smatric

This is a very small plugin that forces users to login before viewing any content. This is done by checking if the user is logged in, and if not, redirecting them to the login page. Users attempting to view blog content via RSS are also authenticated via HTTP Auth.
Modification: use get_site_url() to redirect to the login page properly when WordPress is located in a subdirectory.

Force User Login

A very small plugin that forces users to login to view blog content.

Silver Muru

WS Force Login Page force users who are not logged in by redirect into login page, this way it is good tool for developers to install sites which are in development process by restrict access to site and its content. Or when you want to put all site articles under password this plugin will do this! Working also with domains what includes umlaut letters like ö, ä, õ, ü
Suitable also for putting site to maintenance mode and show custom message in login view.

WS Force Login Page

I had problem with other similar plugins what didnt work in sites with domains what included umlaut letters like ö, ä, õ, ü thats why I needed this kind of plugin



Useful

Redirecting user to login page if not logged in, working also with domains what includes umlaut letters like ö, ä, õ, ü

Force User Login vs WS Force Login Page