diff --git a/electrum/lnchannel.py b/electrum/lnchannel.py
index fecc5a191236..dd08135daa08 100644
--- a/electrum/lnchannel.py
+++ b/electrum/lnchannel.py
@@ -61,6 +61,7 @@
 from .lnutil import CHANNEL_OPENING_TIMEOUT
 from .lnutil import ChannelBackupStorage, ImportedChannelBackupStorage, OnchainChannelBackupStorage
 from .lnutil import format_short_channel_id
+from .simple_config import FEERATE_PER_KW_MIN_RELAY_LIGHTNING
 
 if TYPE_CHECKING:
     from .lnworker import LNWallet
@@ -1346,6 +1347,8 @@ def update_fee(self, feerate: int, from_us: bool) -> None:
         # feerate uses sat/kw
         if self.constraints.is_initiator != from_us:
             raise Exception(f"Cannot update_fee: wrong initiator. us: {from_us}")
+        if feerate < FEERATE_PER_KW_MIN_RELAY_LIGHTNING:
+            raise Exception(f"Cannot update_fee: feerate lower than min relay fee. {feerate} sat/kw. us: {from_us}")
         sender = LOCAL if from_us else REMOTE
         ctx_owner = -sender
         ctn = self.get_next_ctn(ctx_owner)
diff --git a/electrum/lnutil.py b/electrum/lnutil.py
index 7cc1bfb5e756..2e3441c9a5e1 100644
--- a/electrum/lnutil.py
+++ b/electrum/lnutil.py
@@ -169,6 +169,9 @@ def cross_validate_params(
             raise Exception(
                 "both to_local and to_remote amounts for the initial commitment "
                 "transaction are less than or equal to channel_reserve_satoshis")
+        from .simple_config import FEERATE_PER_KW_MIN_RELAY_LIGHTNING
+        if initial_feerate_per_kw < FEERATE_PER_KW_MIN_RELAY_LIGHTNING:
+            raise Exception(f"feerate lower than min relay fee. {initial_feerate_per_kw} sat/kw.")
 
 
 @attr.s
diff --git a/electrum/lnworker.py b/electrum/lnworker.py
index 41771a48809c..7a60bd885278 100644
--- a/electrum/lnworker.py
+++ b/electrum/lnworker.py
@@ -2096,12 +2096,13 @@ async def reestablish_peers_and_channels(self):
 
     def current_feerate_per_kw(self):
         from .simple_config import FEE_LN_ETA_TARGET, FEERATE_FALLBACK_STATIC_FEE, FEERATE_REGTEST_HARDCODED
+        from .simple_config import FEERATE_PER_KW_MIN_RELAY_LIGHTNING
         if constants.net is constants.BitcoinRegtest:
             return FEERATE_REGTEST_HARDCODED // 4
         feerate_per_kvbyte = self.network.config.eta_target_to_fee(FEE_LN_ETA_TARGET)
         if feerate_per_kvbyte is None:
             feerate_per_kvbyte = FEERATE_FALLBACK_STATIC_FEE
-        return max(253, feerate_per_kvbyte // 4)
+        return max(FEERATE_PER_KW_MIN_RELAY_LIGHTNING, feerate_per_kvbyte // 4)
 
     def create_channel_backup(self, channel_id):
         chan = self._channels[channel_id]
diff --git a/electrum/simple_config.py b/electrum/simple_config.py
index 2c207db07796..8320b63f4063 100644
--- a/electrum/simple_config.py
+++ b/electrum/simple_config.py
@@ -34,6 +34,12 @@
                          50000, 70000, 100000, 150000, 200000, 300000]
 FEERATE_REGTEST_HARDCODED = 180000  # for eclair compat
 
+# The min feerate_per_kw that can be used in lightning so that
+# the resulting onchain tx pays the min relay fee.
+# This would be FEERATE_DEFAULT_RELAY / 4 if not for rounding errors,
+# see https://github.com/ElementsProject/lightning/commit/2e687b9b352c9092b5e8bd4a688916ac50b44af0
+FEERATE_PER_KW_MIN_RELAY_LIGHTNING = 253
+
 FEE_RATIO_HIGH_WARNING = 0.05  # warn user if fee/amount for on-chain tx is higher than this
 
 
diff --git a/electrum/tests/test_lnchannel.py b/electrum/tests/test_lnchannel.py
index 0d1373073b27..eb6230e4ee13 100644
--- a/electrum/tests/test_lnchannel.py
+++ b/electrum/tests/test_lnchannel.py
@@ -532,7 +532,7 @@ def test_SimpleAddSettleWorkflow(self):
         self.assertEqual(bob_channel.total_msat(SENT), 5 * one_bitcoin_in_msat, "bob satoshis sent incorrect")
 
 
-    def alice_to_bob_fee_update(self, fee=111):
+    def alice_to_bob_fee_update(self, fee=1111):
         aoldctx = self.alice_channel.get_next_commitment(REMOTE).outputs()
         self.alice_channel.update_fee(fee, True)
         anewctx = self.alice_channel.get_next_commitment(REMOTE).outputs()