diff --git a/src/txmempool.cpp b/src/txmempool.cpp
index b4ec9bd6791..fcfc27d38ee 100644
--- a/src/txmempool.cpp
+++ b/src/txmempool.cpp
@@ -5,6 +5,7 @@
 
 #include <txmempool.h>
 
+#include <chain.h>
 #include <coins.h>
 #include <consensus/consensus.h>
 #include <consensus/tx_verify.h>
diff --git a/src/txmempool.h b/src/txmempool.h
index 6ba474e228b..f87ecc9cd08 100644
--- a/src/txmempool.h
+++ b/src/txmempool.h
@@ -14,7 +14,6 @@
 #include <utility>
 #include <vector>
 
-#include <chain.h>
 #include <coins.h>
 #include <consensus/amount.h>
 #include <indirectmap.h>
@@ -26,12 +25,13 @@
 #include <util/epochguard.h>
 #include <util/hasher.h>
 
-#include <boost/multi_index_container.hpp>
 #include <boost/multi_index/hashed_index.hpp>
 #include <boost/multi_index/ordered_index.hpp>
 #include <boost/multi_index/sequenced_index.hpp>
+#include <boost/multi_index_container.hpp>
 
 class CBlockIndex;
+class CChain;
 class CChainState;
 extern RecursiveMutex cs_main;