diff --git a/addons/project/static/tests/project_task_groupby_tests.js b/addons/project/static/tests/project_task_groupby_tests.js
index 8ae0f747b88..059792c78d1 100644
--- a/addons/project/static/tests/project_task_groupby_tests.js
+++ b/addons/project/static/tests/project_task_groupby_tests.js
@@ -18,11 +18,23 @@ QUnit.module("Project", (hooks) => {
                     type: "many2one",
                     relation: "project.project",
                 },
+                user_ids: {
+                    string: "Assignees",
+                    type: "many2many",
+                    relation: "project.task",
+                },
+                date_deadline: {
+                    string: "Deadline",
+                    type: "date",
+                }
             },
             records: [{
                 id: 1,
                 display_name: "My task",
                 project_id: false,
+                user_ids: [],
+                date_deadline: false,
+
             }],
         };
         target = getFixture();
@@ -47,6 +59,43 @@ QUnit.module("Project", (hooks) => {
 
         assert.strictEqual(target.querySelector(".o_group_name").innerText, "🔒 Private (1)");
     });
+    QUnit.test("Test group label for empty assignees in tree", async function (assert) {
+        assert.expect(1);
+
+        const views = {
+            "project.task,false,list":
+                `<tree js_class="project_task_list"/>`,
+        };
+        const { openView } = await start({
+            serverData: { views },
+        });
+        await openView({
+            res_model: "project.task",
+            views: [[false, "tree"]],
+            context: { group_by: ["user_ids"] },
+        });
+
+        assert.strictEqual(target.querySelector(".o_group_name").innerText, "👤 Unassigned (1)");
+    });
+
+    QUnit.test("Test group label for empty deadline in tree", async function (assert) {
+        assert.expect(1);
+
+        const views = {
+            "project.task,false,list":
+                `<tree js_class="project_task_list"/>`,
+        };
+        const { openView } = await start({
+            serverData: { views },
+        });
+        await openView({
+            res_model: "project.task",
+            views: [[false, "tree"]],
+            context: { group_by: ["date_deadline"] },
+        });
+
+        assert.strictEqual(target.querySelector(".o_group_name").innerText, "None (1)");
+    });
 
     QUnit.test("Test group label for empty project in kanban", async function (assert) {
         assert.expect(1);
@@ -70,6 +119,50 @@ QUnit.module("Project", (hooks) => {
         assert.strictEqual(target.querySelector(".o_column_title").innerText, "🔒 Private\n1");
     });
 
+    QUnit.test("Test group label for empty assignees in kanban", async function (assert) {
+        assert.expect(1);
+
+        const views = {
+            "project.task,false,kanban":
+                `<kanban js_class="project_task_kanban" default_group_by="user_ids">
+                    <templates>
+                        <t t-name="kanban-box"/>
+                    </templates>
+                </kanban>`,
+        };
+        const { openView } = await start({
+            serverData: { views },
+        });
+        await openView({
+            res_model: "project.task",
+            views: [[false, "kanban"]],
+        });
+
+        assert.strictEqual(target.querySelector(".o_column_title").innerText, "👤 Unassigned\n1");
+    });
+
+    QUnit.test("Test group label for empty deadline in kanban", async function (assert) {
+        assert.expect(1);
+
+        const views = {
+            "project.task,false,kanban":
+                `<kanban js_class="project_task_kanban" default_group_by="date_deadline">
+                    <templates>
+                        <t t-name="kanban-box"/>
+                    </templates>
+                </kanban>`,
+        };
+        const { openView } = await start({
+            serverData: { views },
+        });
+        await openView({
+            res_model: "project.task",
+            views: [[false, "kanban"]],
+        });
+
+        assert.strictEqual(target.querySelector(".o_column_title").innerText, "None");
+    });
+
     QUnit.test("Test group label for empty project in pivot", async function (assert) {
         assert.expect(1);
 
@@ -92,4 +185,50 @@ QUnit.module("Project", (hooks) => {
             "Private",
         );
     });
+
+    QUnit.test("Test group label for empty assignees in pivot", async function (assert) {
+        assert.expect(1);
+
+        const views = {
+            "project.task,false,pivot":
+                `<pivot js_class="project_pivot">
+                    <field name="user_ids" type="row"/>
+                </pivot>`,
+        };
+        const { openView } = await start({
+            serverData: { views },
+        });
+        await openView({
+            res_model: "project.task",
+            views: [[false, "pivot"]],
+        });
+
+        assert.strictEqual(
+            target.querySelector("tr:nth-of-type(2) .o_pivot_header_cell_closed").innerText,
+            "Unassigned",
+        );
+    });
+
+    QUnit.test("Test group label for empty deadline in pivot", async function (assert) {
+        assert.expect(1);
+
+        const views = {
+            "project.task,false,pivot":
+                `<pivot js_class="project_pivot">
+                    <field name="date_deadline" type="row"/>
+                </pivot>`,
+        };
+        const { openView } = await start({
+            serverData: { views },
+        });
+        await openView({
+            res_model: "project.task",
+            views: [[false, "pivot"]],
+        });
+
+        assert.strictEqual(
+            target.querySelector("tr:nth-of-type(2) .o_pivot_header_cell_closed").innerText,
+            "None",
+        );
+    });
 });
diff --git a/addons/web/static/src/views/pivot/pivot_model.js b/addons/web/static/src/views/pivot/pivot_model.js
index 401178f09de..29e0f94b8e8 100644
--- a/addons/web/static/src/views/pivot/pivot_model.js
+++ b/addons/web/static/src/views/pivot/pivot_model.js
@@ -1554,7 +1554,7 @@ export class PivotModel extends Model {
                 : this.env._t("No");
         }
         if (value === false) {
-            return this._getEmptyGroupLabel(groupBy);
+            return this._getEmptyGroupLabel(fieldName);
         }
         if (value instanceof Array) {
             return this._getNumberedLabel(value, fieldName, config);