diff --git a/freqtrade/exchange/exchange.py b/freqtrade/exchange/exchange.py
index 7ef0d7750..4acee710a 100644
--- a/freqtrade/exchange/exchange.py
+++ b/freqtrade/exchange/exchange.py
@@ -1104,9 +1104,12 @@ class Exchange:
                 order['fee']['cost'] / safe_value_fallback(order, order, 'filled', 'amount'), 8)
         elif fee_curr in self.get_pair_quote_currency(order['symbol']):
             # Quote currency - divide by cost
-            return round(order['fee']['cost'] / order['cost'], 8)
+            return round(order['fee']['cost'] / order['cost'], 8) if order['cost'] else None
         else:
             # If Fee currency is a different currency
+            if not order['cost']:
+                # If cost is None or 0.0 -> falsy, return None
+                return None
             try:
                 comb = self.get_valid_pair_combination(fee_curr, self._config['stake_currency'])
                 tick = self.fetch_ticker(comb)