Within the portal you have the ability to close a survey when you are finished gathering data from respondents. First, locate your project in the portal and click on the name of the project. A drop-down menu will appear with a list of options. Under the "Distribute" header, select "Close Survey".
A new window will open asking if you are sure you want to close your survey. If you are not sure, click "Cancel", otherwise click "Close Survey".
Your survey will automatically close and the new project status will read "Closed". Respondents trying to enter the survey will now be shown a message alerting them it is closed.