Prevent Free-Trial Abuse and Protect Your SaaS

Always require users to confirm their email address during signup. Sending an automated message with a unique link ensures the address is valid and accessible before activating the account. For additional security, you can include a ‘Confirm Email’ button with a CAPTCHA on the verification page, or even introduce SMS verification as a second step. While SMS checks are effective at discouraging abusers, they may also deter some legitimate users who are reluctant to share their phone number. Nonetheless, email verification remains a fundamental safeguard and should always be implemented in any signup process or web form that collects user emails.

Instead of activating a free trial right after signup, request a valid credit card for verification. Even if no charge is made (e.g., a $0 authorization), this step can filter out suspicious accounts and ensures you onboard serious users with real purchase intent. Many SaaS products also let users select a plan, provide their card details, and enjoy the trial period before the subscription begins—charging automatically once the trial ends. However, some users may hesitate to enter card details before trying a product, or may fear accidental charges.

By monitoring IP addresses, you can block new signups once a certain number of accounts (N) have already been created from the same source. This helps detect and stop users attempting to create multiple accounts and abuse free trials. While it’s normal for some IPs to be shared within the same office or company network, a sudden spike of registrations from one IP within a short timeframe is a strong signal of suspicious or fraudulent activity.

Some email providers allow the use of aliases in the email username, such as user+alias@domain.com. This can be exploited to create multiple accounts using what is effectively the same email address, just with different aliases. Gmail also treats dots in the username as non-significant — for example, if you own johnsmith@gmail.com then any email sent to johnsmith@gmail.com, john.smith@gmail.com, or j.o.h.n.smith@gmail.com will all reach the same inbox. To prevent abuse you should remove the +alias and the dots (on a gmail address) before checking for duplicates.

Another option you can consider, is to restrict access to certain features during the free trial period. While this approach may prevent users from experiencing the product in its entirety, it helps strike a balance between offering a meaningful evaluation and controlling potential misuse or costs. Examples include adding watermarks to downloadable content, limiting access to resource-intensive features, or capping the number of times an action can be performed.

Depending on your SaaS target audience, you may want to block free email domains such as Gmail, Hotmail, or Yahoo, as well as email forwarding services like SimpleLogin or ProxiedMail. Since business users are far less likely to abuse free trials, restricting free emails can reduce fraudulent signups and protect freemium plans. If your product is aimed at companies rather than individuals, blocking free emails at signup can be an effective safeguard against abuse.

Instead of granting free trials automatically after signup, make them available on request. Add a ‘Request Free Trial’ button and ask users to briefly describe their intended use case. This approach helps you engage directly with potential customers, learn more about their company, and assess their legitimacy before enabling access. While it may introduce some manual work, it often results in higher-quality leads, stronger conversion rates, and a reduced risk of trial abuse. If you want to automate the process, you can grant the free trial a few minutes after the request to avoid delays, and eventually manually review it later or mark it as "to review" if the use case text is too short, for example.

Free trials are a great way to let potential customers experience your product, but they can also invite abuse and unnecessary costs (that can be potentially high in some cases). One alternative may be to remove the free trial entirely and instead offer a clear ‘30-Day Money Back’ guarantee. You can also showcase the product through demo videos, guided walkthroughs, or real use cases from paying customers. By highlighting the value of the paid version upfront, you reduce trial abuse while still giving prospects the confidence they need to purchase.