diff --git a/test/intl402/NumberFormat/test-option-useGrouping-extended.js b/test/intl402/NumberFormat/test-option-useGrouping-extended.js
index 94d74777a1..2cec7fb601 100644
--- a/test/intl402/NumberFormat/test-option-useGrouping-extended.js
+++ b/test/intl402/NumberFormat/test-option-useGrouping-extended.js
@@ -35,6 +35,5 @@ assert.sameValue(render({notation: 'compact', useGrouping: false}), false, 'comp
 assert.sameValue(render({notation: 'compact', useGrouping: null}), false, 'compact, null');
 assert.sameValue(render({notation: 'compact', useGrouping: 'min2'}), 'min2', 'compact, "min2"');
 
-assert.sameValue(render({useGrouping: 'undefined'}), 'auto', 'use fallback value');
 assert.sameValue(render({useGrouping: 'false'}), 'auto', 'use fallback value');
 assert.sameValue(render({useGrouping: 'true'}), 'auto', 'use fallback value');
diff --git a/test/intl402/NumberFormat/test-option-useGrouping.js b/test/intl402/NumberFormat/test-option-useGrouping.js
index ba3e0895ce..e9565bf852 100644
--- a/test/intl402/NumberFormat/test-option-useGrouping.js
+++ b/test/intl402/NumberFormat/test-option-useGrouping.js
@@ -31,7 +31,7 @@ for (let falsy of [0, null, ""]) {
   assert.sameValue(resolveUseGrouping(falsy), false);
 }
 
-for (let invalidOptions of [42, "MIN2", {} , "True",  "TRUE" , "FALSE" , "False"]) {
+for (let invalidOptions of [42, "MIN2", {} , "True",  "TRUE" , "FALSE" , "False" , "Undefined" , "undefined"]) {
   assert.throws(RangeError, function () {
     return new Intl.NumberFormat(undefined, { useGrouping: invalidOptions });
   }, "Throws RangeError when useGrouping value is not supported");