diff --git a/src/net_processing.cpp b/src/net_processing.cpp
--- a/src/net_processing.cpp
+++ b/src/net_processing.cpp
@@ -1187,10 +1187,11 @@
             // included in a block. As this is best effort, we only check for
             // output 0 and 1. This works well enough in practice and we get
             // diminishing returns with 2 onward.
+            const TxId txid(inv.hash);
             return recentRejects->contains(inv.hash) ||
                    g_mempool.exists(inv.hash) ||
-                   pcoinsTip->HaveCoinInCache(COutPoint(inv.hash, 0)) ||
-                   pcoinsTip->HaveCoinInCache(COutPoint(inv.hash, 1));
+                   pcoinsTip->HaveCoinInCache(COutPoint(txid, 0)) ||
+                   pcoinsTip->HaveCoinInCache(COutPoint(txid, 1));
         }
         case MSG_BLOCK:
             return LookupBlockIndex(inv.hash) != nullptr;
@@ -2477,8 +2478,9 @@
         bool fMissingInputs = false;
         CValidationState state;
 
-        pfrom->setAskFor.erase(inv.hash);
-        mapAlreadyAskedFor.erase(inv.hash);
+        const TxId txid(inv.hash);
+        pfrom->setAskFor.erase(txid);
+        mapAlreadyAskedFor.erase(txid);
 
         if (!AlreadyHave(inv) &&
             AcceptToMemoryPool(config, g_mempool, state, ptx, true,
@@ -2486,7 +2488,7 @@
             g_mempool.check(pcoinsTip.get());
             RelayTransaction(tx, connman);
             for (size_t i = 0; i < tx.vout.size(); i++) {
-                vWorkQueue.emplace_back(inv.hash, i);
+                vWorkQueue.emplace_back(txid, i);
             }
 
             pfrom->nLastTXTime = GetTime();
@@ -2511,7 +2513,7 @@
                      mi != itByPrev->second.end(); ++mi) {
                     const CTransactionRef &porphanTx = (*mi)->second.tx;
                     const CTransaction &orphanTx = *porphanTx;
-                    const uint256 &orphanId = orphanTx.GetId();
+                    const TxId &orphanId = orphanTx.GetId();
                     NodeId fromPeer = (*mi)->second.fromPeer;
                     bool fMissingInputs2 = false;
                     // Use a dummy CValidationState so someone can't setup nodes
diff --git a/src/primitives/transaction.h b/src/primitives/transaction.h
--- a/src/primitives/transaction.h
+++ b/src/primitives/transaction.h
@@ -26,7 +26,7 @@
 
 public:
     COutPoint() : txid(), n(-1) {}
-    COutPoint(uint256 txidIn, uint32_t nIn) : txid(TxId(txidIn)), n(nIn) {}
+    COutPoint(TxId txidIn, uint32_t nIn) : txid(txidIn), n(nIn) {}
 
     ADD_SERIALIZE_METHODS;
 
diff --git a/src/rest.cpp b/src/rest.cpp
--- a/src/rest.cpp
+++ b/src/rest.cpp
@@ -490,7 +490,6 @@
         }
 
         for (size_t i = (fCheckMemPool) ? 1 : 0; i < uriParts.size(); i++) {
-            uint256 txid;
             int32_t nOutput;
             std::string strTxid = uriParts[i].substr(0, uriParts[i].find("-"));
             std::string strOutput =
@@ -500,8 +499,9 @@
                 return RESTERR(req, HTTP_BAD_REQUEST, "Parse error");
             }
 
+            TxId txid;
             txid.SetHex(strTxid);
-            vOutPoints.push_back(COutPoint(txid, (uint32_t)nOutput));
+            vOutPoints.push_back(COutPoint(txid, uint32_t(nOutput)));
         }
 
         if (vOutPoints.size() > 0) {
diff --git a/src/rpc/blockchain.cpp b/src/rpc/blockchain.cpp
--- a/src/rpc/blockchain.cpp
+++ b/src/rpc/blockchain.cpp
@@ -1158,10 +1158,10 @@
 
     UniValue ret(UniValue::VOBJ);
 
-    std::string strHash = request.params[0].get_str();
-    uint256 hash(uint256S(strHash));
+    std::string strTxId = request.params[0].get_str();
+    TxId txid(uint256S(strTxId));
     int n = request.params[1].get_int();
-    COutPoint out(hash, n);
+    COutPoint out(txid, n);
     bool fMempool = true;
     if (!request.params[2].isNull()) {
         fMempool = request.params[2].get_bool();
diff --git a/src/rpc/rawtransaction.cpp b/src/rpc/rawtransaction.cpp
--- a/src/rpc/rawtransaction.cpp
+++ b/src/rpc/rawtransaction.cpp
@@ -485,7 +485,7 @@
         const UniValue &input = inputs[idx];
         const UniValue &o = input.get_obj();
 
-        uint256 txid = ParseHashO(o, "txid");
+        TxId txid(ParseHashO(o, "txid"));
 
         const UniValue &vout_v = find_value(o, "vout");
         if (vout_v.isNull()) {
@@ -868,7 +868,7 @@
                                 // (which are valid JSON)
                             });
 
-            uint256 txid = ParseHashO(prevOut, "txid");
+            TxId txid(ParseHashO(prevOut, "txid"));
 
             int nOut = find_value(prevOut, "vout").get_int();
             if (nOut < 0) {
@@ -1311,7 +1311,7 @@
     }
 
     CTransactionRef tx(MakeTransactionRef(std::move(mtx)));
-    const uint256 &txid = tx->GetId();
+    const TxId &txid = tx->GetId();
 
     Amount nMaxRawTxFee = maxTxFee;
     if (request.params.size() > 1 && request.params[1].get_bool()) {
diff --git a/src/test/coins_tests.cpp b/src/test/coins_tests.cpp
--- a/src/test/coins_tests.cpp
+++ b/src/test/coins_tests.cpp
@@ -143,7 +143,7 @@
         // Do a random modification.
         {
             // txid we're going to modify in this iteration.
-            TxId txid = txids[InsecureRandRange(txids.size())];
+            const TxId txid = txids[InsecureRandRange(txids.size())];
             Coin &coin = result[COutPoint(txid, 0)];
             // Determine whether to test HaveCoin before or after Access* (or
             // both). As these functions can influence each other's behaviour by
@@ -276,7 +276,7 @@
 
 UtxoData::iterator FindRandomFrom(const std::set<COutPoint> &utxoSet) {
     assert(utxoSet.size());
-    auto utxoSetIt = utxoSet.lower_bound(COutPoint(InsecureRand256(), 0));
+    auto utxoSetIt = utxoSet.lower_bound(COutPoint(TxId(InsecureRand256()), 0));
     if (utxoSetIt == utxoSet.end()) {
         utxoSetIt = utxoSet.begin();
     }
diff --git a/src/test/denialofservice_tests.cpp b/src/test/denialofservice_tests.cpp
--- a/src/test/denialofservice_tests.cpp
+++ b/src/test/denialofservice_tests.cpp
@@ -359,7 +359,7 @@
     for (int i = 0; i < 50; i++) {
         CMutableTransaction tx;
         tx.vin.resize(1);
-        tx.vin[0].prevout = COutPoint(InsecureRand256(), 0);
+        tx.vin[0].prevout = COutPoint(TxId(InsecureRand256()), 0);
         tx.vin[0].scriptSig << OP_1;
         tx.vout.resize(1);
         tx.vout[0].nValue = 1 * CENT;
diff --git a/src/test/sighash_tests.cpp b/src/test/sighash_tests.cpp
--- a/src/test/sighash_tests.cpp
+++ b/src/test/sighash_tests.cpp
@@ -107,7 +107,7 @@
     for (int in = 0; in < ins; in++) {
         tx.vin.push_back(CTxIn());
         CTxIn &txin = tx.vin.back();
-        txin.prevout = COutPoint(InsecureRand256(), InsecureRandBits(2));
+        txin.prevout = COutPoint(TxId(InsecureRand256()), InsecureRandBits(2));
         RandomScript(txin.scriptSig);
         txin.nSequence = InsecureRandBool()
                              ? InsecureRand32()
diff --git a/src/test/sigopcount_tests.cpp b/src/test/sigopcount_tests.cpp
--- a/src/test/sigopcount_tests.cpp
+++ b/src/test/sigopcount_tests.cpp
@@ -256,7 +256,7 @@
     CMutableTransaction tx;
     tx.nVersion = 1;
     tx.vin.resize(1);
-    tx.vin[0].prevout = COutPoint(InsecureRand256(), 0);
+    tx.vin[0].prevout = COutPoint(TxId(InsecureRand256()), 0);
     tx.vin[0].scriptSig = CScript();
     tx.vout.resize(1);
     tx.vout[0].nValue = SATOSHI;
diff --git a/src/test/undo_tests.cpp b/src/test/undo_tests.cpp
--- a/src/test/undo_tests.cpp
+++ b/src/test/undo_tests.cpp
@@ -39,7 +39,7 @@
     ApplyBlockUndo(blockUndo, block, &pindex, view);
 }
 
-static bool HasSpendableCoin(const CCoinsViewCache &view, const uint256 &txid) {
+static bool HasSpendableCoin(const CCoinsViewCache &view, const TxId &txid) {
     return !view.AccessCoin(COutPoint(txid, 0)).IsSpent();
 }
 
@@ -67,7 +67,7 @@
     block.vtx[0] = MakeTransactionRef(tx);
 
     tx.vout[0].scriptPubKey = CScript() << OP_TRUE;
-    tx.vin[0].prevout = COutPoint(InsecureRand256(), 0);
+    tx.vin[0].prevout = COutPoint(TxId(InsecureRand256()), 0);
     tx.vin[0].nSequence = CTxIn::SEQUENCE_FINAL;
     tx.vin[0].scriptSig.resize(0);
     tx.nVersion = 2;
diff --git a/src/test/validation_block_tests.cpp b/src/test/validation_block_tests.cpp
--- a/src/test/validation_block_tests.cpp
+++ b/src/test/validation_block_tests.cpp
@@ -92,7 +92,7 @@
 
     CMutableTransaction coinbase_spend;
     coinbase_spend.vin.push_back(
-        CTxIn(COutPoint(pblock->vtx[0]->GetHash(), 0), CScript(), 0));
+        CTxIn(COutPoint(pblock->vtx[0]->GetId(), 0), CScript(), 0));
     coinbase_spend.vout.push_back(pblock->vtx[0]->vout[0]);
 
     CTransactionRef tx = MakeTransactionRef(coinbase_spend);
diff --git a/src/txdb.cpp b/src/txdb.cpp
--- a/src/txdb.cpp
+++ b/src/txdb.cpp
@@ -46,7 +46,7 @@
 
     template <typename Stream> void Unserialize(Stream &s) {
         s >> key;
-        uint256 id;
+        TxId id;
         s >> id;
         uint32_t n = 0;
         s >> VARINT(n);