diff --git a/polyfill/lib/plainmonthday.mjs b/polyfill/lib/plainmonthday.mjs
index e24031458a..a1089f289c 100644
--- a/polyfill/lib/plainmonthday.mjs
+++ b/polyfill/lib/plainmonthday.mjs
@@ -91,7 +91,7 @@ export class PlainMonthDay {
     const concatenatedFieldNames = ES.Call(ArrayPrototypeConcat, receiverFieldNames, inputFieldNames);
     mergedFields = ES.PrepareTemporalFields(mergedFields, concatenatedFieldNames, [], [], 'ignore');
     const options = ObjectCreate(null);
-    options.overflow = 'reject';
+    options.overflow = 'constrain';
     return ES.CalendarDateFromFields(calendarRec, mergedFields, options);
   }
   getISOFields() {
diff --git a/polyfill/lib/plainyearmonth.mjs b/polyfill/lib/plainyearmonth.mjs
index 6d80552fe7..98e48c74a4 100644
--- a/polyfill/lib/plainyearmonth.mjs
+++ b/polyfill/lib/plainyearmonth.mjs
@@ -132,7 +132,7 @@ export class PlainYearMonth {
     const concatenatedFieldNames = ES.Call(ArrayPrototypeConcat, receiverFieldNames, inputFieldNames);
     mergedFields = ES.PrepareTemporalFields(mergedFields, concatenatedFieldNames, [], [], 'ignore');
     const options = ObjectCreate(null);
-    options.overflow = 'reject';
+    options.overflow = 'constrain';
     return ES.CalendarDateFromFields(calendarRec, mergedFields, options);
   }
   getISOFields() {
diff --git a/polyfill/test262 b/polyfill/test262
index 27a7501893..6cbb6da947 160000
--- a/polyfill/test262
+++ b/polyfill/test262
@@ -1 +1 @@
-Subproject commit 27a7501893a46993194bf6e82d62e2a139041aea
+Subproject commit 6cbb6da9473c56d95358d8e679c5a6d2b4574efb
diff --git a/spec/plainmonthday.html b/spec/plainmonthday.html
index ae355e7246..d5f57b503d 100644
--- a/spec/plainmonthday.html
+++ b/spec/plainmonthday.html
@@ -250,7 +250,7 @@ <h1>Temporal.PlainMonthDay.prototype.toPlainDate ( _item_ )</h1>
         1. Let _concatenatedFieldNames_ be the list-concatenation of _receiverFieldNames_ and _inputFieldNames_.
         1. Set _mergedFields_ to ? PrepareTemporalFields(_mergedFields_, _concatenatedFieldNames_, «», «», ~ignore~).
         1. Let _options_ be OrdinaryObjectCreate(*null*).
-        1. Perform ! CreateDataPropertyOrThrow(_options_, *"overflow"*, *"reject"*).
+        1. Perform ! CreateDataPropertyOrThrow(_options_, *"overflow"*, *"constrain"*).
         1. Return ? CalendarDateFromFields(_calendarRec_, _mergedFields_, _options_).
       </emu-alg>
     </emu-clause>
diff --git a/spec/plainyearmonth.html b/spec/plainyearmonth.html
index 8d11d3609a..0fe491e23d 100644
--- a/spec/plainyearmonth.html
+++ b/spec/plainyearmonth.html
@@ -380,7 +380,7 @@ <h1>Temporal.PlainYearMonth.prototype.toPlainDate ( _item_ )</h1>
         1. Let _concatenatedFieldNames_ be the list-concatenation of _receiverFieldNames_ and _inputFieldNames_.
         1. Set _mergedFields_ to ? PrepareTemporalFields(_mergedFields_, _concatenatedFieldNames_, «», «», ~ignore~).
         1. Let _options_ be OrdinaryObjectCreate(*null*).
-        1. Perform ! CreateDataPropertyOrThrow(_options_, *"overflow"*, *"reject"*).
+        1. Perform ! CreateDataPropertyOrThrow(_options_, *"overflow"*, *"constrain"*).
         1. Return ? CalendarDateFromFields(_calendarRec_, _mergedFields_, _options_).
       </emu-alg>
     </emu-clause>