diff --git a/src/masternodes/mn_checks.cpp b/src/masternodes/mn_checks.cpp
index 8feb5effcb1..0200c746f2f 100644
--- a/src/masternodes/mn_checks.cpp
+++ b/src/masternodes/mn_checks.cpp
@@ -65,6 +65,7 @@ std::string ToString(CustomTxType type) {
         case CustomTxType::Vault:               return "Vault";
         case CustomTxType::UpdateVault:         return "UpdateVault";
         case CustomTxType::DepositToVault:      return "DepositToVault";
+        case CustomTxType::AuctionBid:          return "AuctionBid";
         case CustomTxType::None:                return "None";
     }
     return "None";
@@ -149,6 +150,7 @@ CCustomTxMessage customTypeToMessage(CustomTxType txType) {
         case CustomTxType::Vault:                   return CVaultMessage{};
         case CustomTxType::UpdateVault:             return CUpdateVaultMessage{};
         case CustomTxType::DepositToVault:          return CDepositToVaultMessage{};
+        case CustomTxType::AuctionBid:              return CAuctionBidMessage{};
         case CustomTxType::None:                    return CCustomTxMessageNone{};
     }
     return CCustomTxMessageNone{};
@@ -455,6 +457,11 @@ class CCustomMetadataParseVisitor : public boost::static_visitor<Res>
         return !res ? res : serialize(obj);
     }
 
+    Res operator()(CAuctionBidMessage& obj) const {
+        auto res = isPostFortCanningFork();
+        return !res ? res : serialize(obj);
+    }
+
     Res operator()(CCustomTxMessageNone&) const {
         return Res::Ok();
     }
@@ -2150,6 +2157,47 @@ class CCustomTxApplyVisitor : public CCustomTxVisitor
         return Res::Ok();
     }
 
+    Res operator()(const CAuctionBidMessage& obj) const {
+        // owner auth
+        if (!HasAuth(obj.from)) {
+            return Res::Err("tx must have at least one input from token owner");
+        }
+        // vault exists
+        auto vault = mnview.GetVault(obj.vaultId);
+        if (!vault)
+            return Res::Err("Cannot find existing vault with id %s", obj.vaultId.GetHex());
+
+        // vault under liquidation
+        if (!vault.val->isUnderLiquidation)
+            return Res::Err("Cannot bid to vault which is not under liquidation");
+
+        auto data = mnview.GetAuction(obj.vaultId, height);
+        if (!data)
+            return Res::Err("No auction data to vault/index %s/%d", obj.vaultId.GetHex(), obj.index);
+
+        auto batch = mnview.GetAuctionBatch(obj.vaultId, obj.index);
+        if (!batch)
+            return Res::Err("No batch to vault/index %s/%d", obj.vaultId.GetHex(), obj.index);
+
+        auto bid = mnview.GetAuctionBid(obj.vaultId, obj.index);
+        if (!bid) {
+            auto amount = MultiplyAmounts(batch->loanAmount.nValue,  COIN + data->liquidationPenalty);
+            if (amount > obj.amount.nValue)
+                return Res::Err("First bid should include liquidation penalty of %d%%", data->liquidationPenalty * 100 / COIN);
+        } else {
+            auto amount = MultiplyAmounts(bid->second.nValue,  COIN + (COIN / 100));
+            if (amount > obj.amount.nValue)
+                return Res::Err("Bid override should be at least 1%% higher than current one");
+            // immediate refund previous bid
+            CalculateOwnerRewards(bid->first);
+            mnview.AddBalance(bid->first, bid->second);
+        }
+        //check balance
+        CalculateOwnerRewards(obj.from);
+        auto res = mnview.SubBalance(obj.from, obj.amount);
+        return !res ? res : mnview.StoreAuctionBid(obj.vaultId, obj.index, {obj.from, obj.amount});
+    }
+
     Res operator()(const CCustomTxMessageNone&) const {
         return Res::Ok();
     }
diff --git a/src/masternodes/mn_checks.h b/src/masternodes/mn_checks.h
index 6c8ebaeda67..ffabc413802 100644
--- a/src/masternodes/mn_checks.h
+++ b/src/masternodes/mn_checks.h
@@ -83,7 +83,8 @@ enum class CustomTxType : uint8_t
     DestroyLoanScheme  = 'D',
     Vault              = 'V',
     UpdateVault        = 'v',
-    DepositToVault     = 'S'
+    DepositToVault     = 'S',
+    AuctionBid         = 'I'
 };
 
 inline CustomTxType CustomTxCodeToType(uint8_t ch) {
@@ -126,6 +127,7 @@ inline CustomTxType CustomTxCodeToType(uint8_t ch) {
         case CustomTxType::Vault:
         case CustomTxType::UpdateVault:
         case CustomTxType::DepositToVault:
+        case CustomTxType::AuctionBid:
         case CustomTxType::None:
             return type;
     }
@@ -282,7 +284,8 @@ typedef boost::variant<
     CDestroyLoanSchemeMessage,
     CVaultMessage,
     CUpdateVaultMessage,
-    CDepositToVaultMessage
+    CDepositToVaultMessage,
+    CAuctionBidMessage
 > CCustomTxMessage;
 
 CCustomTxMessage customTypeToMessage(CustomTxType txType);
diff --git a/src/masternodes/rpc_customtx.cpp b/src/masternodes/rpc_customtx.cpp
index cc0d53d6a9d..5731b0f293c 100644
--- a/src/masternodes/rpc_customtx.cpp
+++ b/src/masternodes/rpc_customtx.cpp
@@ -352,6 +352,14 @@ class CCustomTxRpcVisitor : public boost::static_visitor<void>
         rpcInfo.pushKV("from", ScriptToString(obj.from));
         rpcInfo.pushKV("amount", obj.amount.ToString());
     }
+
+    void operator()(const CAuctionBidMessage& obj) const {
+        rpcInfo.pushKV("vaultid", obj.vaultId.GetHex());
+        rpcInfo.pushKV("index", int64_t(obj.index));
+        rpcInfo.pushKV("from", ScriptToString(obj.from));
+        rpcInfo.pushKV("amount", obj.amount.ToString());
+    }
+
     void operator()(const CCustomTxMessageNone&) const {
     }
 };
diff --git a/src/masternodes/rpc_vault.cpp b/src/masternodes/rpc_vault.cpp
index 7069a017d0b..4a542b70e51 100644
--- a/src/masternodes/rpc_vault.cpp
+++ b/src/masternodes/rpc_vault.cpp
@@ -456,6 +456,96 @@ UniValue deposittovault(const JSONRPCRequest& request) {
     return signsend(rawTx, pwallet, optAuthTx)->GetHash().GetHex();
 }
 
+UniValue auctionbid(const JSONRPCRequest& request) {
+    CWallet *const pwallet = GetWallet(request);
+
+    RPCHelpMan{"auctionbid",
+               "Bid to vault in auction\n" +
+               HelpRequiringPassphrase(pwallet) + "\n",
+               {
+                    {"vaultid", RPCArg::Type::STR, RPCArg::Optional::NO, "Vault id"},
+                    {"index", RPCArg::Type::NUM, RPCArg::Optional::NO, "Auction index"},
+                    {"from", RPCArg::Type::STR, RPCArg::Optional::NO, "Address to get tokens"},
+                    {"amount", RPCArg::Type::STR, RPCArg::Optional::NO, "Amount of amount@symbol format"},
+                    {"inputs", RPCArg::Type::ARR, RPCArg::Optional::OMITTED_NAMED_ARG, "A json array of json objects",
+                        {
+                            {"", RPCArg::Type::OBJ, RPCArg::Optional::OMITTED, "",
+                                {
+                                    {"txid", RPCArg::Type::STR_HEX, RPCArg::Optional::NO, "The transaction id"},
+                                    {"vout", RPCArg::Type::NUM, RPCArg::Optional::NO, "The output number"},
+                                },
+                            },
+                        },
+                    }
+               },
+               RPCResult{
+                    "\"txid\"                  (string) The transaction id.\n"
+               },
+               RPCExamples{
+                       HelpExampleCli("auctionbid",
+                        "84b22eee1964768304e624c416f29a91d78a01dc5e8e12db26bdac0670c67bb2i 0 mwSDMvn1Hoc8DsoB7AkLv7nxdrf5Ja4jsF 100@TSLA") +
+                       HelpExampleRpc("deposittovault",
+                        "84b22eee1964768304e624c416f29a91d78a01dc5e8e12db26bdac0670c67bb2i 0 mwSDMvn1Hoc8DsoB7AkLv7nxdrf5Ja4jsF 1@DTSLA")
+               },
+    }.Check(request);
+
+    RPCTypeCheck(request.params,
+                 {UniValue::VSTR, UniValue::VNUM, UniValue::VSTR, UniValue::VSTR, UniValue::VARR},
+                 false);
+
+    if (pwallet->chain().isInitialBlockDownload())
+        throw JSONRPCError(RPC_CLIENT_IN_INITIAL_DOWNLOAD, "Cannot make auction bid while still in Initial Block Download");
+
+    pwallet->BlockUntilSyncedToCurrentChain();
+    LockedCoinsScopedGuard lcGuard(pwallet);
+
+    // decode vaultid
+    CVaultId vaultId = ParseHashV(request.params[0], "vaultid");
+    uint32_t index = request.params[1].get_int();
+    auto from = DecodeScript(request.params[2].get_str());
+    CTokenAmount amount = DecodeAmount(pwallet->chain(), request.params[3].get_str(), "amount");
+
+    CAuctionBidMessage msg{vaultId, index, from, amount};
+    CDataStream markedMetadata(DfTxMarker, SER_NETWORK, PROTOCOL_VERSION);
+    markedMetadata << static_cast<unsigned char>(CustomTxType::DepositToVault)
+                   << msg;
+    CScript scriptMeta;
+    scriptMeta << OP_RETURN << ToByteVector(markedMetadata);
+
+    int targetHeight = chainHeight(*pwallet->chain().lock()) + 1;
+
+    const auto txVersion = GetTransactionVersion(targetHeight);
+    CMutableTransaction rawTx(txVersion);
+
+    rawTx.vout.push_back(CTxOut(0, scriptMeta));
+
+    CTransactionRef optAuthTx;
+    std::set<CScript> auths{from};
+    rawTx.vin = GetAuthInputsSmart(pwallet, rawTx.nVersion, auths, false /*needFoundersAuth*/, optAuthTx, request.params[4]);
+
+    CCoinControl coinControl;
+
+     // Set change to from address
+    CTxDestination dest;
+    ExtractDestination(from, dest);
+    if (IsValidDestination(dest)) {
+        coinControl.destChange = dest;
+    }
+
+    fund(rawTx, pwallet, optAuthTx, &coinControl);
+
+    // check execution
+    {
+        LOCK(cs_main);
+        CCoinsViewCache coins(&::ChainstateActive().CoinsTip());
+        if (optAuthTx)
+            AddCoins(coins, *optAuthTx, targetHeight);
+        auto metadata = ToByteVector(CDataStream{SER_NETWORK, PROTOCOL_VERSION, msg});
+        execTestTx(CTransaction(rawTx), targetHeight, metadata, CAuctionBidMessage{}, coins);
+    }
+    return signsend(rawTx, pwallet, optAuthTx)->GetHash().GetHex();
+}
+
 static const CRPCCommand commands[] =
 {
 //  category        name                         actor (function)        params
@@ -465,6 +555,7 @@ static const CRPCCommand commands[] =
     {"vault",        "getvault",                  &getvault,              {"id"}},
     {"vault",        "updatevault",               &updatevault,           {"id", "parameters", "inputs"}},
     {"vault",        "deposittovault",            &deposittovault,        {"id", "from", "amount", "inputs"}},
+    {"vault",        "auctionbid",                &auctionbid,            {"id", "index", "from", "amount", "inputs"}},
 };
 
 void RegisterVaultRPCCommands(CRPCTable& tableRPC) {
diff --git a/src/masternodes/vault.cpp b/src/masternodes/vault.cpp
index 50a7bf3a1c6..fa33be565d6 100644
--- a/src/masternodes/vault.cpp
+++ b/src/masternodes/vault.cpp
@@ -110,6 +110,17 @@ Res CVaultView::EraseAuction(const CVaultId& vaultId, uint32_t height)
     return Res::Err("Auction for vault <%s> not found", vaultId.GetHex());
 }
 
+boost::optional<CAuctionData> CVaultView::GetAuction(const CVaultId& vaultId, uint32_t height)
+{
+    auto it = LowerBound<AuctionHeightKey>(std::make_pair(height, vaultId));
+    for (; it.Valid(); it.Next()) {
+        if (it.Key().second == vaultId) {
+            return it.Value().as<CAuctionData>();
+        }
+    }
+    return {};
+}
+
 Res CVaultView::StoreAuctionBatch(const CVaultId& vaultId, uint32_t id, const CAuctionBatch& batch)
 {
     WriteBy<AuctionBatchKey>(std::make_pair(vaultId, id), batch);
@@ -127,13 +138,10 @@ boost::optional<CAuctionBatch> CVaultView::GetAuctionBatch(const CVaultId& vault
     return ReadBy<AuctionBatchKey, CAuctionBatch>(std::make_pair(vaultId, id));
 }
 
-void CVaultView::ForEachVaultAuction(std::function<bool(const CVaultId&, const CAuctionData&)> callback, uint32_t height)
+void CVaultView::ForEachVaultAuction(std::function<bool(const CVaultId&, uint32_t, const CAuctionData&)> callback, uint32_t height)
 {
     ForEach<AuctionHeightKey, std::pair<uint32_t, CVaultId>, CAuctionData>([&](const std::pair<uint32_t, CVaultId>& pair, const CAuctionData& data) {
-        if (pair.first != height) {
-            return false;
-        }
-        return callback(pair.second, data);
+        return callback(pair.second, pair.first, data);
     }, std::make_pair(height, CVaultId{}));
 }
 
diff --git a/src/masternodes/vault.h b/src/masternodes/vault.h
index ade2b9bf1ec..34c832bf8de 100644
--- a/src/masternodes/vault.h
+++ b/src/masternodes/vault.h
@@ -60,6 +60,24 @@ struct CDepositToVaultMessage {
     }
 };
 
+struct CAuctionBidMessage {
+    CVaultId vaultId;
+    uint32_t index;
+    CScript from;
+    CTokenAmount amount;
+
+    ADD_SERIALIZE_METHODS;
+
+    template <typename Stream, typename Operation>
+    inline void SerializationOp(Stream& s, Operation ser_action)
+    {
+        READWRITE(vaultId);
+        READWRITE(index);
+        READWRITE(from);
+        READWRITE(amount);
+    }
+};
+
 struct CAuctionData {
     uint32_t batchCount;
     CAmount liquidationPenalty;
@@ -103,10 +121,11 @@ class CVaultView : public virtual CStorageView
 
     Res StoreAuction(const CVaultId& vaultId, uint32_t height, const CAuctionData& data);
     Res EraseAuction(const CVaultId& vaultId, uint32_t height);
+    boost::optional<CAuctionData> GetAuction(const CVaultId& vaultId, uint32_t height);
     Res StoreAuctionBatch(const CVaultId& vaultId, uint32_t id, const CAuctionBatch& batch);
     Res EraseAuctionBatch(const CVaultId& vaultId, uint32_t id);
     boost::optional<CAuctionBatch> GetAuctionBatch(const CVaultId& vaultId, uint32_t id);
-    void ForEachVaultAuction(std::function<bool(const CVaultId&, const CAuctionData&)> callback, uint32_t height);
+    void ForEachVaultAuction(std::function<bool(const CVaultId&, uint32_t, const CAuctionData&)> callback, uint32_t height = 0);
 
     using COwnerTokenAmount = std::pair<CScript, CTokenAmount>;
     Res StoreAuctionBid(const CVaultId& vaultId, uint32_t id, COwnerTokenAmount amount);
diff --git a/src/rpc/client.cpp b/src/rpc/client.cpp
index e5121c4997f..b306e4790e6 100644
--- a/src/rpc/client.cpp
+++ b/src/rpc/client.cpp
@@ -246,6 +246,7 @@ static const CRPCConvertParam vRPCConvertParams[] =
     { "updatevault", 1, "parameters" },
     { "updatevault", 2, "inputs" },
     { "deposittovault", 3, "inputs" },
+    { "auctionbid", 4, "inputs" },
 
     { "spv_sendrawtx", 0, "rawtx" },
     { "spv_createanchor", 0, "inputs" },
diff --git a/src/validation.cpp b/src/validation.cpp
index 439f156f230..544fbe320ec 100644
--- a/src/validation.cpp
+++ b/src/validation.cpp
@@ -2982,7 +2982,10 @@ bool CChainState::ConnectBlock(const CBlock& block, CValidationState& state, CBl
                     return true;
                 });
             }
-            cache.ForEachVaultAuction([&](const CVaultId& vaultId, const CAuctionData& data) {
+            cache.ForEachVaultAuction([&](const CVaultId& vaultId, uint32_t height, const CAuctionData& data) {
+                if (int(height) != pindex->nHeight) {
+                    return false;
+                }
                 std::set<DCT_ID> tokensLooseInterest;
                 for (uint32_t i = 0; i < data.batchCount; i++) {
                     auto batch = cache.GetAuctionBatch(vaultId, i);