diff --git a/Core/Lib/AjaxForms/PurchasesController.php b/Core/Lib/AjaxForms/PurchasesController.php
index dce39d33ee..d7d8137ec4 100644
--- a/Core/Lib/AjaxForms/PurchasesController.php
+++ b/Core/Lib/AjaxForms/PurchasesController.php
@@ -19,7 +19,6 @@
 
 namespace FacturaScripts\Core\Lib\AjaxForms;
 
-use FacturaScripts\Core\Base\DataBase\DataBaseWhere;
 use FacturaScripts\Core\DataSrc\Series;
 use FacturaScripts\Core\Lib\Calculator;
 use FacturaScripts\Core\Lib\ExtendedController\BaseView;
@@ -29,7 +28,10 @@
 use FacturaScripts\Core\Model\Base\BusinessDocumentLine;
 use FacturaScripts\Core\Model\Base\PurchaseDocument;
 use FacturaScripts\Core\Tools;
+use FacturaScripts\Core\Where;
 use FacturaScripts\Dinamic\Lib\AssetManager;
+use FacturaScripts\Dinamic\Model\Producto;
+use FacturaScripts\Dinamic\Model\ProductoProveedor;
 use FacturaScripts\Dinamic\Model\Proveedor;
 use FacturaScripts\Dinamic\Model\Variante;
 use Throwable;
@@ -118,8 +120,8 @@ protected function autocompleteProductAction(): bool
         $variante = new Variante();
         $query = (string)$this->request->queryOrInput('term');
         $where = [
-            new DataBaseWhere('p.bloqueado', 0),
-            new DataBaseWhere('p.secompra', 1)
+            Where::eq('p.bloqueado', 0),
+            Where::eq('p.secompra', 1)
         ];
         foreach ($variante->codeModelSearch($query, 'referencia', $where) as $value) {
             $list[] = [
@@ -128,6 +130,36 @@ protected function autocompleteProductAction(): bool
             ];
         }
 
+        // buscar también por referencia del proveedor
+        if (!empty($query)) {
+            $addedRefs = array_column($list, 'key');
+            $codproveedor = $this->request->queryOrInput('codproveedor');
+            $whereProv = [
+                Where::like('LOWER(pp.refproveedor)', strtolower($query) . '%'),
+                Where::eq('p.bloqueado', 0),
+                Where::eq('p.secompra', 1)
+            ];
+            if (!empty($codproveedor)) {
+                $whereProv[] = Where::eq('pp.codproveedor', $codproveedor);
+            }
+            $sql = 'SELECT pp.referencia, pp.refproveedor, p.descripcion'
+                . ' FROM ' . ProductoProveedor::tableName() . ' pp'
+                . ' INNER JOIN ' . Variante::tableName() . ' v ON v.referencia = pp.referencia'
+                . ' INNER JOIN ' . Producto::tableName() . ' p ON p.idproducto = v.idproducto'
+                . Where::multiSql($whereProv)
+                . ' ORDER BY pp.refproveedor ASC';
+            foreach ($this->db()->selectLimit($sql, 10) as $row) {
+                if (in_array($row['referencia'], $addedRefs)) {
+                    continue;
+                }
+                $addedRefs[] = $row['referencia'];
+                $list[] = [
+                    'key' => Tools::fixHtml($row['referencia']),
+                    'value' => Tools::fixHtml($row['refproveedor'] . ' - ' . $row['descripcion'])
+                ];
+            }
+        }
+
         if (empty($list)) {
             $list[] = ['key' => null, 'value' => Tools::trans('no-data')];
         }
@@ -346,6 +378,7 @@ protected function recalculateAction(bool $renderLines): bool
         $formData = json_decode($this->request->input('data'), true);
         PurchasesHeaderHTML::apply($model, $formData);
         PurchasesFooterHTML::apply($model, $formData);
+        $this->resolveSupplierRefs($formData, $model->codproveedor);
         PurchasesLineHTML::apply($model, $lines, $formData);
         Calculator::calculate($model, $lines, false);
 
@@ -515,6 +548,42 @@ protected function saveStatusAction(): bool
         return false;
     }
 
+    private function resolveSupplierRef(string $reference, string $codproveedor): string
+    {
+        $variant = new Variante();
+        if ($variant->loadWhere([Where::eq('referencia', $reference)])) {
+            return $reference;
+        }
+
+        $where = [Where::eq('refproveedor', $reference)];
+        if (!empty($codproveedor)) {
+            $where[] = Where::eq('codproveedor', $codproveedor);
+        }
+        $rows = ProductoProveedor::all($where, [], 0, 1);
+        return empty($rows) ? $reference : $rows[0]->referencia;
+    }
+
+    private function resolveSupplierRefs(array &$formData, string $codproveedor): void
+    {
+        foreach ($formData as $key => $value) {
+            if (!empty($value) && str_starts_with($key, 'referencia_n')) {
+                $formData[$key] = $this->resolveSupplierRef((string)$value, $codproveedor);
+            }
+        }
+
+        if (!empty($formData['selectedLine'])) {
+            $formData['selectedLine'] = $this->resolveSupplierRef((string)$formData['selectedLine'], $codproveedor);
+        }
+
+        if (($formData['action'] ?? '') === 'fast-line' && !empty($formData['fastli'])) {
+            $resolved = $this->resolveSupplierRef((string)$formData['fastli'], $codproveedor);
+            if ($resolved !== $formData['fastli']) {
+                $formData['action'] = 'fast-product';
+                $formData['selectedLine'] = $resolved;
+            }
+        }
+    }
+
     private function sendJsonWithLogs(array $data): void
     {
         $data['messages'] = Tools::log()::read('master', $this->logLevels);
diff --git a/Core/View/Tab/PurchasesDocument.html.twig b/Core/View/Tab/PurchasesDocument.html.twig
index 922c1e9887..daf6b158c4 100644
--- a/Core/View/Tab/PurchasesDocument.html.twig
+++ b/Core/View/Tab/PurchasesDocument.html.twig
@@ -37,7 +37,7 @@
                 $.ajax({
                     method: "POST",
                     url: '{{ fsc.url() }}',
-                    data: {action: 'autocomplete-product', term: request.term},
+                    data: {action: 'autocomplete-product', term: request.term, codproveedor: document.forms['purchasesForm']['codproveedor'] ? document.forms['purchasesForm']['codproveedor'].value : ''},
                     dataType: "json",
                     success: function (results) {
                         let values = [];