Force trailing slash on URLs
I found by just adding the code from the following site it will add slashes via a 301 redirect:

RewriteCond %{REQUEST_URI} /+[^\.]+$
RewriteRule ^(.+[^/])$ %{REQUEST_URI}/ [R=301,L]


Now my .htaccess file looks like the following:

&lt;IfModule mod_rewrite.c&gt;
    RewriteEngine On

    # 301 redirect with trailing slash
    RewriteCond %{REQUEST_URI} /+[^\.]+$
    RewriteRule ^(.+[^/])$ %{REQUEST_URI}/ [R=301,L]

    # Send would-be 404 requests to Craft
    RewriteCond %{REQUEST_FILENAME} !-f
    RewriteCond %{REQUEST_FILENAME} !-d
    RewriteCond %{REQUEST_URI} !^/(favicon\.ico|apple-touch-icon.*\.png)$ [NC]
    RewriteRule (.+) index.php?p=$1 [QSA,L]

&lt;/IfModule&gt;


And here is another version/option which seems to work as well:

RewriteCond %{REQUEST_FILENAME} !-d
RewriteCond %{REQUEST_FILENAME} !-f
RewriteRule ^(.*[^/])$ /$1/ [L,R=301]


Here is a third option which seems to work as well:

# Always append a trailing slash
RewriteCond %{REQUEST_FILENAME} !-f
RewriteCond %{REQUEST_FILENAME} !-d
RewriteCond %{REQUEST_URI} !/$
RewriteRule . %{REQUEST_URI}/ [R=301,L]


I'll update once I've researched and settled upon the best option.