diff --git a/common/eth2_network_config/built_in_network_configs/gnosis/config.yaml b/common/eth2_network_config/built_in_network_configs/gnosis/config.yaml
index 12d799528..d762ecfbd 100644
--- a/common/eth2_network_config/built_in_network_configs/gnosis/config.yaml
+++ b/common/eth2_network_config/built_in_network_configs/gnosis/config.yaml
@@ -74,9 +74,8 @@ CHURN_LIMIT_QUOTIENT: 4096
 
 # Fork choice
 # ---------------------------------------------------------------
-# TODO: enable once proposer boosting is desired on mainnet
 # 70%
-# PROPOSER_SCORE_BOOST: 70
+PROPOSER_SCORE_BOOST: 70
 
 # Deposit contract
 # ---------------------------------------------------------------
diff --git a/common/eth2_network_config/built_in_network_configs/mainnet/config.yaml b/common/eth2_network_config/built_in_network_configs/mainnet/config.yaml
index 6993c24b8..16aa507ee 100644
--- a/common/eth2_network_config/built_in_network_configs/mainnet/config.yaml
+++ b/common/eth2_network_config/built_in_network_configs/mainnet/config.yaml
@@ -74,9 +74,8 @@ CHURN_LIMIT_QUOTIENT: 65536
 
 # Fork choice
 # ---------------------------------------------------------------
-# TODO: enable once proposer boosting is desired on mainnet
 # 70%
-# PROPOSER_SCORE_BOOST: 70
+PROPOSER_SCORE_BOOST: 70
 
 # Deposit contract
 # ---------------------------------------------------------------
diff --git a/consensus/types/src/chain_spec.rs b/consensus/types/src/chain_spec.rs
index cd6e90645..eb081f3ec 100644
--- a/consensus/types/src/chain_spec.rs
+++ b/consensus/types/src/chain_spec.rs
@@ -500,7 +500,7 @@ impl ChainSpec {
              * Fork choice
              */
             safe_slots_to_update_justified: 8,
-            proposer_score_boost: None,
+            proposer_score_boost: Some(70),
 
             /*
              * Eth1
@@ -698,7 +698,7 @@ impl ChainSpec {
              * Fork choice
              */
             safe_slots_to_update_justified: 8,
-            proposer_score_boost: None,
+            proposer_score_boost: Some(70),
 
             /*
              * Eth1