diff --git a/netbox/dcim/forms.py b/netbox/dcim/forms.py
index 257907015..83cdff29e 100644
--- a/netbox/dcim/forms.py
+++ b/netbox/dcim/forms.py
@@ -1833,7 +1833,10 @@ class CableCreateForm(BootstrapMixin, ChainedFieldsMixin, forms.ModelForm):
         label='Name',
         widget=APISelect(
             api_url='/api/dcim/{{termination_b_type}}s/?device_id={{termination_b_device}}',
-            disabled_indicator='cable'
+            disabled_indicator='cable',
+            url_conditional_append={
+                'termination_b_type__interface': '&type=physical',
+            }
         )
     )
 
diff --git a/netbox/project-static/js/forms.js b/netbox/project-static/js/forms.js
index 7ea4b152b..a494664c7 100644
--- a/netbox/project-static/js/forms.js
+++ b/netbox/project-static/js/forms.js
@@ -91,8 +91,9 @@ $(document).ready(function() {
                 var filter_regex = /\{\{([a-z_]+)\}\}/g;
                 var match;
                 var rendered_url = api_url;
+                var filter_field;
                 while (match = filter_regex.exec(api_url)) {
-                    var filter_field = $('#id_' + match[1]);
+                    filter_field = $('#id_' + match[1]);
                     var custom_attr = $('option:selected', filter_field).attr('api-value');
                     if (custom_attr) {
                         rendered_url = rendered_url.replace(match[0], custom_attr);
@@ -103,6 +104,20 @@ $(document).ready(function() {
                     }
                 }
 
+                // Account for any conditional URL append strings
+                $.each(child_field[0].attributes, function(index, attr){
+                    if (attr.name.includes("data-url-conditional-append-")){
+                        var conditional = attr.name.split("data-url-conditional-append-")[1].split("__");
+                        var field = $("#id_" + conditional[0]);
+                        var field_value = conditional[1];
+                        console.log($('option:selected', field).attr('api-value'));
+                        if ($('option:selected', field).attr('api-value') === field_value){
+                            console.log(attr.value);
+                            rendered_url = rendered_url + attr.value;
+                        }
+                    }
+                })
+
                 // If all URL variables have been replaced, make the API call
                 if (rendered_url.search('{{') < 0) {
                     console.log(child_name + ": Fetching " + rendered_url);
diff --git a/netbox/utilities/forms.py b/netbox/utilities/forms.py
index baa035aa7..51e553cf9 100644
--- a/netbox/utilities/forms.py
+++ b/netbox/utilities/forms.py
@@ -258,9 +258,21 @@ class APISelect(SelectWithDisabled):
     :param api_url: API URL
     :param display_field: (Optional) Field to display for child in selection list. Defaults to `name`.
     :param disabled_indicator: (Optional) Mark option as disabled if this field equates true.
+    :param url_conditional_append: (Optional) A dict of URL query strings to append to the URL if the
+        condition is met. The condition is the dict key and is specified in the form `<field_name>__<field_value>`.
+        If the provided field value is selected for the given field, the URL query string will be appended to
+        the rendered URL. This is useful in cases where a particular field value dictates an additional API filter.
     """
 
-    def __init__(self, api_url, display_field=None, disabled_indicator=None, *args, **kwargs):
+    def __init__(
+        self,
+        api_url,
+        display_field=None,
+        disabled_indicator=None,
+        url_conditional_append=None,
+        *args,
+        **kwargs
+    ):
 
         super(APISelect, self).__init__(*args, **kwargs)
 
@@ -270,6 +282,9 @@ class APISelect(SelectWithDisabled):
             self.attrs['display-field'] = display_field
         if disabled_indicator:
             self.attrs['disabled-indicator'] = disabled_indicator
+        if url_conditional_append:
+            for key, value in url_conditional_append.items():
+                self.attrs["data-url-conditional-append-{}".format(key)] = value
 
 
 class APISelectMultiple(APISelect):