diff --git a/test/built-ins/Temporal/PlainYearMonth/prototype/add/options-read-before-algorithmic-validation.js b/test/built-ins/Temporal/PlainYearMonth/prototype/add/options-read-before-algorithmic-validation.js
index 3f9bb7bbd37..e93e660308c 100644
--- a/test/built-ins/Temporal/PlainYearMonth/prototype/add/options-read-before-algorithmic-validation.js
+++ b/test/built-ins/Temporal/PlainYearMonth/prototype/add/options-read-before-algorithmic-validation.js
@@ -26,3 +26,12 @@ assert.throws(RangeError, function () {
   instance.add(new Temporal.Duration(0, 1), options);
 }, "exception thrown when converting -271821-04 to date");
 assert.compareArray(actual, expected, "all options should be read first");
+
+actual.splice(0);  // clear
+
+const instance2 = new Temporal.PlainYearMonth(1999, 12);
+
+assert.throws(RangeError, function () {
+  instance2.add(new Temporal.Duration(0, 0, 1), options);
+}, "exception thrown when attempting to add too-low unit");
+assert.compareArray(actual, expected, "all options should be read first");
diff --git a/test/built-ins/Temporal/PlainYearMonth/prototype/subtract/options-read-before-algorithmic-validation.js b/test/built-ins/Temporal/PlainYearMonth/prototype/subtract/options-read-before-algorithmic-validation.js
index 96873b0eb10..ee5d9c6e5f3 100644
--- a/test/built-ins/Temporal/PlainYearMonth/prototype/subtract/options-read-before-algorithmic-validation.js
+++ b/test/built-ins/Temporal/PlainYearMonth/prototype/subtract/options-read-before-algorithmic-validation.js
@@ -26,3 +26,12 @@ assert.throws(RangeError, function () {
   instance.subtract(new Temporal.Duration(0, -1), options);
 }, "exception thrown when converting -271821-04 to date");
 assert.compareArray(actual, expected, "all options should be read first");
+
+actual.splice(0);  // clear
+
+const instance2 = new Temporal.PlainYearMonth(1999, 12);
+
+assert.throws(RangeError, function () {
+  instance2.add(new Temporal.Duration(0, 0, 1), options);
+}, "exception thrown when attempting to add too-low unit");
+assert.compareArray(actual, expected, "all options should be read first");