diff --git a/freqtrade/exchange/exchange.py b/freqtrade/exchange/exchange.py
index af3e4c3eb..e0da0878d 100644
--- a/freqtrade/exchange/exchange.py
+++ b/freqtrade/exchange/exchange.py
@@ -651,7 +651,7 @@ class Exchange:
         Re-implementation of ccxt internal methods - ensuring we can test the result is correct
         based on our definitions.
         """
-        if self.markets[pair]['precision']['amount']:
+        if self.markets[pair]['precision']['amount'] is not None:
             amount = float(decimal_to_precision(amount, rounding_mode=TRUNCATE,
                                                 precision=self.markets[pair]['precision']['amount'],
                                                 counting_mode=self.precisionMode,
diff --git a/tests/exchange/test_exchange.py b/tests/exchange/test_exchange.py
index cffeec5b3..e99121489 100644
--- a/tests/exchange/test_exchange.py
+++ b/tests/exchange/test_exchange.py
@@ -231,6 +231,10 @@ def test_validate_order_time_in_force(default_conf, mocker, caplog):
     (2.34559, 2, 3, 1, 2.345, 'spot'),
     (2.9999, 2, 3, 1, 2.999, 'spot'),
     (2.9909, 2, 3, 1, 2.990, 'spot'),
+    (2.9909, 2, 0, 1, 2, 'spot'),
+    (29991.5555, 2, 0, 1, 29991, 'spot'),
+    (29991.5555, 2, -1, 1, 29990, 'spot'),
+    (29991.5555, 2, -2, 1, 29900, 'spot'),
     # Tests for Tick-size
     (2.34559, 4, 0.0001, 1, 2.3455, 'spot'),
     (2.34559, 4, 0.00001, 1, 2.34559, 'spot'),