diff --git a/cmd/rpc/query.go b/cmd/rpc/query.go
index 5875f2de..2a13cd85 100644
--- a/cmd/rpc/query.go
+++ b/cmd/rpc/query.go
@@ -284,11 +284,20 @@ func (s *Server) Order(w http.ResponseWriter, r *http.Request, _ httprouter.Para
 // Orders retrieves the order book for a committee with optional filters and pagination
 func (s *Server) Orders(w http.ResponseWriter, r *http.Request, _ httprouter.Params) {
 	// Invoke helper with the HTTP request, response writer and an inline callback
-	s.ordersParams(w, r, func(s *fsm.StateMachine, req *ordersRequest) (any, lib.ErrorI) {
+	s.ordersParams(w, r, func(sm *fsm.StateMachine, req *ordersRequest) (any, lib.ErrorI) {
 		// validate mutual exclusion: cannot filter by both seller and buyer address
 		if req.SellersSendAddress != "" && req.BuyerSendAddress != "" {
 			return nil, lib.NewError(lib.CodeInvalidArgument, lib.RPCModule, "cannot filter by both sellersSendAddress and buyerSendAddress")
 		}
+		// validate that address-based queries are only allowed when indexing is enabled
+		if !sm.Config.StateMachineConfig.IndexOrdersByAddresses {
+			if req.SellersSendAddress != "" {
+				return nil, lib.NewError(lib.CodeInvalidArgument, lib.RPCModule, "sellersSendAddress filtering is disabled; set indexOrdersByAddresses=true in config")
+			}
+			if req.BuyerSendAddress != "" {
+				return nil, lib.NewError(lib.CodeInvalidArgument, lib.RPCModule, "buyerSendAddress filtering is disabled; set indexOrdersByAddresses=true in config")
+			}
+		}
 		// convert seller address if provided
 		var sellerAddr []byte
 		if req.SellersSendAddress != "" {
@@ -308,7 +317,7 @@ func (s *Server) Orders(w http.ResponseWriter, r *http.Request, _ httprouter.Par
 			}
 		}
 		// use paginated query
-		return s.GetOrdersPaginated(sellerAddr, buyerAddr, req.Committee, req.PageParams)
+		return sm.GetOrdersPaginated(sellerAddr, buyerAddr, req.Committee, req.PageParams)
 	})
 }
 
diff --git a/fsm/swap.go b/fsm/swap.go
index f97dbdd8..f65c81b9 100644
--- a/fsm/swap.go
+++ b/fsm/swap.go
@@ -276,21 +276,28 @@ func (s *StateMachine) SetOrder(order *lib.SellOrder, chainId uint64) (err lib.E
 	if err = s.Set(KeyForOrder(chainId, order.Id), protoBytes); err != nil {
 		return
 	}
-	// set the secondary index for seller address lookup (value is empty, key is sufficient)
-	if err = s.Set(KeyForOrderBySeller(order.SellersSendAddress, chainId, order.Id), []byte{}); err != nil {
-		return
-	}
-	// set the secondary index for buyer address lookup if buyer exists (locked order)
-	if len(order.BuyerSendAddress) > 0 {
-		if err = s.Set(KeyForOrderByBuyer(order.BuyerSendAddress, chainId, order.Id), []byte{}); err != nil {
+	// set secondary indexes only if configured
+	if s.Config.StateMachineConfig.IndexOrdersByAddresses {
+		// set the secondary index for seller address lookup (value is empty, key is sufficient)
+		if err = s.Set(KeyForOrderBySeller(order.SellersSendAddress, chainId, order.Id), []byte{}); err != nil {
 			return
 		}
+		// set the secondary index for buyer address lookup if buyer exists (locked order)
+		if len(order.BuyerSendAddress) > 0 {
+			if err = s.Set(KeyForOrderByBuyer(order.BuyerSendAddress, chainId, order.Id), []byte{}); err != nil {
+				return
+			}
+		}
 	}
 	return
 }
 
 // cleanupStaleBuyerIndex() removes the old buyer index entry if the buyer changed or was removed
 func (s *StateMachine) cleanupStaleBuyerIndex(order *lib.SellOrder, chainId uint64) lib.ErrorI {
+	// skip if indexing is disabled
+	if !s.Config.StateMachineConfig.IndexOrdersByAddresses {
+		return nil
+	}
 	// check if order already exists
 	existingOrder, err := s.GetOrder(order.Id, chainId)
 	// if order not found, nothing to clean up
@@ -321,15 +328,18 @@ func (s *StateMachine) DeleteOrder(orderId []byte, chainId uint64) (err lib.Erro
 	if err = s.Delete(KeyForOrder(chainId, orderId)); err != nil {
 		return
 	}
-	// delete the seller secondary index entry
-	if err = s.Delete(KeyForOrderBySeller(order.SellersSendAddress, chainId, orderId)); err != nil {
-		return
-	}
-	// delete the buyer secondary index entry if buyer exists
-	if len(order.BuyerSendAddress) > 0 {
-		if err = s.Delete(KeyForOrderByBuyer(order.BuyerSendAddress, chainId, orderId)); err != nil {
+	// delete secondary indexes only if configured
+	if s.Config.StateMachineConfig.IndexOrdersByAddresses {
+		// delete the seller secondary index entry
+		if err = s.Delete(KeyForOrderBySeller(order.SellersSendAddress, chainId, orderId)); err != nil {
 			return
 		}
+		// delete the buyer secondary index entry if buyer exists
+		if len(order.BuyerSendAddress) > 0 {
+			if err = s.Delete(KeyForOrderByBuyer(order.BuyerSendAddress, chainId, orderId)); err != nil {
+				return
+			}
+		}
 	}
 	return
 }
diff --git a/lib/config.go b/lib/config.go
index 1579f816..54ba35da 100644
--- a/lib/config.go
+++ b/lib/config.go
@@ -158,21 +158,25 @@ const (
 	DefaultInitialTokensPerBlock = uint64(80 * 1000000) // 80 CNPY
 	// the number of blocks between each halvening (block reward is cut in half) event
 	DefaultBlocksPerHalvening = uint64(3150000) // ~ 2 years - 20 second blocks
+	// whether to index orders by seller/buyer address for efficient lookups
+	DefaultIndexOrdersByAddresses = true
 )
 
 // StateMachineConfig houses FSM level options
 type StateMachineConfig struct {
-	InitialTokensPerBlock uint64 `json:"initialTokensPerBlock"` // initial micro tokens minted per block (before halvenings)
-	BlocksPerHalvening    uint64 `json:"blocksPerHalvening"`    // number of blocks between block reward halvings
-	FaucetAddress         string `json:"faucetAddress"`         // if set: "send" txs from this address will auto-mint on insufficient funds (dev/test only)
+	InitialTokensPerBlock  uint64 `json:"initialTokensPerBlock"`  // initial micro tokens minted per block (before halvenings)
+	BlocksPerHalvening     uint64 `json:"blocksPerHalvening"`     // number of blocks between block reward halvings
+	FaucetAddress          string `json:"faucetAddress"`          // if set: "send" txs from this address will auto-mint on insufficient funds (dev/test only)
+	IndexOrdersByAddresses bool   `json:"indexOrdersByAddresses"` // index orders by seller/buyer address for efficient lookups
 }
 
 // DefaultStateMachineConfig returns FSM defaults
 func DefaultStateMachineConfig() StateMachineConfig {
 	return StateMachineConfig{
-		InitialTokensPerBlock: DefaultInitialTokensPerBlock,
-		BlocksPerHalvening:    DefaultBlocksPerHalvening,
-		FaucetAddress:         "",
+		InitialTokensPerBlock:  DefaultInitialTokensPerBlock,
+		BlocksPerHalvening:     DefaultBlocksPerHalvening,
+		FaucetAddress:          "",
+		IndexOrdersByAddresses: DefaultIndexOrdersByAddresses,
 	}
 }