diff --git a/src/plugins/chart_expressions/expression_partition_vis/common/expression_functions/__snapshots__/pie_vis_function.test.ts.snap b/src/plugins/chart_expressions/expression_partition_vis/common/expression_functions/__snapshots__/pie_vis_function.test.ts.snap
index 28d5f35c89cbf..fa82b14c33eea 100644
--- a/src/plugins/chart_expressions/expression_partition_vis/common/expression_functions/__snapshots__/pie_vis_function.test.ts.snap
+++ b/src/plugins/chart_expressions/expression_partition_vis/common/expression_functions/__snapshots__/pie_vis_function.test.ts.snap
@@ -112,7 +112,7 @@ Object {
       },
       "legendDisplay": "show",
       "legendPosition": "right",
-      "legendSize": undefined,
+      "legendSize": 80,
       "maxLegendLines": 2,
       "metric": Object {
         "accessor": 0,
@@ -246,7 +246,7 @@ Object {
       },
       "legendDisplay": "show",
       "legendPosition": "right",
-      "legendSize": undefined,
+      "legendSize": 80,
       "maxLegendLines": 2,
       "metric": Object {
         "accessor": 0,
diff --git a/src/plugins/chart_expressions/expression_partition_vis/common/expression_functions/pie_vis_function.test.ts b/src/plugins/chart_expressions/expression_partition_vis/common/expression_functions/pie_vis_function.test.ts
index 366683ce80ddb..c4b2fc1670ca0 100644
--- a/src/plugins/chart_expressions/expression_partition_vis/common/expression_functions/pie_vis_function.test.ts
+++ b/src/plugins/chart_expressions/expression_partition_vis/common/expression_functions/pie_vis_function.test.ts
@@ -31,6 +31,7 @@ describe('interpreter/functions#pieVis', () => {
     addTooltip: true,
     legendDisplay: LegendDisplay.SHOW,
     legendPosition: 'right',
+    legendSize: 80,
     isDonut: true,
     emptySizeRatio: EmptySizeRatios.SMALL,
     nestedLegend: true,
diff --git a/src/plugins/chart_expressions/expression_partition_vis/common/types/expression_renderers.ts b/src/plugins/chart_expressions/expression_partition_vis/common/types/expression_renderers.ts
index 7ac7e9deedc20..c5b7b6b16e454 100644
--- a/src/plugins/chart_expressions/expression_partition_vis/common/types/expression_renderers.ts
+++ b/src/plugins/chart_expressions/expression_partition_vis/common/types/expression_renderers.ts
@@ -84,6 +84,7 @@ export interface PieVisConfig extends VisCommonConfig {
   respectSourceOrder?: boolean;
   startFromSecondLargestSlice?: boolean;
   distinctColors?: boolean;
+  legendSize: number;
   nestedLegend: boolean;
 }
 
diff --git a/src/plugins/vis_default_editor/public/components/options/legend_size_settings.test.tsx b/src/plugins/vis_default_editor/public/components/options/legend_size_settings.test.tsx
index cc334bfaca503..d23cc24881fb9 100644
--- a/src/plugins/vis_default_editor/public/components/options/legend_size_settings.test.tsx
+++ b/src/plugins/vis_default_editor/public/components/options/legend_size_settings.test.tsx
@@ -7,7 +7,8 @@
  */
 
 import React from 'react';
-import { DEFAULT_LEGEND_SIZE, LegendSizes, LegendSizeSettings } from './legend_size_settings';
+import { LegendSizeSettings } from './legend_size_settings';
+import { LegendSizes, DEFAULT_LEGEND_SIZE } from '../../../../visualizations/public';
 import { EuiSuperSelect } from '@elastic/eui';
 import { shallow } from 'enzyme';
 
diff --git a/src/plugins/vis_default_editor/public/components/options/legend_size_settings.tsx b/src/plugins/vis_default_editor/public/components/options/legend_size_settings.tsx
index 63efb13a8a8bd..3687eb1eb8fb7 100644
--- a/src/plugins/vis_default_editor/public/components/options/legend_size_settings.tsx
+++ b/src/plugins/vis_default_editor/public/components/options/legend_size_settings.tsx
@@ -10,20 +10,11 @@ import React, { useCallback, useEffect } from 'react';
 import { i18n } from '@kbn/i18n';
 import { FormattedMessage } from '@kbn/i18n-react';
 import { EuiFormRow, EuiSuperSelect, EuiToolTip } from '@elastic/eui';
+import { LegendSizes, DEFAULT_LEGEND_SIZE } from '../../../../visualizations/public';
 
-export enum LegendSizes {
-  AUTO = '0',
-  SMALL = '80',
-  MEDIUM = '130',
-  LARGE = '180',
-  EXTRA_LARGE = '230',
-}
-
-export const DEFAULT_LEGEND_SIZE = Number(LegendSizes.MEDIUM);
-
-const legendSizeOptions: Array<{ value: LegendSizes; inputDisplay: string }> = [
+const legendSizeOptions: Array<{ value: string; inputDisplay: string }> = [
   {
-    value: LegendSizes.SMALL,
+    value: LegendSizes.SMALL.toString(),
     inputDisplay: i18n.translate(
       'visDefaultEditor.options.legendSizeSetting.legendSizeOptions.small',
       {
@@ -32,7 +23,7 @@ const legendSizeOptions: Array<{ value: LegendSizes; inputDisplay: string }> = [
     ),
   },
   {
-    value: LegendSizes.MEDIUM,
+    value: LegendSizes.MEDIUM.toString(),
     inputDisplay: i18n.translate(
       'visDefaultEditor.options.legendSizeSetting.legendSizeOptions.medium',
       {
@@ -41,7 +32,7 @@ const legendSizeOptions: Array<{ value: LegendSizes; inputDisplay: string }> = [
     ),
   },
   {
-    value: LegendSizes.LARGE,
+    value: LegendSizes.LARGE.toString(),
     inputDisplay: i18n.translate(
       'visDefaultEditor.options.legendSizeSetting.legendSizeOptions.large',
       {
@@ -50,7 +41,7 @@ const legendSizeOptions: Array<{ value: LegendSizes; inputDisplay: string }> = [
     ),
   },
   {
-    value: LegendSizes.EXTRA_LARGE,
+    value: LegendSizes.EXTRA_LARGE.toString(),
     inputDisplay: i18n.translate(
       'visDefaultEditor.options.legendSizeSetting.legendSizeOptions.extraLarge',
       {
@@ -83,7 +74,7 @@ export const LegendSizeSettings = ({
   );
 
   const options =
-    legendSize?.toString() !== LegendSizes.AUTO
+    legendSize !== LegendSizes.AUTO
       ? legendSizeOptions
       : [
           {
diff --git a/src/plugins/vis_types/heatmap/public/to_ast.ts b/src/plugins/vis_types/heatmap/public/to_ast.ts
index d6dc8a8038591..85fad86663486 100644
--- a/src/plugins/vis_types/heatmap/public/to_ast.ts
+++ b/src/plugins/vis_types/heatmap/public/to_ast.ts
@@ -11,6 +11,7 @@ import { buildExpression, buildExpressionFunction } from '../../../expressions/p
 import { getStopsWithColorsFromRanges, getStopsWithColorsFromColorsNumber } from './utils/palette';
 import type { HeatmapVisParams } from './types';
 import { getEsaggsFn } from './to_ast_esaggs';
+import { DEFAULT_LEGEND_SIZE } from '../../../visualizations/public';
 
 const DEFAULT_PERCENT_DECIMALS = 2;
 
@@ -20,7 +21,7 @@ const prepareLegend = (params: HeatmapVisParams) => {
     position: params.legendPosition,
     shouldTruncate: params.truncateLegend ?? true,
     maxLines: params.maxLegendLines ?? 1,
-    legendSize: params.legendSize,
+    legendSize: params.legendSize ?? DEFAULT_LEGEND_SIZE,
   });
 
   return buildExpression([legend]);
diff --git a/src/plugins/vis_types/pie/public/__snapshots__/to_ast.test.ts.snap b/src/plugins/vis_types/pie/public/__snapshots__/to_ast.test.ts.snap
index 904dff6ee1192..89863518c2f14 100644
--- a/src/plugins/vis_types/pie/public/__snapshots__/to_ast.test.ts.snap
+++ b/src/plugins/vis_types/pie/public/__snapshots__/to_ast.test.ts.snap
@@ -93,6 +93,9 @@ Object {
         "legendPosition": Array [
           "right",
         ],
+        "legendSize": Array [
+          130,
+        ],
         "metric": Array [
           Object {
             "chain": Array [
diff --git a/src/plugins/vis_types/pie/public/to_ast.ts b/src/plugins/vis_types/pie/public/to_ast.ts
index 37f01fcc59340..1ce6d522506d0 100644
--- a/src/plugins/vis_types/pie/public/to_ast.ts
+++ b/src/plugins/vis_types/pie/public/to_ast.ts
@@ -7,7 +7,12 @@
  */
 
 import type { PaletteOutput } from '@kbn/coloring';
-import { getVisSchemas, VisToExpressionAst, SchemaConfig } from '../../../visualizations/public';
+import {
+  getVisSchemas,
+  VisToExpressionAst,
+  SchemaConfig,
+  DEFAULT_LEGEND_SIZE,
+} from '../../../visualizations/public';
 import { buildExpression, buildExpressionFunction } from '../../../expressions/public';
 import {
   PIE_VIS_EXPRESSION_NAME,
@@ -65,7 +70,7 @@ export const toExpressionAst: VisToExpressionAst<PartitionVisParams> = async (vi
     nestedLegend: vis.params?.nestedLegend ?? false,
     truncateLegend: vis.params.truncateLegend,
     maxLegendLines: vis.params.maxLegendLines,
-    legendSize: vis.params.legendSize,
+    legendSize: vis.params.legendSize ?? DEFAULT_LEGEND_SIZE,
     distinctColors: vis.params?.distinctColors,
     isDonut: vis.params.isDonut ?? false,
     emptySizeRatio: vis.params.emptySizeRatio,
diff --git a/src/plugins/vis_types/xy/public/__snapshots__/to_ast.test.ts.snap b/src/plugins/vis_types/xy/public/__snapshots__/to_ast.test.ts.snap
index 7ee1b0d2b2053..6505b5e6250b8 100644
--- a/src/plugins/vis_types/xy/public/__snapshots__/to_ast.test.ts.snap
+++ b/src/plugins/vis_types/xy/public/__snapshots__/to_ast.test.ts.snap
@@ -32,6 +32,9 @@ Object {
     "legendPosition": Array [
       "top",
     ],
+    "legendSize": Array [
+      130,
+    ],
     "maxLegendLines": Array [
       1,
     ],
diff --git a/src/plugins/vis_types/xy/public/to_ast.ts b/src/plugins/vis_types/xy/public/to_ast.ts
index 0046a6f89a6d5..2f9bcec7f1209 100644
--- a/src/plugins/vis_types/xy/public/to_ast.ts
+++ b/src/plugins/vis_types/xy/public/to_ast.ts
@@ -13,6 +13,7 @@ import {
   getVisSchemas,
   DateHistogramParams,
   HistogramParams,
+  DEFAULT_LEGEND_SIZE,
 } from '../../../visualizations/public';
 import { buildExpression, buildExpressionFunction } from '../../../expressions/public';
 import { BUCKET_TYPES } from '../../../data/public';
@@ -210,7 +211,7 @@ export const toExpressionAst: VisToExpressionAst<VisParams> = async (vis, params
     addTimeMarker: vis.params.addTimeMarker,
     truncateLegend: vis.params.truncateLegend,
     maxLegendLines: vis.params.maxLegendLines,
-    legendSize: vis.params.legendSize,
+    legendSize: vis.params.legendSize ?? DEFAULT_LEGEND_SIZE,
     addLegend: vis.params.addLegend,
     addTooltip: vis.params.addTooltip,
     legendPosition: vis.params.legendPosition,
diff --git a/src/plugins/vis_types/xy/public/types/param.ts b/src/plugins/vis_types/xy/public/types/param.ts
index c0913226f9614..f45d35cf0923f 100644
--- a/src/plugins/vis_types/xy/public/types/param.ts
+++ b/src/plugins/vis_types/xy/public/types/param.ts
@@ -165,7 +165,7 @@ export interface XYVisConfig {
   addTimeMarker: boolean;
   truncateLegend: boolean;
   maxLegendLines: number;
-  legendSize?: number;
+  legendSize: number;
   orderBucketsBySum?: boolean;
   labels: ExpressionValueLabel;
   thresholdLine: ExpressionValueThresholdLine;
diff --git a/src/plugins/visualizations/common/constants.ts b/src/plugins/visualizations/common/constants.ts
index 0b840c8ff13fc..48382fe80e487 100644
--- a/src/plugins/visualizations/common/constants.ts
+++ b/src/plugins/visualizations/common/constants.ts
@@ -26,3 +26,13 @@ export const VisualizeConstants = {
   EDIT_BY_VALUE_PATH: '/edit_by_value',
   APP_ID: 'visualize',
 };
+
+export const LegendSizes = {
+  AUTO: 0,
+  SMALL: 80,
+  MEDIUM: 130,
+  LARGE: 180,
+  EXTRA_LARGE: 230,
+} as const;
+
+export const DEFAULT_LEGEND_SIZE = LegendSizes.MEDIUM;
diff --git a/src/plugins/visualizations/public/index.ts b/src/plugins/visualizations/public/index.ts
index 73f02a44dac13..62c32e4a539a7 100644
--- a/src/plugins/visualizations/public/index.ts
+++ b/src/plugins/visualizations/public/index.ts
@@ -56,6 +56,8 @@ export {
   VISUALIZE_ENABLE_LABS_SETTING,
   SAVED_OBJECTS_LIMIT_SETTING,
   SAVED_OBJECTS_PER_PAGE_SETTING,
+  LegendSizes,
+  DEFAULT_LEGEND_SIZE,
 } from '../common/constants';
 export type { SavedVisState, VisParams, Dimension } from '../common';
 export { prepareLogTable } from '../common';
diff --git a/x-pack/plugins/lens/server/migrations/common_migrations.ts b/x-pack/plugins/lens/server/migrations/common_migrations.ts
index 5c17e95af2a00..fdf0382eaa318 100644
--- a/x-pack/plugins/lens/server/migrations/common_migrations.ts
+++ b/x-pack/plugins/lens/server/migrations/common_migrations.ts
@@ -8,7 +8,6 @@
 import { cloneDeep, mapValues } from 'lodash';
 import type { PaletteOutput, CustomPaletteParams } from '@kbn/coloring';
 import { SerializableRecord } from '@kbn/utility-types';
-import { LegendConfig as XYLegendConfig } from '../../../../../src/plugins/chart_expressions/expression_xy/common';
 import {
   mergeMigrationFunctionMaps,
   MigrateFunction,