diff --git a/src/wallet/test/wallet_tests.cpp b/src/wallet/test/wallet_tests.cpp
--- a/src/wallet/test/wallet_tests.cpp
+++ b/src/wallet/test/wallet_tests.cpp
@@ -781,18 +781,24 @@
     BOOST_CHECK_EQUAL(list.begin()->second.size(), 2);
 
     // Lock both coins. Confirm number of available coins drops to 0.
-    std::vector<COutput> available;
-    wallet->AvailableCoins(available);
-    BOOST_CHECK_EQUAL(available.size(), 2);
+    {
+        LOCK2(cs_main, wallet->cs_wallet);
+        std::vector<COutput> available;
+        wallet->AvailableCoins(available);
+        BOOST_CHECK_EQUAL(available.size(), 2);
+    }
     for (const auto &group : list) {
         for (const auto &coin : group.second) {
             LOCK(wallet->cs_wallet);
             wallet->LockCoin(COutPoint(coin.tx->GetId(), coin.i));
         }
     }
-    wallet->AvailableCoins(available);
-    BOOST_CHECK_EQUAL(available.size(), 0);
-
+    {
+        LOCK2(cs_main, wallet->cs_wallet);
+        std::vector<COutput> available;
+        wallet->AvailableCoins(available);
+        BOOST_CHECK_EQUAL(available.size(), 0);
+    }
     // Confirm ListCoins still returns same result as before, despite coins
     // being locked.
     list = wallet->ListCoins();
diff --git a/src/wallet/wallet.cpp b/src/wallet/wallet.cpp
--- a/src/wallet/wallet.cpp
+++ b/src/wallet/wallet.cpp
@@ -2331,10 +2331,12 @@
                              const Amount nMinimumSumAmount,
                              const uint64_t nMaximumCount, const int nMinDepth,
                              const int nMaxDepth) const {
+    AssertLockHeld(cs_main);
+    AssertLockHeld(cs_wallet);
+
     vCoins.clear();
     Amount nTotal = Amount::zero();
 
-    LOCK2(cs_main, cs_wallet);
     for (const auto &entry : mapWallet) {
         const TxId &wtxid = entry.first;
         const CWalletTx *pcoin = &entry.second;
@@ -2454,11 +2456,11 @@
     // avoid adding some extra complexity to the Qt code.
 
     std::map<CTxDestination, std::vector<COutput>> result;
-
     std::vector<COutput> availableCoins;
-    AvailableCoins(availableCoins);
 
     LOCK2(cs_main, cs_wallet);
+    AvailableCoins(availableCoins);
+
     for (auto &coin : availableCoins) {
         CTxDestination address;
         if (coin.fSpendable &&