In the PublicInput.com system, you can set questions to automatically stop receiving input at a specific date.
To set an end date for all questions, navigate to the project admin page by clicking the 'Admin' link at the bottom of the project website, or from the main admin home page.
From the main tab, head to the 'Survey Questions and Dynamic Content' section:
Click "Edit all". You'll see a modal with options similar to this:
From this dialog, you can stop receiving responses by clicking "Close all now", or input a future date to stop receiving responses.
Please note all future close dates are currently stored and implemented in US Eastern time.
You can verify the time has been set by clicking the settings on any question: