diff --git a/src/masternodes/undos.cpp b/src/masternodes/undos.cpp
index ba9f452e2a..ebc6176c52 100644
--- a/src/masternodes/undos.cpp
+++ b/src/masternodes/undos.cpp
@@ -7,24 +7,24 @@
 /// @attention make sure that it does not overlap with those in masternodes.cpp/tokens.cpp/undos.cpp/accounts.cpp !!!
 const unsigned char CUndosView::ByUndoKey::prefix = 'u';
 
-void CUndosView::ForEachUndo(std::function<bool(UndoKey, CLazySerialize<CUndo>)> callback, UndoKey const & start)
+void CUndosView::ForEachUndo(std::function<bool(UndoKey const &, CLazySerialize<CUndo>)> callback, UndoKey const & start)
 {
     ForEach<ByUndoKey, UndoKey, CUndo>(callback, start);
 }
 
-Res CUndosView::SetUndo(UndoKey key, CUndo const & undo)
+Res CUndosView::SetUndo(UndoKey const & key, CUndo const & undo)
 {
     WriteBy<ByUndoKey>(key, undo);
     return Res::Ok();
 }
 
-Res CUndosView::DelUndo(UndoKey key)
+Res CUndosView::DelUndo(UndoKey const & key)
 {
     EraseBy<ByUndoKey>(key);
     return Res::Ok();
 }
 
-boost::optional<CUndo> CUndosView::GetUndo(UndoKey key) const
+boost::optional<CUndo> CUndosView::GetUndo(UndoKey const & key) const
 {
     CUndo val;
     bool ok = ReadBy<ByUndoKey>(key, val);
diff --git a/src/masternodes/undos.h b/src/masternodes/undos.h
index 76b29908b9..2d215e8184 100644
--- a/src/masternodes/undos.h
+++ b/src/masternodes/undos.h
@@ -11,11 +11,11 @@
 
 class CUndosView : public virtual CStorageView {
 public:
-    void ForEachUndo(std::function<bool(UndoKey, CLazySerialize<CUndo>)> callback, UndoKey const & start = {});
+    void ForEachUndo(std::function<bool(UndoKey const &, CLazySerialize<CUndo>)> callback, UndoKey const & start = {});
 
-    boost::optional<CUndo> GetUndo(UndoKey key) const;
-    Res SetUndo(UndoKey key, CUndo const & undo);
-    Res DelUndo(UndoKey key);
+    boost::optional<CUndo> GetUndo(UndoKey const & key) const;
+    Res SetUndo(UndoKey const & key, CUndo const & undo);
+    Res DelUndo(UndoKey const & key);
 
     // tags
     struct ByUndoKey { static const unsigned char prefix; };
diff --git a/src/validation.cpp b/src/validation.cpp
index 3fd88d2d2c..cbfb6b041e 100644
--- a/src/validation.cpp
+++ b/src/validation.cpp
@@ -2419,6 +2419,22 @@ bool CChainState::ConnectBlock(const CBlock& block, CValidationState& state, CBl
     }
     mnview.SetLastHeight(pindex->nHeight);
 
+    if (fCheckpointsEnabled) {
+        auto &checkpoints = chainparams.Checkpoints().mapCheckpoints;
+        auto it = checkpoints.lower_bound(pindex->nHeight);
+        if (it != checkpoints.begin()) {
+            --it;
+            CCustomCSView pruned(mnview);
+            mnview.ForEachUndo([&](UndoKey const & key, CLazySerialize<CUndo>) {
+                if (key.height >= it->first) { // don't erase checkpoint height
+                    return false;
+                }
+                return pruned.DelUndo(key).ok;
+            });
+            pruned.Flush();
+        }
+    }
+
     int64_t nTime5 = GetTimeMicros(); nTimeIndex += nTime5 - nTime4;
     LogPrint(BCLog::BENCH, "    - Index writing: %.2fms [%.2fs (%.2fms/blk)]\n", MILLI * (nTime5 - nTime4), nTimeIndex * MICRO, nTimeIndex * MILLI / nBlocksTotal);
 
@@ -3007,7 +3023,7 @@ bool CChainState::ActivateBestChainStep(CValidationState& state, const CChainPar
                         InvalidChainFound(vpindexToConnect.front());
                     }
                     state = CValidationState();
-                    if (pindexConnect == pindexMostWork) {
+                    if (fCheckpointsEnabled && pindexConnect == pindexMostWork) {
                         // NOTE: Invalidate blocks back to last checkpoint
                         auto &checkpoints = chainparams.Checkpoints().mapCheckpoints;
                         auto it = checkpoints.lower_bound(pindexConnect->nHeight);