diff --git a/src/test/blockencodings_tests.cpp b/src/test/blockencodings_tests.cpp
--- a/src/test/blockencodings_tests.cpp
+++ b/src/test/blockencodings_tests.cpp
@@ -108,7 +108,7 @@
             SHARED_TX_OFFSET + 1);
 
         size_t poolSize = pool.size();
-        pool.removeRecursive(*block.vtx[2]);
+        pool.removeRecursive(*block.vtx[2], MemPoolRemovalReason::REPLACED);
         BOOST_CHECK_EQUAL(pool.size(), poolSize - 1);
 
         CBlock block2;
diff --git a/src/test/mempool_tests.cpp b/src/test/mempool_tests.cpp
--- a/src/test/mempool_tests.cpp
+++ b/src/test/mempool_tests.cpp
@@ -182,6 +182,8 @@
     }
 }
 
+static constexpr auto REMOVAL_REASON_DUMMY = MemPoolRemovalReason::REPLACED;
+
 BOOST_AUTO_TEST_CASE(MempoolRemoveTest) {
     // Test CTxMemPool::remove functionality
 
@@ -219,13 +221,13 @@
 
     // Nothing in pool, remove should do nothing:
     unsigned int poolSize = testPool.size();
-    testPool.removeRecursive(CTransaction(txParent));
+    testPool.removeRecursive(CTransaction(txParent), REMOVAL_REASON_DUMMY);
     BOOST_CHECK_EQUAL(testPool.size(), poolSize);
 
     // Just the parent:
     testPool.addUnchecked(entry.FromTx(txParent));
     poolSize = testPool.size();
-    testPool.removeRecursive(CTransaction(txParent));
+    testPool.removeRecursive(CTransaction(txParent), REMOVAL_REASON_DUMMY);
     BOOST_CHECK_EQUAL(testPool.size(), poolSize - 1);
 
     // Parent, children, grandchildren:
@@ -236,18 +238,19 @@
     }
     // Remove Child[0], GrandChild[0] should be removed:
     poolSize = testPool.size();
-    testPool.removeRecursive(CTransaction(txChild[0]));
+    testPool.removeRecursive(CTransaction(txChild[0]), REMOVAL_REASON_DUMMY);
     BOOST_CHECK_EQUAL(testPool.size(), poolSize - 2);
     // ... make sure grandchild and child are gone:
     poolSize = testPool.size();
-    testPool.removeRecursive(CTransaction(txGrandChild[0]));
+    testPool.removeRecursive(CTransaction(txGrandChild[0]),
+                             REMOVAL_REASON_DUMMY);
     BOOST_CHECK_EQUAL(testPool.size(), poolSize);
     poolSize = testPool.size();
-    testPool.removeRecursive(CTransaction(txChild[0]));
+    testPool.removeRecursive(CTransaction(txChild[0]), REMOVAL_REASON_DUMMY);
     BOOST_CHECK_EQUAL(testPool.size(), poolSize);
     // Remove parent, all children/grandchildren should go:
     poolSize = testPool.size();
-    testPool.removeRecursive(CTransaction(txParent));
+    testPool.removeRecursive(CTransaction(txParent), REMOVAL_REASON_DUMMY);
     BOOST_CHECK_EQUAL(testPool.size(), poolSize - 5);
     BOOST_CHECK_EQUAL(testPool.size(), 0UL);
 
@@ -261,7 +264,7 @@
     // Now remove the parent, as might happen if a block-re-org occurs but the
     // parent cannot be put into the mempool (maybe because it is non-standard):
     poolSize = testPool.size();
-    testPool.removeRecursive(CTransaction(txParent));
+    testPool.removeRecursive(CTransaction(txParent), REMOVAL_REASON_DUMMY);
     BOOST_CHECK_EQUAL(testPool.size(), poolSize - 6);
     BOOST_CHECK_EQUAL(testPool.size(), 0UL);
 }
@@ -503,11 +506,14 @@
     BOOST_CHECK_EQUAL(pool.size(), 10UL);
 
     // Now try removing tx10 and verify the sort order returns to normal
-    pool.removeRecursive(pool.mapTx.find(tx10.GetId())->GetTx());
+    pool.removeRecursive(pool.mapTx.find(tx10.GetId())->GetTx(),
+                         REMOVAL_REASON_DUMMY);
     CheckSort<descendant_score>(pool, snapshotOrder, "MempoolIndexingTest7");
 
-    pool.removeRecursive(pool.mapTx.find(tx9.GetId())->GetTx());
-    pool.removeRecursive(pool.mapTx.find(tx8.GetId())->GetTx());
+    pool.removeRecursive(pool.mapTx.find(tx9.GetId())->GetTx(),
+                         REMOVAL_REASON_DUMMY);
+    pool.removeRecursive(pool.mapTx.find(tx8.GetId())->GetTx(),
+                         REMOVAL_REASON_DUMMY);
 }
 
 BOOST_AUTO_TEST_CASE(MempoolAncestorIndexingTest) {
diff --git a/src/test/miner_tests.cpp b/src/test/miner_tests.cpp
--- a/src/test/miner_tests.cpp
+++ b/src/test/miner_tests.cpp
@@ -185,7 +185,8 @@
     // Test that packages above the min relay fee do get included, even if one
     // of the transactions is below the min relay fee. Remove the low fee
     // transaction and replace with a higher fee transaction
-    m_node.mempool->removeRecursive(CTransaction(tx));
+    m_node.mempool->removeRecursive(CTransaction(tx),
+                                    MemPoolRemovalReason::REPLACED);
     // Now we should be just over the min relay fee.
     tx.vout[0].nValue -= 2 * SATOSHI;
     lowFeeTxId = tx.GetId();
diff --git a/src/txmempool.h b/src/txmempool.h
--- a/src/txmempool.h
+++ b/src/txmempool.h
@@ -369,8 +369,6 @@
  * notification signal.
  */
 enum class MemPoolRemovalReason {
-    //! Manually removed or unknown reason
-    UNKNOWN = 0,
     //! Expired from mempool
     EXPIRY,
     //! Removed in size limiting
@@ -627,9 +625,7 @@
     void addUnchecked(const CTxMemPoolEntry &entry, setEntries &setAncestors)
         EXCLUSIVE_LOCKS_REQUIRED(cs, cs_main);
 
-    void removeRecursive(
-        const CTransaction &tx,
-        MemPoolRemovalReason reason = MemPoolRemovalReason::UNKNOWN);
+    void removeRecursive(const CTransaction &tx, MemPoolRemovalReason reason);
     void removeForReorg(const Config &config, const CCoinsViewCache *pcoins,
                         unsigned int nMemPoolHeight, int flags)
         EXCLUSIVE_LOCKS_REQUIRED(cs_main);
@@ -679,10 +675,8 @@
      * updateDescendants to true when removing a tx that was in a block, so that
      * any in-mempool descendants have their ancestor state updated.
      */
-    void
-    RemoveStaged(setEntries &stage, bool updateDescendants,
-                 MemPoolRemovalReason reason = MemPoolRemovalReason::UNKNOWN)
-        EXCLUSIVE_LOCKS_REQUIRED(cs);
+    void RemoveStaged(setEntries &stage, bool updateDescendants,
+                      MemPoolRemovalReason reason) EXCLUSIVE_LOCKS_REQUIRED(cs);
 
     /**
      * When adding transactions from a disconnected block back to the mempool,
@@ -838,9 +832,7 @@
      * transaction that is removed, so we can't remove intermediate transactions
      * in a chain before we've updated all the state for the removal.
      */
-    void
-    removeUnchecked(txiter entry,
-                    MemPoolRemovalReason reason = MemPoolRemovalReason::UNKNOWN)
+    void removeUnchecked(txiter entry, MemPoolRemovalReason reason)
         EXCLUSIVE_LOCKS_REQUIRED(cs);
 };