diff --git a/invoice.php b/invoice.php
index 437fc32c0..91f50d931 100644
--- a/invoice.php
+++ b/invoice.php
@@ -290,14 +290,32 @@
 
                                     <tr>
                                         <td>
-                                            <div class="d-print-none">
+                                            <div class="d-print-none row">
                                                 <?php if ($invoice_status !== "Paid" && $invoice_status !== "Cancelled") { ?>
                                                 <form action="post.php" method="post">
-                                                    <input type="hidden" name="invoice_id" value="<?php echo $invoice_id; ?>">
+                                                    <input type="hidden" name="item_invoice_id" value="<?php echo $invoice_id; ?>">
                                                     <input type="hidden" name="item_id" value="<?php echo $item_id; ?>">
                                                     <input type="hidden" name="item_order" value="<?php echo $item_order; ?>">
-                                                    <button class="btn btn-sm btn-light" type="submit" name="update_invoice_item_order" value="up"><i class="fa fa-fw fa-arrow-up"></i></button>
-                                                    <button class="btn btn-sm btn-light" type="submit" name="update_invoice_item_order" value="down"><i class="fa fa-fw fa-arrow-down"></i></button>
+                                                    <?php 
+                                                        // Logic to check if top or bottom arrow should be hidden
+                                                        if ($item_order == 1) {
+                                                            $up_hidden = "hidden";
+                                                        } else {
+                                                            $up_hidden = "";
+                                                        }
+
+                                                        if ($item_order == mysqli_num_rows($sql_invoice_items)) {
+                                                            $down_hidden = "hidden";
+                                                        } else {
+                                                            $down_hidden = "";
+                                                        }
+                                                    ?>
+                                                    <button class="btn btn-sm btn-light" type="submit" name="update_invoice_item_order" value="up" <?php echo $up_hidden; ?>>
+                                                        <i class="fas fa-arrow-up"></i>
+                                                    </button> 
+                                                    <button class="btn btn-sm btn-light" type="submit" name="update_invoice_item_order" value="down" <?php echo $down_hidden; ?>>
+                                                        <i class="fas fa-arrow-down"></i>
+                                                    </button>
                                                 </form>
                                                 <?php } ?>
 
diff --git a/post/invoice.php b/post/invoice.php
index d95964251..5a547b279 100644
--- a/post/invoice.php
+++ b/post/invoice.php
@@ -1085,59 +1085,37 @@
 }
 
 
-if (isset($_POST['update_invoice_item_order'])) {  
-
-    if ($_POST['update_invoice_item_order'] == 'up') {
-        $item_id = intval($_POST['item_id']);
-        $item_invoice_id = intval($_POST['item_invoice_id']);
-
-        $sql = mysqli_query($mysqli,"SELECT * FROM invoice_items WHERE item_id = $item_id");
-        $row = mysqli_fetch_array($sql);
-        $item_order = intval($row['item_order']);
-
-        $new_item_order = $item_order - 1;
-
-        //Check if new item order is used
-        $sql = mysqli_query($mysqli,"SELECT * FROM invoice_items WHERE item_invoice_id = $item_invoice_id AND item_order = $new_item_order");
-
-        //Redo the entire order of list
-        while ($row = mysqli_fetch_array($sql)) {
-            $item_id = intval($row['item_id']);
-            $item_order = intval($row['item_order']);
-
-            $new_item_order = $item_order + 1;
-
-            mysqli_query($mysqli,"UPDATE invoice_items SET item_order = $new_item_order WHERE item_id = $item_id");
-        }
-
-
-
-        mysqli_query($mysqli,"UPDATE invoice_items SET item_order = $item_order WHERE item_invoice_id = $item_invoice_id AND item_order = $new_item_order");
-        mysqli_query($mysqli,"UPDATE invoice_items SET item_order = $new_item_order WHERE item_id = $item_id");
-
-        $_SESSION['alert_message'] = "Item moved up";
-
-        header("Location: " . $_SERVER["HTTP_REFERER"]);
-
-    }
+if (isset($_POST['update_invoice_item_order'])) {
     
-    if ($_POST['update_invoice_item_order'] == 'down') {
-        $item_id = intval($_POST['item_id']);
-        $item_invoice_id = intval($_POST['item_invoice_id']);
-
-        $sql = mysqli_query($mysqli,"SELECT * FROM invoice_items WHERE item_id = $item_id");
-        $row = mysqli_fetch_array($sql);
-        $item_order = intval($row['item_order']);
+    $item_id = intval($_POST['item_id']);
+    $item_invoice_id = intval($_POST['item_invoice_id']);
 
-        $new_item_order = $item_order + 1;
+    $sql = mysqli_query($mysqli,"SELECT * FROM invoice_items WHERE item_id = $item_id");
+    $row = mysqli_fetch_array($sql);
+    $current_order = intval($row['item_order']);
+    $update_direction = sanitizeInput($_POST['update_invoice_item_order']);
+
+    switch ($update_direction)
+    {
+        case 'up':
+            $new_order = $current_order - 1;
+            break;
+        case 'down':
+            $new_order = $current_order + 1;
+            break;
+    }
 
-        mysqli_query($mysqli,"UPDATE invoice_items SET item_order = $item_order WHERE item_invoice_id = $item_invoice_id AND item_order = $new_item_order");
-        mysqli_query($mysqli,"UPDATE invoice_items SET item_order = $new_item_order WHERE item_id = $item_id");
+    //Find item_id of current item in $new_order
+    $other_sql = mysqli_query($mysqli,"SELECT * FROM invoice_items WHERE item_invoice_id = $item_invoice_id AND item_order = $new_order");
+    $other_row = mysqli_fetch_array($other_sql);
+    $other_item_id = intval($other_row['item_id']);
+    $other_row_str = strval($other_row['item_name']);
 
-        $_SESSION['alert_message'] = "Item moved down";
+    mysqli_query($mysqli,"UPDATE invoice_items SET item_order = $new_order WHERE item_id = $item_id");
 
-        header("Location: " . $_SERVER["HTTP_REFERER"]);
+    mysqli_query($mysqli,"UPDATE invoice_items SET item_order = $current_order WHERE item_id = $other_item_id");
 
-    }
+    $_SESSION['alert_message'] = "Invoice Item Order Updated";
 
+    header("Location: " . $_SERVER["HTTP_REFERER"]);
 }
\ No newline at end of file