diff --git a/beacon_node/beacon_chain/src/beacon_chain.rs b/beacon_node/beacon_chain/src/beacon_chain.rs
index 77011a6d5..944079aa0 100644
--- a/beacon_node/beacon_chain/src/beacon_chain.rs
+++ b/beacon_node/beacon_chain/src/beacon_chain.rs
@@ -672,6 +672,8 @@ impl<T: BeaconChainTypes> BeaconChain<T> {
             }
         }
 
+        state.build_committee_cache(RelativeEpoch::Current, &T::EthSpec::spec())?;
+
         // Apply the received block to its parent state (which has been transitioned into this
         // slot).
         if let Err(e) = per_block_processing(&mut state, &block, &T::EthSpec::spec()) {