diff --git a/test/built-ins/Temporal/Duration/prototype/round/rounding-window.js b/test/built-ins/Temporal/Duration/prototype/round/rounding-window.js
new file mode 100644
index 0000000000..71c8065f56
--- /dev/null
+++ b/test/built-ins/Temporal/Duration/prototype/round/rounding-window.js
@@ -0,0 +1,29 @@
+// Copyright (C) 2025 Igalia, S.L. All rights reserved.
+// This code is governed by the BSD license found in the LICENSE file.
+
+/*---
+esid: sec-temporal.duration.prototype.round
+description: See https://github.com/tc39/proposal-temporal/issues/3168
+includes: [temporalHelpers.js]
+features: [Temporal]
+---*/
+
+var d = new Temporal.Duration(1, 0, 0, 0, 1);
+var relativeTo = new Temporal.PlainDate(2020, 2, 29);
+TemporalHelpers.assertDuration(d.round({ smallestUnit: 'years', relativeTo }),
+  1, 0, 0, 0, 0, 0, 0, 0, 0, 0);
+
+d = new Temporal.Duration(0, 1, 0, 0, 10);
+relativeTo = new Temporal.PlainDate(2020, 1, 31);
+TemporalHelpers.assertDuration(d.round({ smallestUnit: 'months', roundingMode: 'expand', relativeTo }),
+  0, 2, 0, 0, 0, 0, 0, 0, 0, 0);
+
+d = new Temporal.Duration(2345, 0, 0, 0, 12);
+relativeTo = new Temporal.PlainDate(2020, 2, 29)
+TemporalHelpers.assertDuration(d.round({ smallestUnit: 'years', roundingMode: 'expand', relativeTo }),
+  2346, 0, 0, 0, 0, 0, 0, 0, 0, 0);
+
+d = new Temporal.Duration(1);
+relativeTo = new Temporal.PlainDate(2020, 2, 29)
+TemporalHelpers.assertDuration(d.round({ smallestUnit: 'months', relativeTo }),
+  1, 0, 0, 0, 0, 0, 0, 0, 0, 0);
diff --git a/test/built-ins/Temporal/Duration/prototype/total/rounding-window.js b/test/built-ins/Temporal/Duration/prototype/total/rounding-window.js
new file mode 100644
index 0000000000..4a6e3bbc21
--- /dev/null
+++ b/test/built-ins/Temporal/Duration/prototype/total/rounding-window.js
@@ -0,0 +1,16 @@
+// Copyright (C) 2025 Igalia, S.L. All rights reserved.
+// This code is governed by the BSD license found in the LICENSE file.
+
+/*---
+esid: sec-temporal.duration.prototype.total
+description: See https://github.com/tc39/proposal-temporal/issues/3168
+features: [Temporal]
+---*/
+
+var d = new Temporal.Duration(1, 0, 0, 0, 1);
+var relativeTo = new Temporal.PlainDate(2020, 2, 29);
+assert.sameValue(d.total({ unit: 'years', relativeTo }), 1.0001141552511414);
+
+d = new Temporal.Duration(0, 1, 0, 0, 10);
+relativeTo = new Temporal.PlainDate(2020, 1, 31);
+assert.sameValue(d.total({ unit: 'months', relativeTo }), 1.0134408602150538);