diff --git a/cli/wallet_test.go b/cli/wallet_test.go
index bae2449d6..f78871cef 100644
--- a/cli/wallet_test.go
+++ b/cli/wallet_test.go
@@ -172,21 +172,48 @@ func TestClaimGas(t *testing.T) {
 	e := newExecutor(t, true)
 	defer e.Close(t)
 
-	start := e.Chain.BlockHeight()
-	balanceBefore := e.Chain.GetUtilityTokenBalance(validatorHash)
+	const walletPath = "testdata/testwallet.json"
+	w, err := wallet.NewWalletFromFile(walletPath)
+	require.NoError(t, err)
+	defer w.Close()
+
+	args := []string{
+		"neo-go", "wallet", "nep5", "multitransfer",
+		"--rpc-endpoint", "http://" + e.RPC.Addr,
+		"--wallet", validatorWallet,
+		"--from", validatorAddr,
+		"neo:" + w.Accounts[0].Address + ":1000",
+		"gas:" + w.Accounts[0].Address + ":1000", // for tx send
+	}
 	e.In.WriteString("one\r")
+	e.Run(t, args...)
+	e.checkTxPersisted(t)
+
+	h, err := address.StringToUint160(w.Accounts[0].Address)
+	require.NoError(t, err)
+
+	balanceBefore := e.Chain.GetUtilityTokenBalance(h)
+	claimHeight := e.Chain.BlockHeight() + 1
+	cl, err := e.Chain.CalculateClaimable(h, claimHeight)
+	require.NoError(t, err)
+	require.True(t, cl.Sign() > 0)
+
+	e.In.WriteString("testpass\r")
 	e.Run(t, "neo-go", "wallet", "claim",
 		"--rpc-endpoint", "http://"+e.RPC.Addr,
-		"--wallet", validatorWallet,
-		"--address", validatorAddr)
-	tx, end := e.checkTxPersisted(t)
-	b, _ := e.Chain.GetGoverningTokenBalance(validatorHash)
-	cl := e.Chain.CalculateClaimable(b, start, end)
-	require.True(t, cl.Sign() > 0)
-	cl.Sub(cl, big.NewInt(tx.NetworkFee+tx.SystemFee))
+		"--wallet", walletPath,
+		"--address", w.Accounts[0].Address)
+	tx, height := e.checkTxPersisted(t)
+	balanceBefore.Sub(balanceBefore, big.NewInt(tx.NetworkFee+tx.SystemFee))
+	balanceBefore.Add(balanceBefore, cl)
 
-	balanceAfter := e.Chain.GetUtilityTokenBalance(validatorHash)
-	require.Equal(t, 0, balanceAfter.Cmp(balanceBefore.Add(balanceBefore, cl)))
+	balanceAfter := e.Chain.GetUtilityTokenBalance(h)
+	// height can be bigger than claimHeight especially when tests are executed with -race.
+	if height == claimHeight {
+		require.Equal(t, 0, balanceAfter.Cmp(balanceBefore))
+	} else {
+		require.Equal(t, 1, balanceAfter.Cmp(balanceBefore))
+	}
 }
 
 func TestImportDeployed(t *testing.T) {
diff --git a/pkg/core/blockchain.go b/pkg/core/blockchain.go
index 81b705230..f575ed082 100644
--- a/pkg/core/blockchain.go
+++ b/pkg/core/blockchain.go
@@ -1156,10 +1156,8 @@ func (bc *Blockchain) UnsubscribeFromExecutions(ch chan<- *state.AppExecResult)
 
 // CalculateClaimable calculates the amount of GAS generated by owning specified
 // amount of NEO between specified blocks.
-func (bc *Blockchain) CalculateClaimable(value *big.Int, startHeight, endHeight uint32) *big.Int {
-	ic := bc.newInteropContext(trigger.Application, bc.dao, nil, nil)
-	res, _ := bc.contracts.NEO.CalculateNEOHolderReward(ic, value, startHeight, endHeight)
-	return res
+func (bc *Blockchain) CalculateClaimable(acc util.Uint160, endHeight uint32) (*big.Int, error) {
+	return bc.contracts.NEO.CalculateBonus(bc.dao, acc, endHeight)
 }
 
 // FeePerByte returns transaction network fee per byte.
diff --git a/pkg/core/blockchain_test.go b/pkg/core/blockchain_test.go
index dab65aa4b..d43b35fae 100644
--- a/pkg/core/blockchain_test.go
+++ b/pkg/core/blockchain_test.go
@@ -854,8 +854,9 @@ func TestGetClaimable(t *testing.T) {
 	require.NoError(t, err)
 
 	t.Run("first generation period", func(t *testing.T) {
-		amount := bc.CalculateClaimable(big.NewInt(1), 0, 2)
-		require.EqualValues(t, big.NewInt(1), amount)
+		amount, err := bc.CalculateClaimable(neoOwner, 1)
+		require.NoError(t, err)
+		require.EqualValues(t, big.NewInt(5*native.GASFactor/10), amount)
 	})
 }
 
diff --git a/pkg/core/blockchainer/blockchainer.go b/pkg/core/blockchainer/blockchainer.go
index 04e72b569..8158798d8 100644
--- a/pkg/core/blockchainer/blockchainer.go
+++ b/pkg/core/blockchainer/blockchainer.go
@@ -22,7 +22,7 @@ type Blockchainer interface {
 	AddHeaders(...*block.Header) error
 	AddBlock(*block.Block) error
 	AddStateRoot(r *state.MPTRoot) error
-	CalculateClaimable(value *big.Int, startHeight, endHeight uint32) *big.Int
+	CalculateClaimable(h util.Uint160, endHeight uint32) (*big.Int, error)
 	Close()
 	HeaderHeight() uint32
 	GetBlock(hash util.Uint256) (*block.Block, error)
diff --git a/pkg/core/native/native_neo.go b/pkg/core/native/native_neo.go
index 9922d8cd9..e182c2e95 100644
--- a/pkg/core/native/native_neo.go
+++ b/pkg/core/native/native_neo.go
@@ -15,6 +15,7 @@ import (
 	"github.com/nspcc-dev/neo-go/pkg/core/interop"
 	"github.com/nspcc-dev/neo-go/pkg/core/interop/runtime"
 	"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/crypto/hash"
 	"github.com/nspcc-dev/neo-go/pkg/crypto/keys"
 	"github.com/nspcc-dev/neo-go/pkg/encoding/bigint"
@@ -397,7 +398,7 @@ func (n *NEO) distributeGas(ic *interop.Context, h util.Uint160, acc *state.NEOB
 	if ic.Block == nil || ic.Block.Index == 0 {
 		return nil
 	}
-	gen, err := n.CalculateBonus(ic, acc.VoteTo, &acc.Balance, acc.BalanceHeight, ic.Block.Index)
+	gen, err := n.calculateBonus(ic.DAO, acc.VoteTo, &acc.Balance, acc.BalanceHeight, ic.Block.Index)
 	if err != nil {
 		return err
 	}
@@ -409,13 +410,7 @@ func (n *NEO) distributeGas(ic *interop.Context, h util.Uint160, acc *state.NEOB
 func (n *NEO) unclaimedGas(ic *interop.Context, args []stackitem.Item) stackitem.Item {
 	u := toUint160(args[0])
 	end := uint32(toBigInt(args[1]).Int64())
-	key := makeAccountKey(u)
-	si := ic.DAO.GetStorageItem(n.ContractID, key)
-	st, err := state.NEOBalanceStateFromBytes(si.Value)
-	if err != nil {
-		panic(err)
-	}
-	gen, err := n.CalculateBonus(ic, st.VoteTo, &st.Balance, st.BalanceHeight, end)
+	gen, err := n.CalculateBonus(ic.DAO, u, end)
 	if err != nil {
 		panic(err)
 	}
@@ -534,14 +529,27 @@ func makeVoterKey(pub []byte, prealloc ...[]byte) []byte {
 
 // CalculateBonus calculates amount of gas generated for holding value NEO from start to end block
 // and having voted for active committee member.
-func (n *NEO) CalculateBonus(ic *interop.Context, vote *keys.PublicKey, value *big.Int, start, end uint32) (*big.Int, error) {
-	r, err := n.CalculateNEOHolderReward(ic, value, start, end)
+func (n *NEO) CalculateBonus(d dao.DAO, acc util.Uint160, end uint32) (*big.Int, error) {
+	key := makeAccountKey(acc)
+	si := d.GetStorageItem(n.ContractID, key)
+	if si == nil {
+		return nil, storage.ErrKeyNotFound
+	}
+	st, err := state.NEOBalanceStateFromBytes(si.Value)
+	if err != nil {
+		return nil, err
+	}
+	return n.calculateBonus(d, st.VoteTo, &st.Balance, st.BalanceHeight, end)
+}
+
+func (n *NEO) calculateBonus(d dao.DAO, vote *keys.PublicKey, value *big.Int, start, end uint32) (*big.Int, error) {
+	r, err := n.CalculateNEOHolderReward(d, value, start, end)
 	if err != nil || vote == nil {
 		return r, err
 	}
 
 	var key = makeVoterKey(vote.Bytes())
-	var reward = n.getGASPerVote(ic.DAO, key, start, end)
+	var reward = n.getGASPerVote(d, key, start, end)
 	var tmp = new(big.Int).Sub(&reward[1], &reward[0])
 	tmp.Mul(tmp, value)
 	tmp.Div(tmp, big.NewInt(voterRewardFactor))
@@ -550,7 +558,7 @@ func (n *NEO) CalculateBonus(ic *interop.Context, vote *keys.PublicKey, value *b
 }
 
 // CalculateNEOHolderReward return GAS reward for holding `value` of NEO from start to end block.
-func (n *NEO) CalculateNEOHolderReward(ic *interop.Context, value *big.Int, start, end uint32) (*big.Int, error) {
+func (n *NEO) CalculateNEOHolderReward(d dao.DAO, value *big.Int, start, end uint32) (*big.Int, error) {
 	if value.Sign() == 0 || start >= end {
 		return big.NewInt(0), nil
 	} else if value.Sign() < 0 {
@@ -563,7 +571,7 @@ func (n *NEO) CalculateNEOHolderReward(ic *interop.Context, value *big.Int, star
 	if !n.gasPerBlockChanged.Load().(bool) {
 		gr = n.gasPerBlock.Load().(gasRecord)
 	} else {
-		gr, err = n.getSortedGASRecordFromDAO(ic.DAO)
+		gr, err = n.getSortedGASRecordFromDAO(d)
 		if err != nil {
 			return nil, err
 		}
diff --git a/pkg/core/native_neo_test.go b/pkg/core/native_neo_test.go
index c1e3f41ce..9601262f6 100644
--- a/pkg/core/native_neo_test.go
+++ b/pkg/core/native_neo_test.go
@@ -162,7 +162,8 @@ func TestNEO_Vote(t *testing.T) {
 			newGAS := bc.GetUtilityTokenBalance(accs[i].Contract.ScriptHash())
 			newGAS.Sub(newGAS, gasBalance[i])
 
-			gasForHold := bc.CalculateClaimable(neoBalance[i], transferBlock, bc.BlockHeight())
+			gasForHold, err := bc.contracts.NEO.CalculateNEOHolderReward(bc.dao, neoBalance[i], transferBlock, bc.BlockHeight())
+			require.NoError(t, err)
 			newGAS.Sub(newGAS, gasForHold)
 			require.True(t, newGAS.Sign() > 0)
 			gasBalance[i] = newGAS
@@ -258,11 +259,11 @@ func TestNEO_CalculateBonus(t *testing.T) {
 	ic.SpawnVM()
 	ic.VM.LoadScript([]byte{byte(opcode.RET)})
 	t.Run("Invalid", func(t *testing.T) {
-		_, err := neo.CalculateNEOHolderReward(ic, new(big.Int).SetInt64(-1), 0, 1)
+		_, err := neo.CalculateNEOHolderReward(ic.DAO, new(big.Int).SetInt64(-1), 0, 1)
 		require.Error(t, err)
 	})
 	t.Run("Zero", func(t *testing.T) {
-		res, err := neo.CalculateNEOHolderReward(ic, big.NewInt(0), 0, 100)
+		res, err := neo.CalculateNEOHolderReward(ic.DAO, big.NewInt(0), 0, 100)
 		require.NoError(t, err)
 		require.EqualValues(t, 0, res.Int64())
 	})
@@ -272,7 +273,7 @@ func TestNEO_CalculateBonus(t *testing.T) {
 		require.NoError(t, err)
 		require.True(t, ok)
 
-		res, err := neo.CalculateNEOHolderReward(ic, big.NewInt(100), 5, 15)
+		res, err := neo.CalculateNEOHolderReward(ic.DAO, big.NewInt(100), 5, 15)
 		require.NoError(t, err)
 		require.EqualValues(t, (100*5*5/10)+(100*5*1/10), res.Int64())
 
diff --git a/pkg/network/helper_test.go b/pkg/network/helper_test.go
index b8a619006..c114d5f74 100644
--- a/pkg/network/helper_test.go
+++ b/pkg/network/helper_test.go
@@ -33,7 +33,7 @@ func (chain testChain) ApplyPolicyToTxSet([]*transaction.Transaction) []*transac
 func (chain testChain) GetConfig() config.ProtocolConfiguration {
 	panic("TODO")
 }
-func (chain testChain) CalculateClaimable(*big.Int, uint32, uint32) *big.Int {
+func (chain testChain) CalculateClaimable(util.Uint160, uint32) (*big.Int, error) {
 	panic("TODO")
 }
 
diff --git a/pkg/rpc/server/server.go b/pkg/rpc/server/server.go
index bf41e54fd..65f2f7b60 100644
--- a/pkg/rpc/server/server.go
+++ b/pkg/rpc/server/server.go
@@ -951,13 +951,16 @@ func (s *Server) getUnclaimedGas(ps request.Params) (interface{}, *response.Erro
 		return nil, response.ErrInvalidParams
 	}
 
-	neo, neoHeight := s.chain.GetGoverningTokenBalance(u)
+	neo, _ := s.chain.GetGoverningTokenBalance(u)
 	if neo.Sign() == 0 {
 		return result.UnclaimedGas{
 			Address: u,
 		}, nil
 	}
-	gas := s.chain.CalculateClaimable(neo, neoHeight, s.chain.BlockHeight()+1) // +1 as in C#, for the next block.
+	gas, err := s.chain.CalculateClaimable(u, s.chain.BlockHeight()+1) // +1 as in C#, for the next block.
+	if err != nil {
+		return nil, response.NewInternalServerError("can't calculate claimable", err)
+	}
 	return result.UnclaimedGas{
 		Address:   u,
 		Unclaimed: *gas,