diff --git a/frontend/src/api/hooks/useData.ts b/frontend/src/api/hooks/useData.ts
index 9a6a26d4..b5c93230 100644
--- a/frontend/src/api/hooks/useData.ts
+++ b/frontend/src/api/hooks/useData.ts
@@ -7,6 +7,7 @@ import { useState, useCallback } from 'react';
 import { dataService } from '../services';
 import type {
   SalesData,
+  SalesValidationResult,
   SalesDataQuery,
   SalesImportResult,
   DashboardStats,
@@ -52,7 +53,7 @@ export const useData = () => {
   const validateSalesData = useCallback(async (
     tenantId: string,
     file: File
-  ): Promise<SalesImportResult> => {
+  ): Promise<SalesValidationResult> => {
     try {
       setIsLoading(true);
       setError(null);
diff --git a/frontend/src/api/services/data.service.ts b/frontend/src/api/services/data.service.ts
index f238f53c..c5b7eb11 100644
--- a/frontend/src/api/services/data.service.ts
+++ b/frontend/src/api/services/data.service.ts
@@ -8,6 +8,7 @@ import { apiClient } from '../client';
 import { RequestTimeouts } from '../client/config';
 import type {
   SalesData,
+  SalesValidationResult,
   SalesDataQuery,
   SalesDataImport,
   SalesImportResult,
@@ -60,7 +61,7 @@ export class DataService {
   async validateSalesData(
     tenantId: string,
     file: File
-  ): Promise<SalesImportResult> {
+  ): Promise<SalesValidationResult> {
     const fileName = file.name.toLowerCase();
     let fileFormat: string;
 
@@ -75,11 +76,12 @@ export class DataService {
     }
 
     return apiClient.upload(
-      `/tenants/${tenantId}/sales/validate`,
+      `/tenants/${tenantId}/sales/import/validate`,
       file,
       {
         file_format: fileFormat,
         validate_only: true,
+        source: 'onboarding_upload',
       },
       {
         timeout: RequestTimeouts.MEDIUM,
diff --git a/frontend/src/api/types/data.ts b/frontend/src/api/types/data.ts
index e3583a63..cb16d3b9 100644
--- a/frontend/src/api/types/data.ts
+++ b/frontend/src/api/types/data.ts
@@ -18,6 +18,16 @@ export interface SalesData {
   external_factors?: ExternalFactors;
 }
 
+export interface SalesValidationResult {
+  is_valid: boolean;
+  total_records: number;
+  valid_records: number;
+  invalid_records: number;
+  errors: ValidationError[];
+  warnings: ValidationError[];
+  summary: Record<string, any>;
+}
+
 export interface ExternalFactors {
   weather_temperature?: number;
   weather_precipitation?: number;
diff --git a/frontend/src/pages/onboarding/OnboardingPage.tsx b/frontend/src/pages/onboarding/OnboardingPage.tsx
index fb97021a..6901bd30 100644
--- a/frontend/src/pages/onboarding/OnboardingPage.tsx
+++ b/frontend/src/pages/onboarding/OnboardingPage.tsx
@@ -125,15 +125,14 @@ const OnboardingPage: React.FC<OnboardingPageProps> = ({ user, onComplete }) =>
         try {
           // Step 2.1: First validate the CSV data
           toast.loading('Validando datos del archivo CSV...', { id: 'csv-validation' });
-          
-          const validationResult = await validateSalesData(tenantId, bakeryData.csvFile);
-          
-          toast.dismiss('csv-validation');
-          
+      
           // Check validation result
-          if (!validationResult.success) {
+          const validationResult = await validateSalesData(tenantId, bakeryData.csvFile);
+
+          // Check validation result using the correct field names
+          if (!validationResult.is_valid) {  // ← Changed from .success to .is_valid
             // Validation failed - show errors but let user decide
-            const errorMessages = validationResult.errors?.slice(0, 3).join(', ') || 'Errores de validación';
+            const errorMessages = validationResult.errors?.slice(0, 3).map(e => e.message || 'Unknown error').join(', ') || 'Errores de validación';
             const hasMoreErrors = validationResult.errors && validationResult.errors.length > 3;
             
             toast.error(
@@ -145,13 +144,13 @@ const OnboardingPage: React.FC<OnboardingPageProps> = ({ user, onComplete }) =>
             // Don't proceed with upload if validation fails
             throw new Error('Validación del CSV falló');
           }
-          
+
           // Validation passed - show summary and proceed
           if (validationResult.warnings && validationResult.warnings.length > 0) {
             toast.warn(`CSV validado con ${validationResult.warnings.length} advertencias. Continuando con la subida...`);
             console.warn('CSV validation warnings:', validationResult.warnings);
           } else {
-            toast.success('CSV validado correctamente. Procediendo con la subida...');
+            toast.success(`CSV validado correctamente. ${validationResult.valid_records} de ${validationResult.total_records} registros válidos.`);
           }
           
           // Step 2.2: Now upload the validated CSV