There is no cost for basic access to the BYU corpora. But you will occasionally see this message, which asks you to consider upgrading to a "premium" account.
If you have a premium account ($8.00 per month or $25.00 per year), then you will not see this message anymore. You will also have increased access to the corpora, more features, and you will help to support the BYU corpora.
If you are a student, your school or university can also get an academic license, and all of you will have the benefits of a premium account.
Thanks for your support.