Is there a way to turn off a survey after a set number of entries?

We are looking to launch a registration form for a retreat that has a set number of spots. Is there a way for the form to automatically close after we hit our limit? 

Yes, there are a number of ways on how you can automatically disable your form depending on the number of submissions it already received. You can find the feature on this guide: https://www.jotform.com/help/137-How-to-limit-submissions-in-a-form 

You can disable by date and/or number of submissions using that feature.

I hope that helps.