diff --git a/be/app/Http/Controllers/MasterTaskController.php b/be/app/Http/Controllers/MasterTaskController.php
index e18dac3..9fb87e6 100644
--- a/be/app/Http/Controllers/MasterTaskController.php
+++ b/be/app/Http/Controllers/MasterTaskController.php
@@ -26,11 +26,14 @@ class MasterTaskController extends Controller
                 continue;
             }
 
+            // get last day of month based on year and month
+            $lastDayOfMonth = date('t', strtotime($parameters['year'] . '-' . $parameters['month'] . '-01'));
+
             switch ($field) {
                 // deadline riesim, aby zobrazovalo aj mastertasky, ktore zacali v minulosti (v porovnani s prave zobrazenym mesiacom) ale deadline maju po tomto mesiaci
                 case 'month':
                     $mastertasks->whereDate('created_at', '<=',
-                        $parameters['year'] . '-' . $parameters['month'] . '-31')
+                        $parameters['year'] . '-' . $parameters['month'] . '-' . $lastDayOfMonth)
                                 ->whereDate('deadline', '>=',
                                     $parameters['year'] . '-' . $parameters['month'] . '-01');