diff --git a/x-pack/plugins/security_solution/public/common/mock/timeline_results.ts b/x-pack/plugins/security_solution/public/common/mock/timeline_results.ts
index 732097aedbc2b..fe8ec46b752c5 100644
--- a/x-pack/plugins/security_solution/public/common/mock/timeline_results.ts
+++ b/x-pack/plugins/security_solution/public/common/mock/timeline_results.ts
@@ -1947,6 +1947,11 @@ const mockTimelineModelColumns: TimelineModel['columns'] = [
     id: 'user.name',
     initialWidth: 180,
   },
+  {
+    columnHeaderType: 'not-filtered',
+    id: 'kibana.alert.workflow_assignee_ids',
+    initialWidth: 180,
+  },
 ];
 export const mockTimelineModel: TimelineModel = {
   activeTab: TimelineTabs.query,
diff --git a/x-pack/plugins/security_solution/public/detections/components/alerts_table/default_config.test.tsx b/x-pack/plugins/security_solution/public/detections/components/alerts_table/default_config.test.tsx
index b4b0a07fd7ab2..fc5d91bcaf8e5 100644
--- a/x-pack/plugins/security_solution/public/detections/components/alerts_table/default_config.test.tsx
+++ b/x-pack/plugins/security_solution/public/detections/components/alerts_table/default_config.test.tsx
@@ -6,16 +6,78 @@
  */
 
 import type { ExistsFilter, Filter } from '@kbn/es-query';
+import { tableDefaults } from '@kbn/securitysolution-data-table';
+import { createLicenseServiceMock } from '../../../../common/license/mocks';
 import {
   buildAlertAssigneesFilter,
   buildAlertsFilter,
   buildAlertStatusesFilter,
   buildAlertStatusFilter,
   buildThreatMatchFilter,
+  getAlertsDefaultModel,
+  getAlertsPreviewDefaultModel,
 } from './default_config';
 
 jest.mock('./actions');
 
+const basicBaseColumns = [
+  {
+    columnHeaderType: 'not-filtered',
+    displayAsText: 'Severity',
+    id: 'kibana.alert.severity',
+    initialWidth: 105,
+  },
+  {
+    columnHeaderType: 'not-filtered',
+    displayAsText: 'Risk Score',
+    id: 'kibana.alert.risk_score',
+    initialWidth: 100,
+  },
+  {
+    columnHeaderType: 'not-filtered',
+    displayAsText: 'Reason',
+    id: 'kibana.alert.reason',
+    initialWidth: 450,
+  },
+  { columnHeaderType: 'not-filtered', id: 'host.name' },
+  { columnHeaderType: 'not-filtered', id: 'user.name' },
+  { columnHeaderType: 'not-filtered', id: 'process.name' },
+  { columnHeaderType: 'not-filtered', id: 'file.name' },
+  { columnHeaderType: 'not-filtered', id: 'source.ip' },
+  { columnHeaderType: 'not-filtered', id: 'destination.ip' },
+];
+
+const platinumBaseColumns = [
+  {
+    columnHeaderType: 'not-filtered',
+    displayAsText: 'Severity',
+    id: 'kibana.alert.severity',
+    initialWidth: 105,
+  },
+  {
+    columnHeaderType: 'not-filtered',
+    displayAsText: 'Risk Score',
+    id: 'kibana.alert.risk_score',
+    initialWidth: 100,
+  },
+  {
+    columnHeaderType: 'not-filtered',
+    displayAsText: 'Reason',
+    id: 'kibana.alert.reason',
+    initialWidth: 450,
+  },
+  { columnHeaderType: 'not-filtered', id: 'host.name' },
+  { columnHeaderType: 'not-filtered', id: 'host.risk.calculated_level' },
+  { columnHeaderType: 'not-filtered', id: 'user.name' },
+  { columnHeaderType: 'not-filtered', id: 'user.risk.calculated_level' },
+  { columnHeaderType: 'not-filtered', id: 'kibana.alert.host.criticality_level' },
+  { columnHeaderType: 'not-filtered', id: 'kibana.alert.user.criticality_level' },
+  { columnHeaderType: 'not-filtered', id: 'process.name' },
+  { columnHeaderType: 'not-filtered', id: 'file.name' },
+  { columnHeaderType: 'not-filtered', id: 'source.ip' },
+  { columnHeaderType: 'not-filtered', id: 'destination.ip' },
+];
+
 describe('alerts default_config', () => {
   describe('buildAlertsRuleIdFilter', () => {
     test('given a rule id this will return an array with a single filter', () => {
@@ -200,6 +262,122 @@ describe('alerts default_config', () => {
     });
   });
 
+  describe('getAlertsDefaultModel', () => {
+    test('returns correct model for Basic license', () => {
+      const licenseServiceMock = createLicenseServiceMock();
+      licenseServiceMock.isPlatinumPlus.mockReturnValue(false);
+      const model = getAlertsDefaultModel(licenseServiceMock);
+
+      const expected = {
+        ...tableDefaults,
+        showCheckboxes: true,
+        columns: [
+          { columnHeaderType: 'not-filtered', id: '@timestamp', initialWidth: 200 },
+          {
+            columnHeaderType: 'not-filtered',
+            displayAsText: 'Rule',
+            id: 'kibana.alert.rule.name',
+            initialWidth: 180,
+            linkField: 'kibana.alert.rule.uuid',
+          },
+          {
+            columnHeaderType: 'not-filtered',
+            displayAsText: 'Assignees',
+            id: 'kibana.alert.workflow_assignee_ids',
+            initialWidth: 190,
+          },
+          ...basicBaseColumns,
+        ],
+      };
+      expect(model).toEqual(expected);
+    });
+
+    test('returns correct model for Platinum license', () => {
+      const licenseServiceMock = createLicenseServiceMock();
+      const model = getAlertsDefaultModel(licenseServiceMock);
+
+      const expected = {
+        ...tableDefaults,
+        showCheckboxes: true,
+        columns: [
+          { columnHeaderType: 'not-filtered', id: '@timestamp', initialWidth: 200 },
+          {
+            columnHeaderType: 'not-filtered',
+            displayAsText: 'Rule',
+            id: 'kibana.alert.rule.name',
+            initialWidth: 180,
+            linkField: 'kibana.alert.rule.uuid',
+          },
+          {
+            columnHeaderType: 'not-filtered',
+            displayAsText: 'Assignees',
+            id: 'kibana.alert.workflow_assignee_ids',
+            initialWidth: 190,
+          },
+          ...platinumBaseColumns,
+        ],
+      };
+      expect(model).toEqual(expected);
+    });
+  });
+
+  describe('getAlertsPreviewDefaultModel', () => {
+    test('returns correct model for Basic license', () => {
+      const licenseServiceMock = createLicenseServiceMock();
+      licenseServiceMock.isPlatinumPlus.mockReturnValue(false);
+      const model = getAlertsPreviewDefaultModel(licenseServiceMock);
+
+      const expected = {
+        ...tableDefaults,
+        showCheckboxes: false,
+        defaultColumns: [
+          { columnHeaderType: 'not-filtered', id: 'kibana.alert.original_time', initialWidth: 200 },
+          ...basicBaseColumns,
+        ],
+        columns: [
+          { columnHeaderType: 'not-filtered', id: 'kibana.alert.original_time', initialWidth: 200 },
+          ...basicBaseColumns,
+        ],
+        sort: [
+          {
+            columnId: 'kibana.alert.original_time',
+            columnType: 'date',
+            esTypes: ['date'],
+            sortDirection: 'desc',
+          },
+        ],
+      };
+      expect(model).toEqual(expected);
+    });
+
+    test('returns correct model for Platinum license', () => {
+      const licenseServiceMock = createLicenseServiceMock();
+      const model = getAlertsPreviewDefaultModel(licenseServiceMock);
+
+      const expected = {
+        ...tableDefaults,
+        showCheckboxes: false,
+        defaultColumns: [
+          { columnHeaderType: 'not-filtered', id: 'kibana.alert.original_time', initialWidth: 200 },
+          ...platinumBaseColumns,
+        ],
+        columns: [
+          { columnHeaderType: 'not-filtered', id: 'kibana.alert.original_time', initialWidth: 200 },
+          ...platinumBaseColumns,
+        ],
+        sort: [
+          {
+            columnId: 'kibana.alert.original_time',
+            columnType: 'date',
+            esTypes: ['date'],
+            sortDirection: 'desc',
+          },
+        ],
+      };
+      expect(model).toEqual(expected);
+    });
+  });
+
   // TODO: move these tests to ../timelines/components/timeline/body/events/event_column_view.tsx
   // describe.skip('getAlertActions', () => {
   //   let setEventsLoading: ({ eventIds, isLoading }: SetEventsLoadingProps) => void;
diff --git a/x-pack/plugins/security_solution/public/detections/components/alerts_table/default_config.tsx b/x-pack/plugins/security_solution/public/detections/components/alerts_table/default_config.tsx
index 6065e617c1254..9db07f4824652 100644
--- a/x-pack/plugins/security_solution/public/detections/components/alerts_table/default_config.tsx
+++ b/x-pack/plugins/security_solution/public/detections/components/alerts_table/default_config.tsx
@@ -192,7 +192,7 @@ export const getAlertsDefaultModel = (license?: LicenseService): SubsetDataTable
 
 export const getAlertsPreviewDefaultModel = (license?: LicenseService): SubsetDataTableModel => ({
   ...getAlertsDefaultModel(license),
-  columns: getColumns(license),
+  columns: getRulePreviewColumns(license),
   defaultColumns: getRulePreviewColumns(license),
   sort: [
     {
diff --git a/x-pack/plugins/security_solution/public/detections/configurations/security_solution_detections/columns.ts b/x-pack/plugins/security_solution/public/detections/configurations/security_solution_detections/columns.ts
index 384c6bf955e51..b22bf5e2ed429 100644
--- a/x-pack/plugins/security_solution/public/detections/configurations/security_solution_detections/columns.ts
+++ b/x-pack/plugins/security_solution/public/detections/configurations/security_solution_detections/columns.ts
@@ -25,6 +25,13 @@ import {
   DEFAULT_TABLE_DATE_COLUMN_MIN_WIDTH,
 } from './translations';
 
+export const assigneesColumn: ColumnHeaderOptions = {
+  columnHeaderType: defaultColumnHeaderType,
+  displayAsText: i18n.ALERTS_HEADERS_ASSIGNEES,
+  id: 'kibana.alert.workflow_assignee_ids',
+  initialWidth: DEFAULT_DATE_COLUMN_MIN_WIDTH,
+};
+
 const getBaseColumns = (
   license?: LicenseService
 ): Array<
@@ -32,12 +39,6 @@ const getBaseColumns = (
 > => {
   const isPlatinumPlus = license?.isPlatinumPlus?.() ?? false;
   return [
-    {
-      columnHeaderType: defaultColumnHeaderType,
-      displayAsText: i18n.ALERTS_HEADERS_ASSIGNEES,
-      id: 'kibana.alert.workflow_assignee_ids',
-      initialWidth: DEFAULT_DATE_COLUMN_MIN_WIDTH,
-    },
     {
       columnHeaderType: defaultColumnHeaderType,
       displayAsText: i18n.ALERTS_HEADERS_SEVERITY,
@@ -131,6 +132,7 @@ export const getColumns = (
     initialWidth: DEFAULT_COLUMN_MIN_WIDTH,
     linkField: 'kibana.alert.rule.uuid',
   },
+  assigneesColumn,
   ...getBaseColumns(license),
 ];
 
diff --git a/x-pack/plugins/security_solution/public/timelines/containers/local_storage/index.test.ts b/x-pack/plugins/security_solution/public/timelines/containers/local_storage/index.test.ts
index f715169e2abb9..94f03268a23b2 100644
--- a/x-pack/plugins/security_solution/public/timelines/containers/local_storage/index.test.ts
+++ b/x-pack/plugins/security_solution/public/timelines/containers/local_storage/index.test.ts
@@ -16,6 +16,7 @@ import {
   addTableInStorage,
   migrateAlertTableStateToTriggerActionsState,
   migrateTriggerActionsVisibleColumnsAlertTable88xTo89,
+  addAssigneesSpecsToSecurityDataTableIfNeeded,
 } from '.';
 
 import { mockDataTableModel, createSecuritySolutionStorageMock } from '../../../common/mock';
@@ -566,6 +567,12 @@ describe('SiemLocalStorage', () => {
           { columnHeaderType: 'not-filtered', id: 'file.name' },
           { columnHeaderType: 'not-filtered', id: 'source.ip' },
           { columnHeaderType: 'not-filtered', id: 'destination.ip' },
+          {
+            columnHeaderType: 'not-filtered',
+            displayAsText: 'Assignees',
+            id: 'kibana.alert.workflow_assignee_ids',
+            initialWidth: 190,
+          },
         ],
         defaultColumns: [
           { columnHeaderType: 'not-filtered', id: '@timestamp', initialWidth: 200 },
@@ -600,6 +607,12 @@ describe('SiemLocalStorage', () => {
           { columnHeaderType: 'not-filtered', id: 'file.name' },
           { columnHeaderType: 'not-filtered', id: 'source.ip' },
           { columnHeaderType: 'not-filtered', id: 'destination.ip' },
+          {
+            columnHeaderType: 'not-filtered',
+            displayAsText: 'Assignees',
+            id: 'kibana.alert.workflow_assignee_ids',
+            initialWidth: 190,
+          },
         ],
         dataViewId: 'security-solution-default',
         deletedEventIds: [],
@@ -1527,4 +1540,88 @@ describe('SiemLocalStorage', () => {
       ).toBeNull();
     });
   });
+
+  describe('addMissingColumnsToSecurityDataTable', () => {
+    it('should add missing "Assignees" column specs', () => {
+      const dataTableState: DataTableState['dataTable']['tableById'] = {
+        'alerts-page': {
+          columns: [{ columnHeaderType: 'not-filtered', id: '@timestamp', initialWidth: 200 }],
+          defaultColumns: [
+            { columnHeaderType: 'not-filtered', id: 'host.name' },
+            { columnHeaderType: 'not-filtered', id: 'user.name' },
+            { columnHeaderType: 'not-filtered', id: 'process.name' },
+          ],
+          isLoading: false,
+          queryFields: [],
+          dataViewId: 'security-solution-default',
+          deletedEventIds: [],
+          expandedDetail: {},
+          filters: [],
+          indexNames: ['.alerts-security.alerts-default'],
+          isSelectAllChecked: false,
+          itemsPerPage: 25,
+          itemsPerPageOptions: [10, 25, 50, 100],
+          loadingEventIds: [],
+          showCheckboxes: true,
+          sort: [
+            {
+              columnId: '@timestamp',
+              columnType: 'date',
+              esTypes: ['date'],
+              sortDirection: 'desc',
+            },
+          ],
+          graphEventId: undefined,
+          selectedEventIds: {},
+          sessionViewConfig: null,
+          selectAll: false,
+          id: 'alerts-page',
+          title: '',
+          initialized: true,
+          updated: 1665943295913,
+          totalCount: 0,
+          viewMode: VIEW_SELECTION.gridView,
+          additionalFilters: {
+            showBuildingBlockAlerts: false,
+            showOnlyThreatIndicatorAlerts: false,
+          },
+        },
+      };
+      storage.set(LOCAL_STORAGE_TABLE_KEY, dataTableState);
+      migrateAlertTableStateToTriggerActionsState(storage, dataTableState);
+      migrateTriggerActionsVisibleColumnsAlertTable88xTo89(storage);
+
+      const expectedColumns = [
+        { columnHeaderType: 'not-filtered', id: '@timestamp', initialWidth: 200 },
+        {
+          columnHeaderType: 'not-filtered',
+          displayAsText: 'Assignees',
+          id: 'kibana.alert.workflow_assignee_ids',
+          initialWidth: 190,
+        },
+      ];
+      const expectedDefaultColumns = [
+        { columnHeaderType: 'not-filtered', id: 'host.name' },
+        { columnHeaderType: 'not-filtered', id: 'user.name' },
+        { columnHeaderType: 'not-filtered', id: 'process.name' },
+        {
+          columnHeaderType: 'not-filtered',
+          displayAsText: 'Assignees',
+          id: 'kibana.alert.workflow_assignee_ids',
+          initialWidth: 190,
+        },
+      ];
+
+      addAssigneesSpecsToSecurityDataTableIfNeeded(storage, dataTableState);
+
+      expect(dataTableState['alerts-page'].columns).toMatchObject(expectedColumns);
+      expect(dataTableState['alerts-page'].defaultColumns).toMatchObject(expectedDefaultColumns);
+
+      const tableKey = 'detection-engine-alert-table-securitySolution-alerts-page-gridView';
+      expect(storage.get(tableKey)).toMatchObject({
+        columns: expectedColumns,
+        visibleColumns: expectedColumns.map((col) => col.id),
+      });
+    });
+  });
 });
diff --git a/x-pack/plugins/security_solution/public/timelines/containers/local_storage/index.tsx b/x-pack/plugins/security_solution/public/timelines/containers/local_storage/index.tsx
index bab84294e0a67..8191f800ff934 100644
--- a/x-pack/plugins/security_solution/public/timelines/containers/local_storage/index.tsx
+++ b/x-pack/plugins/security_solution/public/timelines/containers/local_storage/index.tsx
@@ -12,8 +12,9 @@ import type {
   DataTableModel,
   TableIdLiteral,
 } from '@kbn/securitysolution-data-table';
-import { TableId } from '@kbn/securitysolution-data-table';
+import { tableEntity, TableEntityType, TableId } from '@kbn/securitysolution-data-table';
 import type { ColumnHeaderOptions } from '@kbn/timelines-plugin/common';
+import { assigneesColumn } from '../../../detections/configurations/security_solution_detections/columns';
 import { ALERTS_TABLE_REGISTRY_CONFIG_IDS, VIEW_SELECTION } from '../../../../common/constants';
 import type { DataTablesStorage } from './types';
 import { useKibana } from '../../../common/lib/kibana';
@@ -195,6 +196,90 @@ export const migrateColumnLabelToDisplayAsText = (
     : {}),
 });
 
+/**
+ * Adds "Assignees" column and makes it visible in alerts table
+ */
+const addAssigneesColumnToAlertsTable = (storage: Storage) => {
+  const localStorageKeys = [
+    `detection-engine-alert-table-${ALERTS_TABLE_REGISTRY_CONFIG_IDS.ALERTS_PAGE}-gridView`,
+    `detection-engine-alert-table-${ALERTS_TABLE_REGISTRY_CONFIG_IDS.RULE_DETAILS}-gridView`,
+  ];
+
+  localStorageKeys.forEach((key) => {
+    const alertTableData = storage.get(key);
+    if (!alertTableData) {
+      return;
+    }
+    // Make "Assignees" field selected in the table
+    if ('columns' in alertTableData) {
+      let updatedAlertsTableState = false;
+      const columns =
+        alertTableData.columns as DataTableState['dataTable']['tableById'][string]['columns'];
+      const hasAssigneesColumn = columns.findIndex((col) => col.id === assigneesColumn.id) !== -1;
+      if (!hasAssigneesColumn) {
+        // Insert "Assignees" column at the index 1 to mimic behaviour of adding field to alerts table
+        alertTableData.columns.splice(1, 0, assigneesColumn);
+        updatedAlertsTableState = true;
+      }
+      // Make "Assignees" column visible in the table
+      if ('visibleColumns' in alertTableData) {
+        const visibleColumns = alertTableData.visibleColumns as string[];
+        const assigneesColumnExists =
+          visibleColumns.findIndex((col) => col === assigneesColumn.id) !== -1;
+        if (!assigneesColumnExists) {
+          alertTableData.visibleColumns.splice(1, 0, assigneesColumn.id);
+          updatedAlertsTableState = true;
+        }
+      }
+      if (updatedAlertsTableState) {
+        storage.set(key, alertTableData);
+      }
+    }
+  });
+};
+
+/**
+ * Adds "Assignees" column specs to table data model
+ */
+export const addAssigneesSpecsToSecurityDataTableIfNeeded = (
+  storage: Storage,
+  dataTableState: DataTableState['dataTable']['tableById']
+) => {
+  // Add "Assignees" column specs to the table data model
+  let updatedTableModel = false;
+  for (const [tableId, tableModel] of Object.entries(dataTableState)) {
+    // Only add "Assignees" column specs to alerts tables
+    if (tableEntity[tableId as TableId] !== TableEntityType.alert) {
+      // eslint-disable-next-line no-continue
+      continue;
+    }
+
+    // We added a new base column for "Assignees" in 8.12
+    // In order to show correct custom header label after user upgrades to 8.12 we need to make sure the appropriate specs are in the table model.
+    const columns = tableModel.columns;
+    if (Array.isArray(columns)) {
+      const hasAssigneesColumn = columns.findIndex((col) => col.id === assigneesColumn.id) !== -1;
+      if (!hasAssigneesColumn) {
+        updatedTableModel = true;
+        tableModel.columns.push(assigneesColumn);
+      }
+    }
+    const defaultColumns = tableModel.defaultColumns;
+    if (defaultColumns) {
+      const hasAssigneesColumn =
+        defaultColumns.findIndex((col) => col.id === assigneesColumn.id) !== -1;
+      if (!hasAssigneesColumn) {
+        updatedTableModel = true;
+        tableModel.defaultColumns.push(assigneesColumn);
+      }
+    }
+  }
+  if (updatedTableModel) {
+    storage.set(LOCAL_STORAGE_TABLE_KEY, dataTableState);
+    addAssigneesColumnToAlertsTable(storage);
+  }
+};
+
 export const getDataTablesInStorageByIds = (storage: Storage, tableIds: TableIdLiteral[]) => {
   let allDataTables = storage.get(LOCAL_STORAGE_TABLE_KEY);
   const legacyTimelineTables = storage.get(LOCAL_STORAGE_TIMELINE_KEY_LEGACY);
@@ -209,6 +294,7 @@ export const getDataTablesInStorageByIds = (storage: Storage, tableIds: TableIdL
 
   migrateAlertTableStateToTriggerActionsState(storage, allDataTables);
   migrateTriggerActionsVisibleColumnsAlertTable88xTo89(storage);
+  addAssigneesSpecsToSecurityDataTableIfNeeded(storage, allDataTables);
 
   return tableIds.reduce((acc, tableId) => {
     const tableModel = allDataTables[tableId];