diff --git a/test/built-ins/Temporal/PlainDate/prototype/add/calendar-invalid-return.js b/test/built-ins/Temporal/PlainDate/prototype/add/calendar-invalid-return.js
new file mode 100644
index 0000000000..982c09edf7
--- /dev/null
+++ b/test/built-ins/Temporal/PlainDate/prototype/add/calendar-invalid-return.js
@@ -0,0 +1,36 @@
+// Copyright (C) 2022 Igalia, S.L. All rights reserved.
+// This code is governed by the BSD license found in the LICENSE file.
+
+/*---
+esid: sec-temporal.plaindate.prototype.add
+description: Throw when the returned value from the calendar's dateAdd method is not a PlainDate.
+features: [Temporal]
+---*/
+
+class CustomCalendar extends Temporal.Calendar {
+  constructor(value) {
+    super("iso8601");
+    this.value = value;
+  }
+  dateAdd() {
+    return this.value;
+  }
+}
+
+const tests = [
+  [undefined],
+  [null, "null"],
+  [true],
+  ["2000-05"],
+  [Symbol()],
+  [200005],
+  [200005n],
+  [{}, "plain object"],
+  [() => {}, "lambda"],
+  [Temporal.PlainDate, "Temporal.PlainDate"],
+  [Temporal.PlainDate.prototype, "Temporal.PlainDate.prototype"],
+];
+for (const [test, description = typeof test] of tests) {
+  const plainDate = new Temporal.PlainDate(2000, 5, 2, new CustomCalendar(test));
+  assert.throws(TypeError, () => plainDate.add({ years: 1 }), `Expected error with ${description}`);
+}
diff --git a/test/built-ins/Temporal/PlainDate/prototype/add/custom.js b/test/built-ins/Temporal/PlainDate/prototype/add/custom.js
new file mode 100644
index 0000000000..5e449dc052
--- /dev/null
+++ b/test/built-ins/Temporal/PlainDate/prototype/add/custom.js
@@ -0,0 +1,31 @@
+// Copyright (C) 2022 Igalia, S.L. All rights reserved.
+// This code is governed by the BSD license found in the LICENSE file.
+
+/*---
+esid: sec-temporal.plaindate.prototype.add
+description: Basic tests with custom calendar
+includes: [compareArray.js,temporalHelpers.js]
+features: [Temporal]
+---*/
+
+const result = new Temporal.PlainDate(1920, 5, 3);
+let calls = 0;
+class CustomCalendar extends Temporal.Calendar {
+  constructor() {
+    super("iso8601");
+  }
+  dateAdd(...args) {
+    ++calls;
+    assert.sameValue(args.length, 3, "Three arguments");
+    assert.sameValue(args[0], plainDate, "First argument");
+    TemporalHelpers.assertDuration(args[1], 43, 0, 0, 0, 0, 0, 0, 0, 0, 0, "Second argument");
+    assert.sameValue(typeof args[2], "object", "Third argument: type");
+    assert.sameValue(Object.getPrototypeOf(args[2]), null, "Third argument: prototype");
+    assert.compareArray(Object.keys(args[2]), [], "Third argument: keys");
+    return result;
+  }
+}
+const calendar = new CustomCalendar();
+const plainDate = new Temporal.PlainDate(1976, 11, 18, calendar);
+assert.sameValue(plainDate.add({ years: 43 }), result);
+assert.sameValue(calls, 1);
diff --git a/test/built-ins/Temporal/PlainDate/prototype/subtract/calendar-invalid-return.js b/test/built-ins/Temporal/PlainDate/prototype/subtract/calendar-invalid-return.js
new file mode 100644
index 0000000000..574040aaa0
--- /dev/null
+++ b/test/built-ins/Temporal/PlainDate/prototype/subtract/calendar-invalid-return.js
@@ -0,0 +1,36 @@
+// Copyright (C) 2022 Igalia, S.L. All rights reserved.
+// This code is governed by the BSD license found in the LICENSE file.
+
+/*---
+esid: sec-temporal.plaindate.prototype.subtract
+description: Throw when the returned value from the calendar's dateAdd method is not a PlainDate.
+features: [Temporal]
+---*/
+
+class CustomCalendar extends Temporal.Calendar {
+  constructor(value) {
+    super("iso8601");
+    this.value = value;
+  }
+  dateAdd() {
+    return this.value;
+  }
+}
+
+const tests = [
+  [undefined],
+  [null, "null"],
+  [true],
+  ["2000-05"],
+  [Symbol()],
+  [200005],
+  [200005n],
+  [{}, "plain object"],
+  [() => {}, "lambda"],
+  [Temporal.PlainDate, "Temporal.PlainDate"],
+  [Temporal.PlainDate.prototype, "Temporal.PlainDate.prototype"],
+];
+for (const [test, description = typeof test] of tests) {
+  const plainDate = new Temporal.PlainDate(2000, 5, 2, new CustomCalendar(test));
+  assert.throws(TypeError, () => plainDate.subtract({ years: 1 }), `Expected error with ${description}`);
+}
diff --git a/test/built-ins/Temporal/PlainDate/prototype/subtract/custom.js b/test/built-ins/Temporal/PlainDate/prototype/subtract/custom.js
new file mode 100644
index 0000000000..33098d557e
--- /dev/null
+++ b/test/built-ins/Temporal/PlainDate/prototype/subtract/custom.js
@@ -0,0 +1,31 @@
+// Copyright (C) 2022 Igalia, S.L. All rights reserved.
+// This code is governed by the BSD license found in the LICENSE file.
+
+/*---
+esid: sec-temporal.plaindate.prototype.subtract
+description: Basic tests with custom calendar
+includes: [compareArray.js,temporalHelpers.js]
+features: [Temporal]
+---*/
+
+const result = new Temporal.PlainDate(1920, 5, 3);
+let calls = 0;
+class CustomCalendar extends Temporal.Calendar {
+  constructor() {
+    super("iso8601");
+  }
+  dateAdd(...args) {
+    ++calls;
+    assert.sameValue(args.length, 3, "Three arguments");
+    assert.sameValue(args[0], plainDate, "First argument");
+    TemporalHelpers.assertDuration(args[1], -43, 0, 0, 0, 0, 0, 0, 0, 0, 0, "Second argument");
+    assert.sameValue(typeof args[2], "object", "Third argument: type");
+    assert.sameValue(Object.getPrototypeOf(args[2]), null, "Third argument: prototype");
+    assert.compareArray(Object.keys(args[2]), [], "Third argument: keys");
+    return result;
+  }
+}
+const calendar = new CustomCalendar();
+const plainDate = new Temporal.PlainDate(1976, 11, 18, calendar);
+assert.sameValue(plainDate.subtract({ years: 43 }), result);
+assert.sameValue(calls, 1);