A free trial lets a prospect use a paid product, usually with most or all features, for a limited time before deciding whether to buy. Trials can be opt-in, where no payment details are needed and the account stops at the end, or opt-out, where a card is collected and billing starts automatically unless the user cancels. The choice affects both conversion numbers and legal obligations.
Opt-in and opt-out trials
Opt-in trials, without a card, attract more sign-ups because the barrier is lower, but a smaller share convert to paid. Opt-out trials, with a card required, attract fewer sign-ups, and more of those that start become paying, partly because some users forget to cancel. That second effect can raise churn and refund requests later.
Legal considerations
Trials that convert automatically into paid subscriptions fall under consumer protection and automatic renewal rules in many jurisdictions. These typically require clear disclosure of the price and renewal terms before sign-up, affirmative consent, and an easy way to cancel. In the United States, the FTC's 2024 negative option rule was vacated by a federal appeals court in 2025, but existing federal law and many state automatic renewal laws still apply. Rules differ by country and change, so check current requirements with a lawyer for each market you sell in.
Designing a trial that converts
Trial length is often chosen by habit. Look at when converting users actually reach value and set the length from that.
- Pick a length that fits the time to value. A trial shorter than the time needed to see results loses buyers.
- Guide users to the activation event early in the trial.
- Show what happens at the end of the trial clearly, before it ends.
- For sales-assisted products, offer help to trial accounts that match the ideal customer profile.
Trials and search traffic
Searchers with high commercial intent, such as those on comparison or pricing pages, are good candidates for a trial call to action. Searchers reading early educational content may not be ready to start a clock. Offering a lower-commitment next step on those pages, such as a template or newsletter, can suit them better.
Example
Matching trial length to setup time
Hypothetical company Ferncastle sells a payroll tool with a 7-day trial. Its data shows most converting accounts needed close to two weeks to run a first test payroll. It extends the trial to 21 days and adds a guided first payroll checklist, then tracks whether conversion changes.
Common mistakes
Hiding the renewal terms
Unclear auto-renewal terms create chargebacks, complaints and legal risk. State the price and date plainly.
Questions
Long enough for a typical user to reach the product's value, and no longer than needed. Base it on your own time-to-value data rather than a convention.
