diff --git a/src/libxrpl/ledger/helpers/LendingHelpers.cpp b/src/libxrpl/ledger/helpers/LendingHelpers.cpp
index 61ad7d8dbb..67a0f88e7a 100644
--- a/src/libxrpl/ledger/helpers/LendingHelpers.cpp
+++ b/src/libxrpl/ledger/helpers/LendingHelpers.cpp
@@ -39,10 +39,15 @@ canApplyToBrokerCover(
     beast::Journal j,
     std::string_view logPrefix)
 {
+    XRPL_ASSERT(
+        sleBroker && sleBroker->getType() == ltLOAN_BROKER,
+        "xrpl::canApplyToBrokerCover : valid LoanBroker sle");
+    XRPL_ASSERT(
+        vaultAsset.getIssuer() == amount.getIssuer() && amount > beast::kZERO,
+        "xrpl::canApplyToBrokerCover : valid LoanBroker sle");
+
     if (!view.rules().enabled(fixCleanup3_2_0))
         return tesSUCCESS;
-    if (amount == beast::kZERO)
-        return tesSUCCESS;
 
     int const coverScale = scale(sleBroker->at(sfCoverAvailable), vaultAsset);
     if (amount.isZeroAtScale(coverScale))
diff --git a/src/libxrpl/tx/transactors/lending/LoanBrokerCoverDeposit.cpp b/src/libxrpl/tx/transactors/lending/LoanBrokerCoverDeposit.cpp
index 010830dacb..2c46ca3ffb 100644
--- a/src/libxrpl/tx/transactors/lending/LoanBrokerCoverDeposit.cpp
+++ b/src/libxrpl/tx/transactors/lending/LoanBrokerCoverDeposit.cpp
@@ -73,11 +73,6 @@ LoanBrokerCoverDeposit::preclaim(PreclaimContext const& ctx)
     if (amount.asset() != vaultAsset)
         return tecWRONG_ASSET;
 
-    // Helper handles both IOU and MPT correctly without explicit branching.
-    if (auto const ret = canApplyToBrokerCover(
-            ctx.view, sleBroker, vaultAsset, amount, ctx.j, "LoanBrokerCoverDeposit"))
-        return ret;
-
     auto const pseudoAccountID = sleBroker->at(sfAccount);
     // Cannot transfer a non-transferable Asset
     if (auto const ret = canTransfer(ctx.view, vaultAsset, account, pseudoAccountID))
@@ -111,8 +106,6 @@ LoanBrokerCoverDeposit::doApply()
     auto const& tx = ctx_.tx;
 
     auto const brokerID = tx[sfLoanBrokerID];
-    auto const amount = tx[sfAmount];
-
     auto broker = view().peek(keylet::loanbroker(brokerID));
     if (!broker)
         return tecINTERNAL;  // LCOV_EXCL_LINE
@@ -122,9 +115,25 @@ LoanBrokerCoverDeposit::doApply()
         return tecINTERNAL;  // LCOV_EXCL_LINE
 
     auto const vaultAsset = vault->at(sfAsset);
-
     auto const brokerPseudoID = broker->at(sfAccount);
 
+    bool const fix320Enabled = view().rules().enabled(fixCleanup3_2_0);
+    auto const amount = [&]() -> STAmount {
+        if (!fix320Enabled)
+            return tx[sfAmount];
+
+        return roundToScale(
+            tx[sfAmount],
+            scale(broker->at(sfCoverAvailable), vaultAsset),
+            Number::RoundingMode::Downward);
+    }();
+
+    if (fix320Enabled && amount == beast::kZERO)
+    {
+        JLOG(ctx_.journal.warn()) << "LoanBrokerCoverDeposit: deposit amount: " << tx[sfAmount]
+                                  << "is zero at loan broker scale";
+        return tecPRECISION_LOSS;
+    }
     // Transfer assets from depositor to pseudo-account.
     if (auto ter = accountSend(view(), account_, brokerPseudoID, amount, j_, WaiveTransferFee::Yes))
         return ter;
diff --git a/src/test/app/LoanBroker_test.cpp b/src/test/app/LoanBroker_test.cpp
index c6e9065d79..48a8555655 100644
--- a/src/test/app/LoanBroker_test.cpp
+++ b/src/test/app/LoanBroker_test.cpp
@@ -1896,6 +1896,29 @@ class LoanBroker_test : public beast::unit_test::Suite
                 }
             }
 
+            {
+                testcase("Cover precision guard: Deposit");
+                // Both cases succeed; post-fix the amount is rounded DOWN to
+                // cover scale first, so the delta differs from pre-fix
+                // Input: 1.8e-14 IOU (sub-scale at cover scale -14)
+                //   Pre-fix:  10 + 1.8e-14 → round-to-nearest →
+                //             10.00000000000002 → delta 2e-14
+                //   Post-fix: roundToScale(1.8e-14, -14, Downward) = 1e-14;
+                //             10 + 1e-14 = 10.00000000000001 → delta 1e-14
+                Env env{*this, features};
+                auto const [brokerKeylet, iou] = setup(env);
+                PrettyAmount const subUlpAmt = iou(Number{18, -15});
+                auto const coverBefore = env.le(brokerKeylet)->at(sfCoverAvailable);
+                env(coverDeposit(alice, brokerKeylet.key, subUlpAmt), Ter(tesSUCCESS));
+                env.close();
+                auto const brokerAfter = env.le(brokerKeylet);
+                if (!BEAST_EXPECT(brokerAfter))
+                    return;
+
+                Number const delta = features[fixCleanup3_2_0] ? Number{1, -14} : Number{2, -14};
+                BEAST_EXPECT(brokerAfter->at(sfCoverAvailable) - coverBefore == delta);
+            }
+
             {
                 testcase("Cover precision guard: Withdraw");
                 Env env{*this, features};