I've always stored my fonts inside the ~/.fonts directory.

I've decided to move all of them to /usr/local/share/fonts/ after reading /usr/local/etc/fonts/fonts.conf file.

<!-- Font directory list -->

        <dir>/usr/local/share/fonts</dir>

        <dir prefix="xdg">fonts</dir>
        <!-- the following element will be removed in the future -->
        <dir>~/.fonts</dir>

Based on the comment "the following element will be removed in the future" I think it's safe to assume that ~/.fonts might stop working at some point.

Remember to run fc-cache(1) to scan the font directories and build cache files. I usually run it with -f flag to force re-generation.