Htaccess snippet for forcing trailing slash at the end of urls.

.htaccess

# ------------------------------------------------------------------------------
# | Suppressing / Forcing the "/" at the end of URLs                           |
# ------------------------------------------------------------------------------

# Place this underneath the 'Suppressing / Forcing the "www."'
# section of the h5bp file, or just ensure it occurs before the
# index.php rewrite.

<IfModule mod_rewrite.c>
    RewriteCond %{REQUEST_FILENAME} !-f
    RewriteCond %{REQUEST_FILENAME} !-d
    RewriteCond %{REQUEST_URI} !(.*)/$
    RewriteRule ^(.*)$ $1/ [R=301]
</IfModule>