hypothesis: If we remove optional mailing-list checkboxes from our sign-up form but keep a no-spam note, then sign-ups will rise because the form looks shorter while still reassuring people.
- Primary metric: Trial sign-ups per sign-up page visitor
- Guardrail: Mailing list opt-in rate
- Guardrail: Email unsubscribe rate
- Guardrail: Trial-to-paid rate
- Who should test it: SaaS and lead-gen businesses with extra opt-in options on the sign-up form. Change only the checkboxes, and skip it if your mailing list drives a large share of paid conversions.

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Credit: Patrick McKenzie ran this test and owns the result. Summary and commentary by LiftArchive (https://liftarchive.com/test/patio11-bcc-email-permission-checkboxes/).
Usage: Free to use, quote and build on, with credit and a link: name the practitioner or organization that ran the test and link to its LiftArchive page. The results belong to the practitioners who ran and shared them; the summaries and commentary are LiftArchive's.