diff --git a/core/genesis.go b/core/genesis.go
index 86a3e42a62..2220f8a192 100644
--- a/core/genesis.go
+++ b/core/genesis.go
@@ -367,7 +367,6 @@ func SetupGenesisBlockWithOverride(db ethdb.Database, triedb *trie.Database, gen
 		rawdb.WriteChainConfig(db, stored, newcfg)
 		return newcfg, stored, nil
 	}
-	storedData, _ := json.Marshal(storedcfg)
 	// Special case: if a private network is being used (no genesis and also no
 	// mainnet hash in the database), we must not apply the `configOrDefault`
 	// chain config as that would be AllProtocolChanges (applying any new fork
@@ -387,10 +386,7 @@ func SetupGenesisBlockWithOverride(db ethdb.Database, triedb *trie.Database, gen
 	if compatErr != nil && ((head.Number.Uint64() != 0 && compatErr.RewindToBlock != 0) || (head.Time != 0 && compatErr.RewindToTime != 0)) {
 		return newcfg, stored, compatErr
 	}
-	// Don't overwrite if the old is identical to the new
-	if newData, _ := json.Marshal(newcfg); !bytes.Equal(storedData, newData) {
-		rawdb.WriteChainConfig(db, stored, newcfg)
-	}
+	rawdb.WriteChainConfig(db, stored, newcfg)
 	return newcfg, stored, nil
 }