Limit countries shown in checkout shipping to countries assigned in shipping zones settings? Is there a way to restrict the list of countries available in the checkout shipping address select menu to the countries assigned in the shipping zones?
You would need to either 

1) Delete all the countries you don't use within your site in commerce &gt; settings &gt; countries.

2) Simply hide them in twig with something like this:

{% set allowedCountryIds = [1,3,4,6,7] %}
{% for key, country in craft.commerce.countriesList %}
  {% if key in allowedCountryIds %}
    &lt;option value="{{ key }}"&gt;{{ option }}&lt;/option&gt;
  {% endif %}
{% endfor %}