diff --git a/app/Http/Requests/Invoice/StoreInvoiceRequest.php b/app/Http/Requests/Invoice/StoreInvoiceRequest.php
index 5d8555bd9530..0a6ec1bea64f 100644
--- a/app/Http/Requests/Invoice/StoreInvoiceRequest.php
+++ b/app/Http/Requests/Invoice/StoreInvoiceRequest.php
@@ -47,12 +47,14 @@ class StoreInvoiceRequest extends Request
             $rules['documents'] = 'file|mimes:png,ai,svg,jpeg,tiff,pdf,gif,psd,txt,doc,xls,ppt,xlsx,docx,pptx|max:20000';
         }
 
-        $rules['client_id'] = 'required|exists:clients,id,company_id,'.auth()->user()->company()->id;
+        $rules['client_id'] = 'bail|required|exists:clients,id,company_id,'.auth()->user()->company()->id;
 
         $rules['invitations.*.client_contact_id'] = 'distinct';
 
         $rules['number'] = new UniqueInvoiceNumberRule($this->all());
 
+        $rules['project_id'] = 'bail|sometimes|' . new ValidProjectForClient($this->all());
+
         return $rules;
     }
 
@@ -68,6 +70,10 @@ class StoreInvoiceRequest extends Request
             $input['client_id'] = $this->decodePrimaryKey($input['client_id']);
         }
 
+        if (array_key_exists('project_id', $input) && is_string($input['project_id'])) {
+            $input['project_id'] = $this->decodePrimaryKey($input['project_id']);
+        }
+
         if (array_key_exists('assigned_user_id', $input) && is_string($input['assigned_user_id'])) {
             $input['assigned_user_id'] = $this->decodePrimaryKey($input['assigned_user_id']);
         }
diff --git a/app/Http/ValidationRules/Project/ValidProjectForClient.php b/app/Http/ValidationRules/Project/ValidProjectForClient.php
new file mode 100644
index 000000000000..a23e421de398
--- /dev/null
+++ b/app/Http/ValidationRules/Project/ValidProjectForClient.php
@@ -0,0 +1,55 @@
+<?php
+/**
+ * Invoice Ninja (https://invoiceninja.com).
+ *
+ * @link https://github.com/invoiceninja/invoiceninja source repository
+ *
+ * @copyright Copyright (c) 2020. Invoice Ninja LLC (https://invoiceninja.com)
+ *
+ * @license https://opensource.org/licenses/AAL
+ */
+
+namespace App\Http\ValidationRules\Project;
+
+use App\Models\Project;
+use App\Utils\Traits\MakesHash;
+use Illuminate\Contracts\Validation\Rule;
+
+/**
+ * Class ValidProjectForClient.
+ */
+class ValidProjectForClient implements Rule
+{
+    use MakesHash;
+
+    public $input;
+
+    public function __construct($input)
+    {
+        $this->input = $input;
+    }
+    /**
+     * @param string $attribute
+     * @param mixed $value
+     * @return bool
+     */
+    public function passes($attribute, $value)
+    {
+        if(is_string($this->input['project_id']))
+            $this->input['project_id'] = $this->decodePrimaryKey($this->input['project_id']);
+
+        $project = Project::findOrFail($this->input['project_id']);
+
+        return $project->client_id == $this->input['client_id'];
+    }
+
+    /**
+     * @return string
+     */
+    public function message()
+    {
+        return "Project client does not match entity client";
+    }
+
+
+}