diff --git a/src/Library/Economy/Payment/WalletGatewayService.php b/src/Library/Economy/Payment/WalletGatewayService.php
new file mode 100644
index 0000000..63fa5a8
--- /dev/null
+++ b/src/Library/Economy/Payment/WalletGatewayService.php
@@ -0,0 +1,44 @@
+<?php
+
+namespace App\Library\Economy\Payment;
+
+use App\Entity\Accounting;
+use App\Entity\Money;
+use App\Entity\WalletStatementDirection;
+use App\Repository\WalletStatementRepository;
+use Brick\Money as Brick;
+
+class WalletGatewayService
+{
+    public function __construct(
+        private WalletStatementRepository $walletStatementRepository,
+    ) {}
+
+    public function getAccountingBalance(Accounting $accounting): Money
+    {
+        $available = Brick\Money::ofMinor(0, $accounting->getCurrency());
+        $statements = $this->walletStatementRepository->findByAccounting($accounting);
+
+        foreach ($statements as $statement) {
+            $transaction = $statement->getTransaction();
+            $money = Brick\Money::ofMinor(
+                $transaction->getMoney()->amount,
+                $transaction->getMoney()->currency
+            );
+
+            switch ($statement->getDirection()) {
+                case WalletStatementDirection::Incoming:
+                    $available = $available->plus($money);
+                    break;
+                case WalletStatementDirection::Outgoing:
+                    $available = $available->minus($money);
+                    break;
+            }
+        }
+
+        return new Money(
+            $available->getMinorAmount()->toInt(),
+            $available->getCurrency()->getCurrencyCode()
+        );
+    }
+}