diff --git a/polkadot/runtime/kusama/src/lib.rs b/polkadot/runtime/kusama/src/lib.rs
index 512c55dd04..f9e23ed243 100644
--- a/polkadot/runtime/kusama/src/lib.rs
+++ b/polkadot/runtime/kusama/src/lib.rs
@@ -612,10 +612,6 @@ impl pallet_offences::Config for Runtime {
 
 impl pallet_authority_discovery::Config for Runtime {}
 
-parameter_types! {
-	pub const SessionDuration: BlockNumber = EPOCH_DURATION_IN_BLOCKS as _;
-}
-
 parameter_types! {
 	pub NposSolutionPriority: TransactionPriority =
 		Perbill::from_percent(90) * TransactionPriority::max_value();
diff --git a/polkadot/runtime/polkadot/src/lib.rs b/polkadot/runtime/polkadot/src/lib.rs
index 4bb5691dab..d8ee259cac 100644
--- a/polkadot/runtime/polkadot/src/lib.rs
+++ b/polkadot/runtime/polkadot/src/lib.rs
@@ -658,10 +658,6 @@ impl pallet_offences::Config for Runtime {
 
 impl pallet_authority_discovery::Config for Runtime {}
 
-parameter_types! {
-	pub const SessionDuration: BlockNumber = EPOCH_DURATION_IN_BLOCKS as _;
-}
-
 parameter_types! {
 	pub NposSolutionPriority: TransactionPriority =
 		Perbill::from_percent(90) * TransactionPriority::max_value();
diff --git a/polkadot/runtime/westend/src/lib.rs b/polkadot/runtime/westend/src/lib.rs
index 61ebf8dc0d..6037df1227 100644
--- a/polkadot/runtime/westend/src/lib.rs
+++ b/polkadot/runtime/westend/src/lib.rs
@@ -409,10 +409,6 @@ impl pallet_offences::Config for Runtime {
 
 impl pallet_authority_discovery::Config for Runtime {}
 
-parameter_types! {
-	pub const SessionDuration: BlockNumber = EPOCH_DURATION_IN_BLOCKS as _;
-}
-
 parameter_types! {
 	pub const NposSolutionPriority: TransactionPriority = TransactionPriority::max_value() / 2;
 	pub const ImOnlineUnsignedPriority: TransactionPriority = TransactionPriority::max_value();