diff --git a/test/built-ins/Temporal/PlainDateTime/prototype/weekOfYear/basic.js b/test/built-ins/Temporal/PlainDateTime/prototype/weekOfYear/basic.js
index 4d8c71fd684..b2fd5518679 100644
--- a/test/built-ins/Temporal/PlainDateTime/prototype/weekOfYear/basic.js
+++ b/test/built-ins/Temporal/PlainDateTime/prototype/weekOfYear/basic.js
@@ -3,9 +3,35 @@
 
 /*---
 esid: sec-get-temporal.plaindatetime.prototype.weekofyear
-description: Checking week of year for a "normal" case (non-undefined, non-boundary case, etc.)
+description: Checking week of year for a "normal" case, as well as for dates near the turn of the year.
 features: [Temporal]
 ---*/
 
-const datetime = new Temporal.PlainDateTime(1976, 11, 18, 15, 23, 30, 123, 456, 789, "iso8601");
+const datetime = new Temporal.PlainDateTime(1976, 11, 18, 15, 23, 30, 123, 456, 789);
 assert.sameValue(datetime.weekOfYear, 47, "check week of year information");
+
+for (let i = 29; i <= 31; ++i) {
+  const datetime = new Temporal.PlainDateTime(1975, 12, i, 15, 23, 30, 123, 456, 789);
+  assert.sameValue(datetime.weekOfYear, 1, `${datetime} should be in week 1`);
+}
+for (let i = 1; i <= 4; ++i) {
+  const datetime = new Temporal.PlainDateTime(1976, 1, i, 15, 23, 30, 123, 456, 789);
+  assert.sameValue(datetime.weekOfYear, 1, `${datetime} should be in week 1`);
+}
+for (let i = 5; i <= 11; ++i) {
+  const datetime = new Temporal.PlainDateTime(1976, 1, i, 15, 23, 30, 123, 456, 789);
+  assert.sameValue(datetime.weekOfYear, 2, `${datetime} should be in week 2`);
+}
+for (let i = 20; i <= 26; ++i) {
+  const datetime = new Temporal.PlainDateTime(1976, 12, i, 15, 23, 30, 123, 456, 789);
+  assert.sameValue(datetime.weekOfYear, 52, `${datetime} should be in week 52`);
+}
+for (let i = 27; i <= 31; ++i) {
+  const datetime = new Temporal.PlainDateTime(1976, 12, i, 15, 23, 30, 123, 456, 789);
+  assert.sameValue(datetime.weekOfYear, 53, `${datetime} should be in week 53`);
+}
+for (let i = 1; i <= 2; ++i) {
+  const datetime = new Temporal.PlainDateTime(1977, 1, i, 15, 23, 30, 123, 456, 789);
+  assert.sameValue(datetime.weekOfYear, 53, `${datetime} should be in week 53`);
+}
+
diff --git a/test/built-ins/Temporal/ZonedDateTime/prototype/weekOfYear/basic.js b/test/built-ins/Temporal/ZonedDateTime/prototype/weekOfYear/basic.js
new file mode 100644
index 00000000000..d199da9def9
--- /dev/null
+++ b/test/built-ins/Temporal/ZonedDateTime/prototype/weekOfYear/basic.js
@@ -0,0 +1,37 @@
+// Copyright (C) 2026 Igalia, S.L. All rights reserved.
+// This code is governed by the BSD license found in the LICENSE file.
+
+/*---
+esid: sec-get-temporal.zoneddatetime.prototype.weekofyear
+description: Checking week of year for a "normal" case, as well as for dates near the turn of the year.
+features: [Temporal]
+---*/
+
+const zdt = new Temporal.PlainDateTime(1976, 11, 18, 15, 23, 30, 123, 456, 789).toZonedDateTime("UTC");
+assert.sameValue(zdt.weekOfYear, 47, "check week of year information");
+
+for (let i = 29; i <= 31; ++i) {
+  const zdt = new Temporal.PlainDateTime(1975, 12, i, 15, 23, 30, 123, 456, 789).toZonedDateTime("UTC");
+  assert.sameValue(zdt.weekOfYear, 1, `${zdt} should be in week 1`);
+}
+for (let i = 1; i <= 4; ++i) {
+  const zdt = new Temporal.PlainDateTime(1976, 1, i, 15, 23, 30, 123, 456, 789).toZonedDateTime("UTC");
+  assert.sameValue(zdt.weekOfYear, 1, `${zdt} should be in week 1`);
+}
+for (let i = 5; i <= 11; ++i) {
+  const zdt = new Temporal.PlainDateTime(1976, 1, i, 15, 23, 30, 123, 456, 789).toZonedDateTime("UTC");
+  assert.sameValue(zdt.weekOfYear, 2, `${zdt} should be in week 2`);
+}
+for (let i = 20; i <= 26; ++i) {
+  const zdt = new Temporal.PlainDateTime(1976, 12, i, 15, 23, 30, 123, 456, 789).toZonedDateTime("UTC");
+  assert.sameValue(zdt.weekOfYear, 52, `${zdt} should be in week 52`);
+}
+for (let i = 27; i <= 31; ++i) {
+  const zdt = new Temporal.PlainDateTime(1976, 12, i, 15, 23, 30, 123, 456, 789).toZonedDateTime("UTC");
+  assert.sameValue(zdt.weekOfYear, 53, `${zdt} should be in week 53`);
+}
+for (let i = 1; i <= 2; ++i) {
+  const zdt = new Temporal.PlainDateTime(1977, 1, i, 15, 23, 30, 123, 456, 789).toZonedDateTime("UTC");
+  assert.sameValue(zdt.weekOfYear, 53, `${zdt} should be in week 53`);
+}
+
diff --git a/test/staging/Temporal/v8/calendar-week-of-year.js b/test/staging/Temporal/v8/calendar-week-of-year.js
deleted file mode 100644
index 4aeab8a7cba..00000000000
--- a/test/staging/Temporal/v8/calendar-week-of-year.js
+++ /dev/null
@@ -1,49 +0,0 @@
-// Copyright 2021 the V8 project authors. All rights reserved.
-// This code is governed by the BSD license found in the LICENSE file.
-
-/*---
-esid: pending
-description: >
-  Automatically ported from calendar-week-of-year test
-  in V8's mjsunit test calendar-week-of-year.js
-features: [Temporal]
----*/
-
-assert.sameValue((new Temporal.PlainDate(1977, 1, 1)).weekOfYear, 53);
-assert.sameValue((new Temporal.PlainDate(1977, 1, 2)).weekOfYear, 53);
-assert.sameValue((new Temporal.PlainDate(1977, 12, 31)).weekOfYear, 52);
-assert.sameValue((new Temporal.PlainDate(1978, 1, 1)).weekOfYear, 52);
-assert.sameValue((new Temporal.PlainDate(1978, 1, 2)).weekOfYear, 1);
-assert.sameValue((new Temporal.PlainDate(1978, 12, 31)).weekOfYear, 52);
-assert.sameValue((new Temporal.PlainDate(1979, 1, 1)).weekOfYear, 1);
-assert.sameValue((new Temporal.PlainDate(1979, 12, 30)).weekOfYear, 52);
-assert.sameValue((new Temporal.PlainDate(1979, 12, 31)).weekOfYear, 1);
-assert.sameValue((new Temporal.PlainDate(1980, 1, 1)).weekOfYear, 1);
-assert.sameValue((new Temporal.PlainDate(1980, 12, 28)).weekOfYear, 52);
-assert.sameValue((new Temporal.PlainDate(1980, 12, 29)).weekOfYear, 1);
-assert.sameValue((new Temporal.PlainDate(1980, 12, 30)).weekOfYear, 1);
-assert.sameValue((new Temporal.PlainDate(1980, 12, 31)).weekOfYear, 1);
-assert.sameValue((new Temporal.PlainDate(1981, 1, 1)).weekOfYear, 1);
-assert.sameValue((new Temporal.PlainDate(1981, 12, 31)).weekOfYear, 53);
-assert.sameValue((new Temporal.PlainDate(1982, 1, 1)).weekOfYear, 53);
-assert.sameValue((new Temporal.PlainDate(1982, 1, 2)).weekOfYear, 53);
-assert.sameValue((new Temporal.PlainDate(1982, 1, 3)).weekOfYear, 53);
-assert.sameValue(Temporal.PlainDate.from('1977-01-01').weekOfYear, 53);
-assert.sameValue(Temporal.PlainDate.from('1977-01-02').weekOfYear, 53);
-assert.sameValue(Temporal.PlainDate.from('1977-12-31').weekOfYear, 52);
-assert.sameValue(Temporal.PlainDate.from('1978-01-01').weekOfYear, 52);
-assert.sameValue(Temporal.PlainDate.from('1978-01-02').weekOfYear, 1);
-assert.sameValue(Temporal.PlainDate.from('1978-12-31').weekOfYear, 52);
-assert.sameValue(Temporal.PlainDate.from('1979-01-01').weekOfYear, 1);
-assert.sameValue(Temporal.PlainDate.from('1979-12-30').weekOfYear, 52);
-assert.sameValue(Temporal.PlainDate.from('1979-12-31').weekOfYear, 1);
-assert.sameValue(Temporal.PlainDate.from('1980-01-01').weekOfYear, 1);
-assert.sameValue(Temporal.PlainDate.from('1980-12-28').weekOfYear, 52);
-assert.sameValue(Temporal.PlainDate.from('1980-12-29').weekOfYear, 1);
-assert.sameValue(Temporal.PlainDate.from('1980-12-30').weekOfYear, 1);
-assert.sameValue(Temporal.PlainDate.from('1980-12-31').weekOfYear, 1);
-assert.sameValue(Temporal.PlainDate.from('1981-01-01').weekOfYear, 1);
-assert.sameValue(Temporal.PlainDate.from('1981-12-31').weekOfYear, 53);
-assert.sameValue(Temporal.PlainDate.from('1982-01-01').weekOfYear, 53);
-assert.sameValue(Temporal.PlainDate.from('1982-01-02').weekOfYear, 53);
-assert.sameValue(Temporal.PlainDate.from('1982-01-03').weekOfYear, 53);