diff --git a/pkg/compiler/analysis.go b/pkg/compiler/analysis.go
index b95139510..112c6945d 100644
--- a/pkg/compiler/analysis.go
+++ b/pkg/compiler/analysis.go
@@ -302,10 +302,6 @@ func isInteropPath(s string) bool {
 	return strings.HasPrefix(s, interopPrefix)
 }
 
-func isNativeHelpersPath(s string) bool {
-	return strings.HasPrefix(s, interopPrefix+"/native")
-}
-
 // canConvert returns true if type doesn't need to be converted on type assertion.
 func canConvert(s string) bool {
 	if len(s) != 0 && s[0] == '*' {
diff --git a/pkg/consensus/recovery_message_test.go b/pkg/consensus/recovery_message_test.go
index 3af23db91..9fe19e263 100644
--- a/pkg/consensus/recovery_message_test.go
+++ b/pkg/consensus/recovery_message_test.go
@@ -7,7 +7,6 @@ import (
 	"github.com/nspcc-dev/dbft/payload"
 	"github.com/nspcc-dev/neo-go/internal/testchain"
 	"github.com/nspcc-dev/neo-go/pkg/config/netmode"
-	"github.com/nspcc-dev/neo-go/pkg/crypto/keys"
 	"github.com/nspcc-dev/neo-go/pkg/util"
 	"github.com/stretchr/testify/require"
 )
@@ -157,16 +156,3 @@ func TestRecoveryMessage_Decode(t *testing.T) {
 	require.Equal(t, gio.EOF, buf.Err)
 }
 */
-
-func getKeys(t *testing.T, n int) []*privateKey {
-	privs := make([]*privateKey, 0, n)
-	for i := 0; i < n; i++ {
-		priv, err := keys.NewPrivateKey()
-		require.NoError(t, err)
-		require.NotNil(t, priv)
-
-		privs = append(privs, &privateKey{PrivateKey: priv})
-	}
-
-	return privs
-}
diff --git a/pkg/core/helper_test.go b/pkg/core/helper_test.go
index 41b0da005..32a470175 100644
--- a/pkg/core/helper_test.go
+++ b/pkg/core/helper_test.go
@@ -15,7 +15,6 @@ import (
 	"time"
 
 	"github.com/nspcc-dev/neo-go/internal/testchain"
-	"github.com/nspcc-dev/neo-go/internal/testserdes"
 	"github.com/nspcc-dev/neo-go/pkg/compiler"
 	"github.com/nspcc-dev/neo-go/pkg/config"
 	"github.com/nspcc-dev/neo-go/pkg/core/block"
@@ -28,7 +27,6 @@ import (
 	"github.com/nspcc-dev/neo-go/pkg/core/state"
 	"github.com/nspcc-dev/neo-go/pkg/core/storage"
 	"github.com/nspcc-dev/neo-go/pkg/core/transaction"
-	"github.com/nspcc-dev/neo-go/pkg/crypto/hash"
 	"github.com/nspcc-dev/neo-go/pkg/crypto/keys"
 	"github.com/nspcc-dev/neo-go/pkg/encoding/fixedn"
 	"github.com/nspcc-dev/neo-go/pkg/io"
@@ -180,51 +178,6 @@ func TestBug1728(t *testing.T) {
 	require.Equal(t, aer.VMState, vm.HaltState)
 }
 
-func getDecodedBlock(t *testing.T, i int) *block.Block {
-	data, err := getBlockData(i)
-	require.NoError(t, err)
-
-	b, err := hex.DecodeString(data["raw"].(string))
-	require.NoError(t, err)
-
-	block := block.New(false)
-	require.NoError(t, testserdes.DecodeBinary(b, block))
-
-	return block
-}
-
-func getBlockData(i int) (map[string]interface{}, error) {
-	b, err := ioutil.ReadFile(fmt.Sprintf("test_data/block_%d.json", i))
-	if err != nil {
-		return nil, err
-	}
-	var data map[string]interface{}
-	if err := json.Unmarshal(b, &data); err != nil {
-		return nil, err
-	}
-	return data, err
-}
-
-func newDumbBlock() *block.Block {
-	return &block.Block{
-		Header: block.Header{
-			Version:       0,
-			PrevHash:      hash.Sha256([]byte("a")),
-			MerkleRoot:    hash.Sha256([]byte("b")),
-			Timestamp:     100500,
-			Index:         1,
-			NextConsensus: hash.Hash160([]byte("a")),
-			Script: transaction.Witness{
-				VerificationScript: []byte{0x51}, // PUSH1
-				InvocationScript:   []byte{0x61}, // NOP
-			},
-		},
-		Transactions: []*transaction.Transaction{
-			transaction.New([]byte{byte(opcode.PUSH1)}, 0),
-		},
-	}
-}
-
 // This function generates "../rpc/testdata/testblocks.acc" file which contains data
 // for RPC unit tests. It also is a nice integration test.
 // To generate new "../rpc/testdata/testblocks.acc", follow the steps:
diff --git a/pkg/core/interop_system_test.go b/pkg/core/interop_system_test.go
index 7c6f714ef..298bf29e9 100644
--- a/pkg/core/interop_system_test.go
+++ b/pkg/core/interop_system_test.go
@@ -7,7 +7,6 @@ import (
 	"testing"
 
 	"github.com/nspcc-dev/neo-go/internal/random"
-	"github.com/nspcc-dev/neo-go/pkg/core/block"
 	"github.com/nspcc-dev/neo-go/pkg/core/dao"
 	"github.com/nspcc-dev/neo-go/pkg/core/interop"
 	"github.com/nspcc-dev/neo-go/pkg/core/interop/contract"
@@ -451,27 +450,6 @@ func createVM(t *testing.T) (*vm.VM, *interop.Context, *Blockchain) {
 	return v, context, chain
 }
 
-func createVMAndPushBlock(t *testing.T) (*vm.VM, *block.Block, *interop.Context, *Blockchain) {
-	v, block, context, chain := createVMAndBlock(t)
-	v.Estack().PushVal(stackitem.NewInterop(block))
-	return v, block, context, chain
-}
-
-func createVMAndBlock(t *testing.T) (*vm.VM, *block.Block, *interop.Context, *Blockchain) {
-	block := newDumbBlock()
-	chain := newTestChain(t)
-	d := dao.NewSimple(storage.NewMemoryStore(), chain.GetConfig().StateRootInHeader)
-	context := chain.newInteropContext(trigger.Application, d, block, nil)
-	v := context.SpawnVM()
-	return v, block, context, chain
-}
-
-func createVMAndPushTX(t *testing.T) (*vm.VM, *transaction.Transaction, *interop.Context, *Blockchain) {
-	v, tx, context, chain := createVMAndTX(t)
-	v.Estack().PushVal(stackitem.NewInterop(tx))
-	return v, tx, context, chain
-}
-
 func createVMAndContractState(t *testing.T) (*vm.VM, *state.Contract, *interop.Context, *Blockchain) {
 	script := []byte("testscript")
 	m := manifest.NewManifest("Test")
diff --git a/pkg/core/native/ledger.go b/pkg/core/native/ledger.go
index 88e86f87e..4dfd6b313 100644
--- a/pkg/core/native/ledger.go
+++ b/pkg/core/native/ledger.go
@@ -25,14 +25,7 @@ type Ledger struct {
 	interop.ContractMD
 }
 
-const (
-	ledgerContractID = -4
-
-	prefixBlockHash    = 9
-	prefixCurrentBlock = 12
-	prefixBlock        = 5
-	prefixTransaction  = 11
-)
+const ledgerContractID = -4
 
 // newLedger creates new Ledger native contract.
 func newLedger() *Ledger {
diff --git a/pkg/core/native/util.go b/pkg/core/native/util.go
index af7ffd6e7..73ac7f316 100644
--- a/pkg/core/native/util.go
+++ b/pkg/core/native/util.go
@@ -1,13 +1,11 @@
 package native
 
 import (
-	"encoding/binary"
 	"encoding/hex"
 	"fmt"
 	"math/big"
 
 	"github.com/nspcc-dev/neo-go/pkg/core/dao"
-	"github.com/nspcc-dev/neo-go/pkg/core/state"
 	"github.com/nspcc-dev/neo-go/pkg/core/storage"
 	"github.com/nspcc-dev/neo-go/pkg/encoding/bigint"
 	"github.com/nspcc-dev/neo-go/pkg/io"
@@ -36,34 +34,6 @@ func putSerializableToDAO(id int32, d dao.DAO, key []byte, item io.Serializable)
 	return d.PutStorageItem(id, key, w.Bytes())
 }
 
-func getInt64WithKey(id int32, d dao.DAO, key []byte, defaultValue int64) int64 {
-	si := d.GetStorageItem(id, key)
-	if si == nil {
-		return defaultValue
-	}
-	return int64(binary.LittleEndian.Uint64(si))
-}
-
-func setInt64WithKey(id int32, dao dao.DAO, key []byte, value int64) error {
-	si := make(state.StorageItem, 8)
-	binary.LittleEndian.PutUint64(si, uint64(value))
-	return dao.PutStorageItem(id, key, si)
-}
-
-func getUint32WithKey(id int32, dao dao.DAO, key []byte, defaultValue uint32) uint32 {
-	si := dao.GetStorageItem(id, key)
-	if si == nil {
-		return defaultValue
-	}
-	return binary.LittleEndian.Uint32(si)
-}
-
-func setUint32WithKey(id int32, dao dao.DAO, key []byte, value uint32) error {
-	si := make(state.StorageItem, 4)
-	binary.LittleEndian.PutUint32(si, value)
-	return dao.PutStorageItem(id, key, si)
-}
-
 func setIntWithKey(id int32, dao dao.DAO, key []byte, value int64) error {
 	return dao.PutStorageItem(id, key, bigint.ToBytes(big.NewInt(value)))
 }
diff --git a/pkg/core/util.go b/pkg/core/util.go
index 2c1750ab8..325bac560 100644
--- a/pkg/core/util.go
+++ b/pkg/core/util.go
@@ -14,17 +14,6 @@ import (
 	"github.com/nspcc-dev/neo-go/pkg/vm/opcode"
 )
 
-var (
-	// governingTokenTX represents transaction that is used to create
-	// governing (NEO) token. It's a part of the genesis block.
-	governingTokenTX transaction.Transaction
-
-	// utilityTokenTX represents transaction that is used to create
-	// utility (GAS) token. It's a part of the genesis block. It's mostly
-	// useful for its hash that represents GAS asset ID.
-	utilityTokenTX transaction.Transaction
-)
-
 // createGenesisBlock creates a genesis block based on the given configuration.
 func createGenesisBlock(cfg config.ProtocolConfiguration) (*block.Block, error) {
 	validators, err := validatorsFromConfig(cfg)
diff --git a/pkg/encoding/fixedn/fixed8.go b/pkg/encoding/fixedn/fixed8.go
index ff92e6b6d..01abc8720 100644
--- a/pkg/encoding/fixedn/fixed8.go
+++ b/pkg/encoding/fixedn/fixed8.go
@@ -1,7 +1,6 @@
 package fixedn
 
 import (
-	"errors"
 	"strconv"
 	"strings"
 
@@ -13,8 +12,6 @@ const (
 	decimals  = 100000000
 )
 
-var errInvalidString = errors.New("fixed8 must satisfy following regex \\d+(\\.\\d{1,8})?")
-
 // Fixed8 represents a fixed-point number with precision 10^-8.
 type Fixed8 int64
 
diff --git a/pkg/io/size.go b/pkg/io/size.go
index 93f7021f8..3075a77db 100644
--- a/pkg/io/size.go
+++ b/pkg/io/size.go
@@ -5,18 +5,6 @@ import (
 	"reflect"
 )
 
-var (
-	bit8 byte
-	ui8  uint8
-	ui16 uint16
-	ui32 uint32
-	ui64 uint64
-	i8   int8
-	i16  int16
-	i32  int32
-	i64  int64
-)
-
 // This structure is used to calculate the wire size of the serializable
 // structure. It's an io.Writer that doesn't do any real writes, but instead
 // just counts the number of bytes to be written.
diff --git a/pkg/network/payload/extensible.go b/pkg/network/payload/extensible.go
index 529a8dc37..66891e7e7 100644
--- a/pkg/network/payload/extensible.go
+++ b/pkg/network/payload/extensible.go
@@ -2,7 +2,6 @@ package payload
 
 import (
 	"errors"
-	"math"
 
 	"github.com/nspcc-dev/neo-go/pkg/core/transaction"
 	"github.com/nspcc-dev/neo-go/pkg/crypto/hash"
@@ -10,10 +9,7 @@ import (
 	"github.com/nspcc-dev/neo-go/pkg/util"
 )
 
-const (
-	maxExtensibleCategorySize = 32
-	maxExtensibleDataSize     = math.MaxUint16
-)
+const maxExtensibleCategorySize = 32
 
 // Extensible represents payload containing arbitrary data.
 type Extensible struct {
diff --git a/pkg/network/server.go b/pkg/network/server.go
index e5f9f8e96..3e5d00808 100644
--- a/pkg/network/server.go
+++ b/pkg/network/server.go
@@ -41,12 +41,10 @@ const (
 var (
 	errAlreadyConnected = errors.New("already connected")
 	errIdenticalID      = errors.New("identical node id")
-	errInvalidHandshake = errors.New("invalid handshake")
 	errInvalidNetwork   = errors.New("invalid network")
 	errMaxPeers         = errors.New("max peers reached")
 	errServerShutdown   = errors.New("server shutdown")
 	errInvalidInvType   = errors.New("invalid inventory type")
-	errInvalidHashStart = errors.New("invalid requested HashStart")
 )
 
 type (
diff --git a/pkg/rpc/client/client.go b/pkg/rpc/client/client.go
index bccd0d4a5..d112ef33c 100644
--- a/pkg/rpc/client/client.go
+++ b/pkg/rpc/client/client.go
@@ -21,7 +21,6 @@ import (
 const (
 	defaultDialTimeout    = 4 * time.Second
 	defaultRequestTimeout = 4 * time.Second
-	defaultClientVersion  = "2.0"
 	// number of blocks after which cache is expired
 	cacheTimeout = 100
 )
diff --git a/pkg/rpc/server/server_test.go b/pkg/rpc/server/server_test.go
index 526c54f2a..bd9df957b 100644
--- a/pkg/rpc/server/server_test.go
+++ b/pkg/rpc/server/server_test.go
@@ -46,11 +46,6 @@ type executor struct {
 	httpSrv *httptest.Server
 }
 
-const (
-	defaultJSONRPC = "2.0"
-	defaultID      = 1
-)
-
 type rpcTestCase struct {
 	name   string
 	params string
@@ -66,7 +61,6 @@ const genesisBlockHash = "73fe50b5564d57118296cbab0a78fe7cb11c97b7699d07a9a21fab
 const verifyContractHash = "c50082e0d8364d61ce6933bd24027a3363474dce"
 const verifyContractAVM = "VwMAQS1RCDAhcAwU7p6iLCfjS9AUj8QQjgj3To9QSLLbMHFoE87bKGnbKJdA"
 const verifyWithArgsContractHash = "8744ffdd07af8e9f18ab90685c8c2ebfd37c6415"
-const verifyWithArgsContractAVM = "VwIDeAwLZ29vZF9zdHJpbmeXJA15FSgJehHbIJciBRHbIHBoQA=="
 const invokescriptContractAVM = "VwcADBQBDAMOBQYMDQIODw0DDgcJAAAAANswcGhB+CfsjCGqJgQRQAwUDQ8DAgkAAgEDBwMEBQIBAA4GDAnbMHFpQfgn7IwhqiYEEkATQA=="
 
 var rpcTestCases = map[string][]rpcTestCase{
diff --git a/pkg/services/oracle/neofs/neofs.go b/pkg/services/oracle/neofs/neofs.go
index ee09ae424..199310569 100644
--- a/pkg/services/oracle/neofs/neofs.go
+++ b/pkg/services/oracle/neofs/neofs.go
@@ -3,7 +3,6 @@ package neofs
 import (
 	"bytes"
 	"context"
-	"crypto/sha256"
 	"errors"
 	"fmt"
 	"net/url"
@@ -24,10 +23,6 @@ const (
 	// URIScheme is the name of neofs URI scheme.
 	URIScheme = "neofs"
 
-	// containerIDSize is the size of container id in bytes.
-	containerIDSize = sha256.Size
-	// objectIDSize is the size of container id in bytes.
-	objectIDSize = sha256.Size
 	// rangeSep is a separator between offset and length.
 	rangeSep = '|'
 
diff --git a/pkg/util/bitfield/bitfield.go b/pkg/util/bitfield/bitfield.go
index 8766c8d60..c2de953b4 100644
--- a/pkg/util/bitfield/bitfield.go
+++ b/pkg/util/bitfield/bitfield.go
@@ -10,7 +10,6 @@ type Field []uint64
 
 // Bits and bytes count in a basic element of Field.
 const elemBits = 64
-const elemBytes = 8
 
 // New creates a new bit field of specified length. Actual field length
 // can be rounded to the next multiple of 64, so it's a responsibility
diff --git a/pkg/wallet/account.go b/pkg/wallet/account.go
index 93f0c983f..f67a4fc17 100644
--- a/pkg/wallet/account.go
+++ b/pkg/wallet/account.go
@@ -61,18 +61,6 @@ type Contract struct {
 	Deployed bool `json:"deployed"`
 }
 
-// contract is an intermediate struct used for json unmarshalling.
-type contract struct {
-	// Script is a hex-encoded script of the contract.
-	Script string `json:"script"`
-
-	// A list of parameters used deploying this contract.
-	Parameters []ContractParam `json:"parameters"`
-
-	// Indicates whether the contract has been deployed to the blockchain.
-	Deployed bool `json:"deployed"`
-}
-
 // ContractParam is a descriptor of a contract parameter
 // containing type and optional name.
 type ContractParam struct {