diff --git a/packages/twenty-server/src/database/commands/upgrade-version-command/2-5/2-5-workspace-command-1778000000000-rebuild-unique-phone-indexes.command.ts b/packages/twenty-server/src/database/commands/upgrade-version-command/2-5/2-5-workspace-command-1778000000000-rebuild-unique-phone-indexes.command.ts
index 9b6cdca5df..c0ad1778e7 100644
--- a/packages/twenty-server/src/database/commands/upgrade-version-command/2-5/2-5-workspace-command-1778000000000-rebuild-unique-phone-indexes.command.ts
+++ b/packages/twenty-server/src/database/commands/upgrade-version-command/2-5/2-5-workspace-command-1778000000000-rebuild-unique-phone-indexes.command.ts
@@ -1,6 +1,7 @@
 import { Command } from 'nest-commander';
 import { FieldMetadataType } from 'twenty-shared/types';
 import { isDefined } from 'twenty-shared/utils';
+import { isNonEmptyString } from '@sniptt/guards';
 
 import { ActiveOrSuspendedWorkspaceCommandRunner } from 'src/database/commands/command-runners/active-or-suspended-workspace.command-runner';
 import { WorkspaceIteratorService } from 'src/database/commands/command-runners/workspace-iterator.service';
@@ -10,13 +11,17 @@ import { findFlatEntityByIdInFlatEntityMaps } from 'src/engine/metadata-modules/
 import { findFlatEntityByIdInFlatEntityMapsOrThrow } from 'src/engine/metadata-modules/flat-entity/utils/find-flat-entity-by-id-in-flat-entity-maps-or-throw.util';
 import { type FlatIndexMetadata } from 'src/engine/metadata-modules/flat-index-metadata/types/flat-index-metadata.type';
 import { WorkspaceSchemaManagerService } from 'src/engine/twenty-orm/workspace-schema-manager/workspace-schema-manager.service';
+import { computeObjectTargetTable } from 'src/engine/utils/compute-object-target-table.util';
 import { WorkspaceCacheService } from 'src/engine/workspace-cache/services/workspace-cache.service';
 import {
+  computeFlatIndexFieldColumnNames,
   createIndexInWorkspaceSchema,
   dropIndexFromWorkspaceSchema,
 } from 'src/engine/workspace-manager/workspace-migration/workspace-migration-runner/action-handlers/index/utils/index-action-handler.utils';
 import { getWorkspaceSchemaName } from 'src/engine/workspace-datasource/utils/get-workspace-schema-name.util';
 
+const LEGACY_NON_EMPTY_PARTIAL_INDEX_PATTERN = /^"[a-zA-Z][a-zA-Z0-9]*" != ''$/;
+
 @RegisteredWorkspaceCommand('2.5.0', 1778000000000)
 @Command({
   name: 'upgrade:2-5:rebuild-unique-phone-indexes',
@@ -103,6 +108,35 @@ export class RebuildUniquePhoneIndexesCommand extends ActiveOrSuspendedWorkspace
           flatEntityMaps: flatObjectMetadataMaps,
         });
 
+        const hasLegacyNonEmptyPartialClause =
+          isNonEmptyString(uniquePhoneIndex.indexWhereClause) &&
+          LEGACY_NON_EMPTY_PARTIAL_INDEX_PATTERN.test(
+            uniquePhoneIndex.indexWhereClause,
+          );
+
+        if (hasLegacyNonEmptyPartialClause) {
+          const tableName = computeObjectTargetTable(flatObjectMetadata);
+          const columns = computeFlatIndexFieldColumnNames({
+            flatIndexFieldMetadatas: uniquePhoneIndex.flatIndexFieldMetadatas,
+            flatFieldMetadataMaps,
+          });
+
+          for (const column of columns) {
+            await queryRunner.query(
+              `UPDATE "${schemaName}"."${tableName}"
+                  SET "${column}" = NULL
+                WHERE "${column}" = ''`,
+            );
+          }
+
+          await queryRunner.query(
+            `UPDATE "core"."indexMetadata"
+                SET "indexWhereClause" = NULL
+              WHERE id = $1`,
+            [uniquePhoneIndex.id],
+          );
+        }
+
         await dropIndexFromWorkspaceSchema({
           indexName: uniquePhoneIndex.name,
           workspaceSchemaManagerService: this.workspaceSchemaManagerService,
@@ -110,8 +144,13 @@ export class RebuildUniquePhoneIndexesCommand extends ActiveOrSuspendedWorkspace
           schemaName,
         });
 
+        const flatIndexMetadataForRebuild: FlatIndexMetadata =
+          hasLegacyNonEmptyPartialClause
+            ? { ...uniquePhoneIndex, indexWhereClause: null }
+            : uniquePhoneIndex;
+
         await createIndexInWorkspaceSchema({
-          flatIndexMetadata: uniquePhoneIndex,
+          flatIndexMetadata: flatIndexMetadataForRebuild,
           flatObjectMetadata,
           flatFieldMetadataMaps,
           workspaceSchemaManagerService: this.workspaceSchemaManagerService,
@@ -120,7 +159,7 @@ export class RebuildUniquePhoneIndexesCommand extends ActiveOrSuspendedWorkspace
         });
 
         this.logger.log(
-          `Rebuilt unique phone index ${uniquePhoneIndex.name} for workspace ${workspaceId}`,
+          `Rebuilt unique phone index ${uniquePhoneIndex.name} for workspace ${workspaceId}${hasLegacyNonEmptyPartialClause ? ' (dropped legacy non-empty partial WHERE clause)' : ''}`,
         );
       }
       await queryRunner.commitTransaction();