diff --git a/src/consensus/consensus.h b/src/consensus/consensus.h
index 1ae4e59f92..1371a0d07e 100644
--- a/src/consensus/consensus.h
+++ b/src/consensus/consensus.h
@@ -36,6 +36,7 @@ static const unsigned int MAX_BLOCK_BASE_SIZE = 2000000;
 static const int64_t MAX_BLOCK_SIGOPS_COST = 400000;
 /** The maximum allowed size of version 3 extra payload */
 static const unsigned int MAX_TX_EXTRA_PAYLOAD = 150000;
+static const unsigned int NEW_MAX_TX_EXTRA_PAYLOAD = 230000;
 /** Coinbase transaction outputs can only be spent after this number of new blocks (network rule) */
 static const int COINBASE_MATURITY = 100;
 
diff --git a/src/lelantus.cpp b/src/lelantus.cpp
index 95e45e2fab..af4fd8ffd7 100644
--- a/src/lelantus.cpp
+++ b/src/lelantus.cpp
@@ -421,6 +421,13 @@ bool CheckLelantusJoinSplitTransaction(
                          "CTransaction::CheckLelantusJoinSplitTransaction() : Error: incorrect joinsplit transaction verion");
     }
 
+    if (joinsplit->isSigmaToLelantus() && height >= params.stage4StartBlock) {
+        return state.DoS(100,
+                         false,
+                         NSEQUENCE_INCORRECT,
+                         "CTransaction::CheckLelantusJoinSplitTransaction() : Sigma pool already closed.");
+    }
+
     uint256 txHashForMetadata;
 
     // Obtain the hash of the transaction sans the zerocoin part
diff --git a/src/validation.cpp b/src/validation.cpp
index 5cba58e368..cbc8b6b258 100644
--- a/src/validation.cpp
+++ b/src/validation.cpp
@@ -662,7 +662,7 @@ bool CheckTransaction(const CTransaction &tx, CValidationState &state, bool fChe
     // Size limits (this doesn't take the witness into account, as that hasn't been checked for malleability)
     if (::GetSerializeSize(tx, SER_NETWORK, PROTOCOL_VERSION | SERIALIZE_TRANSACTION_NO_WITNESS) > MAX_BLOCK_BASE_SIZE)
         return state.DoS(100, false, REJECT_INVALID, "bad-txns-oversize");
-    if (tx.vExtraPayload.size() > MAX_TX_EXTRA_PAYLOAD)
+    if ((tx.vExtraPayload.size() > MAX_TX_EXTRA_PAYLOAD && nHeight < ::Params().GetConsensus().stage4StartBlock) || tx.vExtraPayload.size() > NEW_MAX_TX_EXTRA_PAYLOAD)
         return state.DoS(100, false, REJECT_INVALID, "bad-txns-payload-oversize");
 
     // Check for negative or overflow output values
@@ -964,6 +964,11 @@ bool AcceptToMemoryPoolWorker(CTxMemPool& pool, CValidationState& state, const C
             const std::vector<uint32_t> &ids = joinsplit->getCoinGroupIds();
             const std::vector<Scalar>& serials = joinsplit->getCoinSerialNumbers();
 
+            if (joinsplit->isSigmaToLelantus() && chainActive.Height() >= consensus.stage4StartBlock) {
+                    return state.DoS(100, error("Sigma pool already closed."),
+                                     REJECT_INVALID, "txn-invalid-lelantus-joinsplit");
+            }
+
             if (serials.size() != ids.size())
                 return state.Invalid(false, REJECT_CONFLICT, "txn-invalid-lelantus-joinsplit");
 
diff --git a/src/wallet/lelantusjoinsplitbuilder.cpp b/src/wallet/lelantusjoinsplitbuilder.cpp
index eba439524c..c6ef7363eb 100644
--- a/src/wallet/lelantusjoinsplitbuilder.cpp
+++ b/src/wallet/lelantusjoinsplitbuilder.cpp
@@ -193,6 +193,9 @@ CWalletTx LelantusJoinSplitBuilder::Build(
 
         std::vector<sigma::CoinDenomination> denomChanges;
         try {
+            if (chainActive.Height() >= Params().GetConsensus().stage4StartBlock)
+                throw std::runtime_error(_("Sigma pool already closed."));
+
             CAmount availableBalance(0);
             for (auto coin : sigmaCoins) {
                 availableBalance += coin.get_denomination_value();