<% f.fields_for :order do |order_form| %> <% order_form.fields_for :checkout do |checkout_form| %> <% checkout_form.fields_for :bill_address do |ba_form| %> <%= render :partial => "admin/shared/address_form", :locals => {:f => ba_form, :name => t('billing_address')} %> <% end %> <% end %> <% end %>