The answer is no. In order to upgrade your Nikabot account and continue using the Nikabot service after the free trial, you do not have to have a paid account Slack account. 

You may use Nikabot with a free Slack account - in that case, Slack will only display the most recent 10,000 messages and archive anything older than that, but that has no impact on using Nikabot.

Did this answer your question?