diff --git a/electrum/fee_policy.py b/electrum/fee_policy.py
index dd42237b0..cfb1909c4 100644
--- a/electrum/fee_policy.py
+++ b/electrum/fee_policy.py
@@ -64,8 +64,10 @@ class FeeMethod(IntEnum):
 
     @classmethod
     def slider_index_of_method(cls, method):
-        i = FeeMethod.slider_values().index(method)
-        assert i is not None
+        try:
+            i = FeeMethod.slider_values().index(method)
+        except ValueError:
+            i = -1
         return i
 
 
diff --git a/electrum/gui/qt/confirm_tx_dialog.py b/electrum/gui/qt/confirm_tx_dialog.py
index 798be1b56..0babb0ef1 100644
--- a/electrum/gui/qt/confirm_tx_dialog.py
+++ b/electrum/gui/qt/confirm_tx_dialog.py
@@ -38,7 +38,7 @@ from electrum.plugin import run_hook
 from electrum.transaction import Transaction, PartialTransaction
 from electrum.wallet import InternalAddressCorruption
 from electrum.bitcoin import DummyAddress
-from electrum.fee_policy import FeePolicy, FixedFeePolicy
+from electrum.fee_policy import FeePolicy, FixedFeePolicy, FeeMethod
 
 from .util import (WindowModalDialog, ColorScheme, HelpLabel, Buttons, CancelButton,
                    WWLabel, read_QIcon)
@@ -163,7 +163,6 @@ class TxEditor(WindowModalDialog):
         self.fiat_fee_label.setStyleSheet(ColorScheme.DEFAULT.as_stylesheet())
 
         self.feerate_e = FeerateEdit(lambda: 0)
-        self.feerate_e.setAmount(self.fee_policy.fee_per_byte(self.network))
         self.feerate_e.textEdited.connect(partial(self.on_fee_or_feerate, self.feerate_e, False))
         self.feerate_e.editingFinished.connect(partial(self.on_fee_or_feerate, self.feerate_e, True))
         self.update_feerate_label()
@@ -175,6 +174,11 @@ class TxEditor(WindowModalDialog):
         self.feerate_e.setFixedWidth(150)
         self.fee_e.setFixedWidth(150)
 
+        if self.fee_policy.method != FeeMethod.FIXED:
+            self.feerate_e.setAmount(self.fee_policy.fee_per_byte(self.network))
+        else:
+            self.fee_e.setAmount(self.fee_policy.value)
+
         self.fee_e.textChanged.connect(self.entry_changed)
         self.feerate_e.textChanged.connect(self.entry_changed)
 
@@ -229,6 +233,8 @@ class TxEditor(WindowModalDialog):
         self.needs_update = True
 
     def fee_slider_callback(self, fee_rate):
+        if self.fee_policy.method == FeeMethod.FIXED:
+            return
         self.config.FEE_POLICY = self.fee_policy.get_descriptor()
         self.fee_slider.activate()
         if fee_rate:
diff --git a/electrum/gui/qt/fee_slider.py b/electrum/gui/qt/fee_slider.py
index 1f407f233..79a76439f 100644
--- a/electrum/gui/qt/fee_slider.py
+++ b/electrum/gui/qt/fee_slider.py
@@ -60,6 +60,8 @@ class FeeSlider(QSlider):
 
     def moved(self, pos):
         with self.lock:
+            if self.fee_policy.method == FeeMethod.FIXED:
+                return
             self.fee_policy.set_value_from_slider_pos(pos)
             fee_rate = self.fee_policy.fee_per_kb(self.network)
             tooltip = self.fee_policy.get_tooltip(self.network)
@@ -69,6 +71,8 @@ class FeeSlider(QSlider):
 
     def update(self, *, is_initialized: bool = True):
         with self.lock:
+            if self.fee_policy.method == FeeMethod.FIXED:
+                return
             pos = self.fee_policy.get_slider_pos()
             maxp = self.fee_policy.get_slider_max()
             self.setRange(0, maxp)