diff --git a/src/lhmask.js b/src/lhmask.js
index 228fbac..85b5b06 100644
--- a/src/lhmask.js
+++ b/src/lhmask.js
@@ -68,7 +68,7 @@ function formatarCpfCnpj(txt) {
 
 // Entrada: 12345 Saída: 1234-5
 function formatarContaBancaria(txt) {
-    const soNumeros = `${txt}`.replace(/[^\d]/g, '')
+    const soNumeros = `${txt}`.replace(/[^\dxX]/g, '')
     if (!soNumeros) return soNumeros;
 
     let conta = '';
diff --git a/src/lhmask.test.js b/src/lhmask.test.js
index c594f29..f88af28 100644
--- a/src/lhmask.test.js
+++ b/src/lhmask.test.js
@@ -22,7 +22,11 @@ const testes = {
     },
     'contabancaria': {
         'fnName': "formatarContaBancaria",
-        'valores': [['1234-5', '1234-5']]
+        'valores': [
+            ['12345', '1234-5'],
+            ['12345x', '12345-x'],
+            ['12345X', '12345-X']
+        ]
     },
     'telefone': {
         'fnName': 'formatarTelefone',