How to give userA sharepoint group "Readers permission" on the site and "Contributor permission" on ListA?

Question

I am using SharePoint 2013. I would like to give userA the whole site read permission. I add userA to the usergroup "Readers".

I have many lists in my site. I would like to give userA contributor permissions only to ListA. How can I do this?

Answer 1

You need to break permission inheritance on the specific list, and then add userA with contributor permissions on the list level.

1. Open the list that you want to restrict access to.
2. On the List Tools tab, click List to open the gallery of commands specific to the list.

3. On the ribbon, click the List Permissions button.

4. The permissions page for the list opens, with a yellow status bar that explains that the list inherits permission from its parent site.

5. Click the Stop Inheriting Permissions button.

and then

1. On the permissions page for the list [step 1-4 above], on the Edit tab, click the Grant Permissions button.
2. Type the name of the group or the individual you want to grant access to in the Users/Groups box.
3. Choose the level of permissions you want the group or individuals to have.
4. Click OK.

Source and more information here