As many as you have good, quality mentors to lead. Don’t focus on the number of groups you want to launch, think about it in terms of how many quality mentors you have. If the mentor isn’t ready and able, the group won’t reach its potential.
It’s better to start small and grow, so our recommendation for most churches is to start with one or two groups. Some churches launch with more groups and it works out great, but if there is any uncertainty, start with one and grow from there. The first year will always be the hardest because it’s new. After that, you’ll have stories of life change and word-of-mouth excitement to help you evaluate and grow.