diff --git a/addons/api/addon/serializers/auth-method.js b/addons/api/addon/serializers/auth-method.js
index ff3bdc5ed..a8569c14d 100644
--- a/addons/api/addon/serializers/auth-method.js
+++ b/addons/api/addon/serializers/auth-method.js
@@ -15,4 +15,21 @@ export default class AuthMethodSerializer extends ApplicationSerializer {
     );
     return normalized;
   }
+
+  /**
+   * Sets `is_primary` to `false` if it is missing in the response.  The API
+   * omits "zero" values per:
+   * https://developers.google.com/protocol-buffers/docs/proto3#default
+   *
+   * TODO:  generalize this so that all zero values are reified.
+   * @override
+   * @return {object}
+   */
+  normalize() {
+    const normalized = super.normalize(...arguments);
+    if (!normalized.data.attributes.is_primary) {
+      normalized.data.attributes.is_primary = false;
+    }
+    return normalized;
+  }
 }
diff --git a/addons/api/tests/unit/serializers/auth-method-test.js b/addons/api/tests/unit/serializers/auth-method-test.js
index 2e7494762..cd7fcd396 100644
--- a/addons/api/tests/unit/serializers/auth-method-test.js
+++ b/addons/api/tests/unit/serializers/auth-method-test.js
@@ -49,13 +49,13 @@ module('Unit | Serializer | auth method', function (hooks) {
           {
             id: '1',
             type: 'auth-method',
-            attributes: {},
+            attributes: { is_primary: false },
             relationships: {},
           },
           {
             id: '3',
             type: 'auth-method',
-            attributes: {},
+            attributes: { is_primary: false },
             relationships: {},
           },
         ],