diff --git a/freqtrade/exchange/exchange.py b/freqtrade/exchange/exchange.py
index 7c983e58e..6689731d8 100644
--- a/freqtrade/exchange/exchange.py
+++ b/freqtrade/exchange/exchange.py
@@ -75,7 +75,7 @@ class Exchange:
     }
     _ft_has: Dict = {}
 
-    _leverage_brackets: Dict
+    _leverage_brackets: Dict = {}
 
     def __init__(self, config: Dict[str, Any], validate: bool = True) -> None:
         """
diff --git a/tests/exchange/test_ftx.py b/tests/exchange/test_ftx.py
index 8b44b6069..0f3870a7f 100644
--- a/tests/exchange/test_ftx.py
+++ b/tests/exchange/test_ftx.py
@@ -195,6 +195,12 @@ def test_get_order_id(mocker, default_conf):
     assert exchange.get_order_id_conditional(order) == '1111'
 
 
+def test_fill_leverage_brackets(default_conf, mocker):
+    exchange = get_patched_exchange(mocker, default_conf, id="ftx")
+    exchange.fill_leverage_brackets()
+    assert bool(exchange._leverage_brackets) is False
+
+
 @pytest.mark.parametrize('pair,nominal_value,max_lev', [
     ("ADA/BTC", 0.0, 20.0),
     ("BTC/EUR", 100.0, 20.0),