diff --git a/electrum/simple_config.py b/electrum/simple_config.py
index 9063f1a1c..e4d75dae4 100644
--- a/electrum/simple_config.py
+++ b/electrum/simple_config.py
@@ -321,8 +321,6 @@ class SimpleConfig(PrintError):
             depth += s
             if fee <= target_fee:
                 break
-        else:
-            return 0
         return depth
 
     def depth_to_fee(self, slider_pos) -> int:
@@ -333,7 +331,7 @@ class SimpleConfig(PrintError):
     @impose_hard_limits_on_fee
     def depth_target_to_fee(self, target: int) -> int:
         """Returns fee in sat/kbyte.
-        target: desired mempool depth in sat/vbyte
+        target: desired mempool depth in vbytes
         """
         depth = 0
         for fee, s in self.mempool_fees:
diff --git a/electrum/tests/test_simple_config.py b/electrum/tests/test_simple_config.py
index 14ea7baf0..6a3dbd023 100644
--- a/electrum/tests/test_simple_config.py
+++ b/electrum/tests/test_simple_config.py
@@ -111,7 +111,7 @@ class Test_SimpleConfig(SequentialTestCase):
         self.assertEqual({"something": "a"}, result)
 
     def test_depth_target_to_fee(self):
-        config = SimpleConfig({})
+        config = SimpleConfig(self.options)
         config.mempool_fees = [[49, 100110], [10, 121301], [6, 153731], [5, 125872], [1, 36488810]]
         self.assertEqual( 2 * 1000, config.depth_target_to_fee(1000000))
         self.assertEqual( 6 * 1000, config.depth_target_to_fee( 500000))
@@ -134,7 +134,7 @@ class Test_SimpleConfig(SequentialTestCase):
         self.assertEqual( 1 * 1000, config.depth_target_to_fee(10 ** 8))
 
     def test_fee_to_depth(self):
-        config = SimpleConfig({})
+        config = SimpleConfig(self.options)
         config.mempool_fees = [[49, 100000], [10, 120000], [6, 150000], [5, 125000], [1, 36000000]]
         self.assertEqual(100000, config.fee_to_depth(500))
         self.assertEqual(100000, config.fee_to_depth(50))
@@ -145,6 +145,7 @@ class Test_SimpleConfig(SequentialTestCase):
         self.assertEqual(370000, config.fee_to_depth(6.5))
         self.assertEqual(370000, config.fee_to_depth(6))
         self.assertEqual(495000, config.fee_to_depth(5.5))
+        self.assertEqual(36495000, config.fee_to_depth(0.5))
 
 
 class TestUserConfig(SequentialTestCase):