diff --git a/pkg/rpc/client/doc.go b/pkg/rpc/client/doc.go
index 5ad1eac12..45c23706c 100644
--- a/pkg/rpc/client/doc.go
+++ b/pkg/rpc/client/doc.go
@@ -18,6 +18,7 @@ TODO:
 Supported methods
 
 	calculatenetworkfee
+	findstates
 	getapplicationlog
 	getbestblockhash
 	getblock
@@ -37,7 +38,9 @@ Supported methods
 	getpeers
 	getrawmempool
 	getrawtransaction
+	getstate
 	getstateheight
+	getstateroot
 	getstorage
 	gettransactionheight
 	getunclaimedgas
diff --git a/pkg/rpc/client/rpc.go b/pkg/rpc/client/rpc.go
index 2f43dd8e4..086876070 100644
--- a/pkg/rpc/client/rpc.go
+++ b/pkg/rpc/client/rpc.go
@@ -458,10 +458,19 @@ func (c *Client) GetState(stateroot util.Uint256, historicalContractHash util.Ui
 // If `maxCount` specified, then maximum number of items to be returned equals to `maxCount`.
 func (c *Client) FindStates(stateroot util.Uint256, historicalContractHash util.Uint160, historicalPrefix []byte,
 	start []byte, maxCount *int) (result.FindStates, error) {
+	if historicalPrefix == nil {
+		historicalPrefix = []byte{}
+	}
 	var (
-		params = request.NewRawParams(stateroot.StringLE(), historicalContractHash.StringLE(), historicalPrefix, historicalPrefix, start)
+		params = request.NewRawParams(stateroot.StringLE(), historicalContractHash.StringLE(), historicalPrefix)
 		resp   result.FindStates
 	)
+	if start == nil && maxCount != nil {
+		start = []byte{}
+	}
+	if start != nil {
+		params.Values = append(params.Values, start)
+	}
 	if maxCount != nil {
 		params.Values = append(params.Values, *maxCount)
 	}
@@ -471,6 +480,24 @@ func (c *Client) FindStates(stateroot util.Uint256, historicalContractHash util.
 	return resp, nil
 }
 
+// GetStateRootByHeight returns state root for the specified height.
+func (c *Client) GetStateRootByHeight(height uint32) (*state.MPTRoot, error) {
+	return c.getStateRoot(request.NewRawParams(height))
+}
+
+// GetStateRootByBlockHash returns state root for block with specified hash.
+func (c *Client) GetStateRootByBlockHash(hash util.Uint256) (*state.MPTRoot, error) {
+	return c.getStateRoot(request.NewRawParams(hash))
+}
+
+func (c *Client) getStateRoot(params request.RawParams) (*state.MPTRoot, error) {
+	var resp = new(state.MPTRoot)
+	if err := c.performRequest("getstateroot", params, resp); err != nil {
+		return nil, err
+	}
+	return resp, nil
+}
+
 // GetStateHeight returns current validated and local node state height.
 func (c *Client) GetStateHeight() (*result.StateHeight, error) {
 	var (
diff --git a/pkg/rpc/client/rpc_test.go b/pkg/rpc/client/rpc_test.go
index c4041c353..51c008785 100644
--- a/pkg/rpc/client/rpc_test.go
+++ b/pkg/rpc/client/rpc_test.go
@@ -769,6 +769,47 @@ var rpcClientTestCases = map[string][]rpcClientTestCase{
 			},
 		},
 	},
+	"getstateroot": {
+		{
+			name: "positive, by height",
+			invoke: func(c *Client) (interface{}, error) {
+				return c.GetStateRootByHeight(5)
+			},
+			serverResponse: `{"id":1,"jsonrpc":"2.0","result":{"version":0,"index":5,"roothash":"0x65d19151694321e70c6d184b37a2bcf7af4a2c60c099af332a4f7815e3670686","witnesses":[]}}`,
+			result: func(c *Client) interface{} {
+				h, err := util.Uint256DecodeStringLE("65d19151694321e70c6d184b37a2bcf7af4a2c60c099af332a4f7815e3670686")
+				if err != nil {
+					panic(err)
+				}
+				return &state.MPTRoot{
+					Version: 0,
+					Index:   5,
+					Root:    h,
+					Witness: []transaction.Witness{},
+				}
+			},
+		},
+		{
+			name: "positive, by hash",
+			invoke: func(c *Client) (interface{}, error) {
+				hash, err := util.Uint256DecodeStringLE("86fe1061140b2ea791b0739fb9732abc6e5e47de4927228a1ac41de3d93eb7cb")
+				if err != nil {
+					panic(err)
+				}
+				return c.GetStateRootByBlockHash(hash)
+			},
+			serverResponse: `{"id":1,"jsonrpc":"2.0","result":{"version":0,"index":5,"roothash":"0x65d19151694321e70c6d184b37a2bcf7af4a2c60c099af332a4f7815e3670686","witnesses":[]}}`,
+			result: func(c *Client) interface{} {
+				h, _ := util.Uint256DecodeStringLE("65d19151694321e70c6d184b37a2bcf7af4a2c60c099af332a4f7815e3670686")
+				return &state.MPTRoot{
+					Version: 0,
+					Index:   5,
+					Root:    h,
+					Witness: []transaction.Witness{},
+				}
+			},
+		},
+	},
 	"getstate": {
 		{
 			name: "positive",
diff --git a/pkg/rpc/server/server.go b/pkg/rpc/server/server.go
index 6ea513586..cd5f25763 100644
--- a/pkg/rpc/server/server.go
+++ b/pkg/rpc/server/server.go
@@ -1235,11 +1235,11 @@ func (s *Server) findStates(ps request.Params) (interface{}, *response.Error) {
 	}
 	csHash, err := ps.Value(1).GetUint160FromHex()
 	if err != nil {
-		return nil, response.WrapErrorWithData(response.ErrInvalidParams, errors.New("invalid contract hash"))
+		return nil, response.WrapErrorWithData(response.ErrInvalidParams, fmt.Errorf("invalid contract hash: %w", err))
 	}
 	prefix, err := ps.Value(2).GetBytesBase64()
 	if err != nil {
-		return nil, response.WrapErrorWithData(response.ErrInvalidParams, errors.New("invalid prefix"))
+		return nil, response.WrapErrorWithData(response.ErrInvalidParams, fmt.Errorf("invalid prefix: %w", err))
 	}
 	var (
 		key   []byte
@@ -1248,7 +1248,7 @@ func (s *Server) findStates(ps request.Params) (interface{}, *response.Error) {
 	if len(ps) > 3 {
 		key, err = ps.Value(3).GetBytesBase64()
 		if err != nil {
-			return nil, response.WrapErrorWithData(response.ErrInvalidParams, errors.New("invalid key"))
+			return nil, response.WrapErrorWithData(response.ErrInvalidParams, fmt.Errorf("invalid key: %w", err))
 		}
 		if len(key) > 0 {
 			if !bytes.HasPrefix(key, prefix) {
@@ -1263,7 +1263,7 @@ func (s *Server) findStates(ps request.Params) (interface{}, *response.Error) {
 	if len(ps) > 4 {
 		count, err = ps.Value(4).GetInt()
 		if err != nil {
-			return nil, response.WrapErrorWithData(response.ErrInvalidParams, errors.New("invalid count"))
+			return nil, response.WrapErrorWithData(response.ErrInvalidParams, fmt.Errorf("invalid count: %w", err))
 		}
 		if count > s.config.MaxFindResultItems {
 			count = s.config.MaxFindResultItems