diff --git a/cli/query/query_test.go b/cli/query/query_test.go
index c85d282e0..0f7bbd4e6 100644
--- a/cli/query/query_test.go
+++ b/cli/query/query_test.go
@@ -63,7 +63,7 @@ func TestQueryTx(t *testing.T) {
 
 	_, height, err := e.Chain.GetTransaction(txHash)
 	require.NoError(t, err)
-	e.CheckNextLine(t, `BlockHash:\s+`+e.Chain.GetHeaderHash(int(height)).StringLE())
+	e.CheckNextLine(t, `BlockHash:\s+`+e.Chain.GetHeaderHash(height).StringLE())
 	e.CheckNextLine(t, `Success:\s+true`)
 	e.CheckEOF(t)
 
@@ -117,7 +117,7 @@ func compareQueryTxVerbose(t *testing.T, e *testcli.Executor, tx *transaction.Tr
 	e.CheckNextLine(t, `OnChain:\s+true`)
 	_, height, err := e.Chain.GetTransaction(tx.Hash())
 	require.NoError(t, err)
-	e.CheckNextLine(t, `BlockHash:\s+`+e.Chain.GetHeaderHash(int(height)).StringLE())
+	e.CheckNextLine(t, `BlockHash:\s+`+e.Chain.GetHeaderHash(height).StringLE())
 
 	res, _ := e.Chain.GetAppExecResults(tx.Hash(), trigger.Application)
 	e.CheckNextLine(t, fmt.Sprintf(`Success:\s+%t`, res[0].Execution.VMState == vmstate.Halt))
diff --git a/internal/fakechain/fakechain.go b/internal/fakechain/fakechain.go
index 34c1f9b6c..4ba989fdc 100644
--- a/internal/fakechain/fakechain.go
+++ b/internal/fakechain/fakechain.go
@@ -2,7 +2,6 @@ package fakechain
 
 import (
 	"errors"
-	"math"
 	"math/big"
 	"sync/atomic"
 
@@ -236,11 +235,8 @@ func (chain *FakeChain) GetNativeContractScriptHash(name string) (util.Uint160,
 }
 
 // GetHeaderHash implements the Blockchainer interface.
-func (chain *FakeChain) GetHeaderHash(n int) util.Uint256 {
-	if n < 0 || n > math.MaxUint32 {
-		return util.Uint256{}
-	}
-	return chain.hdrHashes[uint32(n)]
+func (chain *FakeChain) GetHeaderHash(n uint32) util.Uint256 {
+	return chain.hdrHashes[n]
 }
 
 // GetHeader implements the Blockchainer interface.
diff --git a/internal/testchain/address.go b/internal/testchain/address.go
index d116214fc..3db905638 100644
--- a/internal/testchain/address.go
+++ b/internal/testchain/address.go
@@ -158,7 +158,7 @@ func SignCommittee(h hash.Hashable) []byte {
 func NewBlock(t *testing.T, bc Ledger, offset uint32, primary uint32, txs ...*transaction.Transaction) *block.Block {
 	witness := transaction.Witness{VerificationScript: MultisigVerificationScript()}
 	height := bc.BlockHeight()
-	h := bc.GetHeaderHash(int(height))
+	h := bc.GetHeaderHash(height)
 	hdr, err := bc.GetHeader(h)
 	require.NoError(t, err)
 	b := &block.Block{
diff --git a/internal/testchain/transaction.go b/internal/testchain/transaction.go
index 2e05a804c..630902ac8 100644
--- a/internal/testchain/transaction.go
+++ b/internal/testchain/transaction.go
@@ -27,7 +27,7 @@ type Ledger interface {
 	FeePerByte() int64
 	GetBaseExecFee() int64
 	GetHeader(hash util.Uint256) (*block.Header, error)
-	GetHeaderHash(int) util.Uint256
+	GetHeaderHash(uint32) util.Uint256
 	HeaderHeight() uint32
 	ManagementContractHash() util.Uint160
 }
diff --git a/pkg/consensus/consensus_test.go b/pkg/consensus/consensus_test.go
index fcca5b2f5..c3f3c6098 100644
--- a/pkg/consensus/consensus_test.go
+++ b/pkg/consensus/consensus_test.go
@@ -119,7 +119,7 @@ func TestService_NextConsensus(t *testing.T) {
 	require.NoError(t, err)
 
 	checkNextConsensus := func(t *testing.T, bc *core.Blockchain, height uint32, h util.Uint160) {
-		hdrHash := bc.GetHeaderHash(int(height))
+		hdrHash := bc.GetHeaderHash(height)
 		hdr, err := bc.GetHeader(hdrHash)
 		require.NoError(t, err)
 		require.Equal(t, h, hdr.NextConsensus)
diff --git a/pkg/core/bench_test.go b/pkg/core/bench_test.go
index 2885487b7..f7d25e67d 100644
--- a/pkg/core/bench_test.go
+++ b/pkg/core/bench_test.go
@@ -109,10 +109,10 @@ func benchmarkForEachNEP17Transfer(t *testing.B, ps storage.Store, startFromBloc
 		e.CheckHalt(t, tx.Hash())
 	}
 
-	newestB, err := bc.GetBlock(bc.GetHeaderHash(int(bc.BlockHeight()) - startFromBlock + 1))
+	newestB, err := bc.GetBlock(bc.GetHeaderHash(bc.BlockHeight() - uint32(startFromBlock) + 1))
 	require.NoError(t, err)
 	newestTimestamp := newestB.Timestamp
-	oldestB, err := bc.GetBlock(bc.GetHeaderHash(int(newestB.Index) - nBlocksToTake))
+	oldestB, err := bc.GetBlock(bc.GetHeaderHash(newestB.Index - uint32(nBlocksToTake)))
 	require.NoError(t, err)
 	oldestTimestamp := oldestB.Timestamp
 
diff --git a/pkg/core/blockchain.go b/pkg/core/blockchain.go
index 43243232b..2a87a729e 100644
--- a/pkg/core/blockchain.go
+++ b/pkg/core/blockchain.go
@@ -721,7 +721,7 @@ func (bc *Blockchain) resetStateInternal(height uint32, stage stateChangeStage)
 			blocksCnt, batchCnt, keysCnt int
 		)
 		for i := height + 1; i <= currHeight; i++ {
-			err := cache.DeleteBlock(bc.GetHeaderHash(int(i)))
+			err := cache.DeleteBlock(bc.GetHeaderHash(i))
 			if err != nil {
 				return fmt.Errorf("error while removing block %d: %w", i, err)
 			}
@@ -849,7 +849,7 @@ func (bc *Blockchain) resetStateInternal(height uint32, stage stateChangeStage)
 		// Reset SYS-prefixed and IX-prefixed information.
 		bc.log.Info("trying to reset headers information")
 		for i := height + 1; i <= hHeight; i++ {
-			cache.PurgeHeader(bc.GetHeaderHash(int(i)))
+			cache.PurgeHeader(bc.GetHeaderHash(i))
 		}
 		cache.DeleteHeaderHashes(height+1, headerBatchCount)
 		cache.StoreAsCurrentBlock(b)
@@ -1174,7 +1174,7 @@ func appendTokenTransferInfo(transferData *state.TokenTransferInfo,
 func (bc *Blockchain) removeOldTransfers(index uint32) time.Duration {
 	bc.log.Info("starting transfer data garbage collection", zap.Uint32("index", index))
 	start := time.Now()
-	h, err := bc.GetHeader(bc.GetHeaderHash(int(index)))
+	h, err := bc.GetHeader(bc.GetHeaderHash(index))
 	if err != nil {
 		dur := time.Since(start)
 		bc.log.Error("failed to find block header for transfer GC", zap.Duration("time", dur), zap.Error(err))
@@ -1464,7 +1464,7 @@ func (bc *Blockchain) addHeaders(verify bool, headers ...*block.Header) error {
 		}
 
 		batch.PutCurrentHeader(lastHeader.Hash(), lastHeader.Index)
-		updateHeaderHeightMetric(len(bc.headerHashes) - 1)
+		updateHeaderHeightMetric(uint32(len(bc.headerHashes) - 1))
 		if _, err = batch.Persist(); err != nil {
 			return err
 		}
@@ -1650,7 +1650,7 @@ func (bc *Blockchain) storeBlock(block *block.Block, txpool *mempool.Pool) error
 		return fmt.Errorf("error while trying to apply MPT changes: %w", err)
 	}
 	if bc.config.StateRootInHeader && bc.HeaderHeight() > sr.Index {
-		h, err := bc.GetHeader(bc.GetHeaderHash(int(sr.Index) + 1))
+		h, err := bc.GetHeader(bc.GetHeaderHash(sr.Index + 1))
 		if err != nil {
 			err = fmt.Errorf("failed to get next header: %w", err)
 		} else if h.PrevStateRoot != sr.Root {
@@ -2174,7 +2174,7 @@ func (bc *Blockchain) CurrentBlockHash() util.Uint256 {
 		tb := topBlock.(*block.Block)
 		return tb.Hash()
 	}
-	return bc.GetHeaderHash(int(bc.BlockHeight()))
+	return bc.GetHeaderHash(bc.BlockHeight())
 }
 
 // CurrentHeaderHash returns the hash of the latest known header.
@@ -2187,11 +2187,11 @@ func (bc *Blockchain) CurrentHeaderHash() util.Uint256 {
 
 // GetHeaderHash returns hash of the header/block with specified index, if
 // Blockchain doesn't have a hash for this height, zero Uint256 value is returned.
-func (bc *Blockchain) GetHeaderHash(i int) util.Uint256 {
+func (bc *Blockchain) GetHeaderHash(i uint32) util.Uint256 {
 	bc.headerHashesLock.RLock()
 	defer bc.headerHashesLock.RUnlock()
 
-	hashesLen := len(bc.headerHashes)
+	hashesLen := uint32(len(bc.headerHashes))
 	if hashesLen <= i {
 		return util.Uint256{}
 	}
@@ -2744,7 +2744,7 @@ func (bc *Blockchain) GetTestHistoricVM(t trigger.Type, tx *transaction.Transact
 func (bc *Blockchain) getFakeNextBlock(nextBlockHeight uint32) (*block.Block, error) {
 	b := block.New(bc.config.StateRootInHeader)
 	b.Index = nextBlockHeight
-	hdr, err := bc.GetHeader(bc.GetHeaderHash(int(nextBlockHeight - 1)))
+	hdr, err := bc.GetHeader(bc.GetHeaderHash(nextBlockHeight - 1))
 	if err != nil {
 		return nil, err
 	}
diff --git a/pkg/core/blockchain_core_test.go b/pkg/core/blockchain_core_test.go
index 500b526f8..6d31d9638 100644
--- a/pkg/core/blockchain_core_test.go
+++ b/pkg/core/blockchain_core_test.go
@@ -304,7 +304,7 @@ func TestChainWithVolatileNumOfValidators(t *testing.T) {
 			},
 		}
 		curWit = nextWit
-		b.PrevHash = bc.GetHeaderHash(i - 1)
+		b.PrevHash = bc.GetHeaderHash(uint32(i) - 1)
 		b.Timestamp = uint64(time.Now().UTC().Unix())*1000 + uint64(i)
 		b.Index = uint32(i)
 		b.RebuildMerkleRoot()
diff --git a/pkg/core/blockchain_neotest_test.go b/pkg/core/blockchain_neotest_test.go
index 4cf2f8137..d1559e69c 100644
--- a/pkg/core/blockchain_neotest_test.go
+++ b/pkg/core/blockchain_neotest_test.go
@@ -1964,12 +1964,12 @@ func TestBlockchain_ResetState(t *testing.T) {
 	neoH := e.NativeHash(t, nativenames.Neo)
 	gasID := e.NativeID(t, nativenames.Gas)
 	neoID := e.NativeID(t, nativenames.Neo)
-	resetBlockHash := bc.GetHeaderHash(int(resetBlockIndex))
+	resetBlockHash := bc.GetHeaderHash(resetBlockIndex)
 	resetBlockHeader, err := bc.GetHeader(resetBlockHash)
 	require.NoError(t, err)
 	topBlockHeight := bc.BlockHeight()
-	topBH := bc.GetHeaderHash(int(bc.BlockHeight()))
-	staleBH := bc.GetHeaderHash(int(resetBlockIndex + 1))
+	topBH := bc.GetHeaderHash(bc.BlockHeight())
+	staleBH := bc.GetHeaderHash(resetBlockIndex + 1)
 	staleB, err := bc.GetBlock(staleBH)
 	require.NoError(t, err)
 	staleTx := staleB.Transactions[0]
@@ -2037,7 +2037,7 @@ func TestBlockchain_ResetState(t *testing.T) {
 	require.Equal(t, uint32(0), bc.GetStateModule().CurrentValidatedHeight())
 
 	// Try to get the latest block\header.
-	bh := bc.GetHeaderHash(int(resetBlockIndex))
+	bh := bc.GetHeaderHash(resetBlockIndex)
 	require.Equal(t, resetBlockHash, bh)
 	h, err := bc.GetHeader(bh)
 	require.NoError(t, err)
@@ -2048,7 +2048,7 @@ func TestBlockchain_ResetState(t *testing.T) {
 
 	// Check that stale blocks/headers/txs/aers/sr are not reachable.
 	for i := resetBlockIndex + 1; i <= topBlockHeight; i++ {
-		hHash := bc.GetHeaderHash(int(i))
+		hHash := bc.GetHeaderHash(i)
 		require.Equal(t, util.Uint256{}, hHash)
 		_, err = bc.GetStateRoot(i)
 		require.Error(t, err)
diff --git a/pkg/core/chaindump/dump.go b/pkg/core/chaindump/dump.go
index d2cf45469..802395591 100644
--- a/pkg/core/chaindump/dump.go
+++ b/pkg/core/chaindump/dump.go
@@ -14,14 +14,14 @@ type DumperRestorer interface {
 	AddBlock(block *block.Block) error
 	GetBlock(hash util.Uint256) (*block.Block, error)
 	GetConfig() config.ProtocolConfiguration
-	GetHeaderHash(int) util.Uint256
+	GetHeaderHash(uint32) util.Uint256
 }
 
 // Dump writes count blocks from start to the provided writer.
 // Note: header needs to be written separately by a client.
 func Dump(bc DumperRestorer, w *io.BinWriter, start, count uint32) error {
 	for i := start; i < start+count; i++ {
-		bh := bc.GetHeaderHash(int(i))
+		bh := bc.GetHeaderHash(i)
 		b, err := bc.GetBlock(bh)
 		if err != nil {
 			return err
diff --git a/pkg/core/helper_test.go b/pkg/core/helper_test.go
index 63134688a..fc74f3849 100644
--- a/pkg/core/helper_test.go
+++ b/pkg/core/helper_test.go
@@ -59,7 +59,7 @@ func (bc *Blockchain) newBlock(txs ...*transaction.Transaction) *block.Block {
 	lastBlock, ok := bc.topBlock.Load().(*block.Block)
 	if !ok {
 		var err error
-		lastBlock, err = bc.GetBlock(bc.GetHeaderHash(int(bc.BlockHeight())))
+		lastBlock, err = bc.GetBlock(bc.GetHeaderHash(bc.BlockHeight()))
 		if err != nil {
 			panic(err)
 		}
diff --git a/pkg/core/interop/context.go b/pkg/core/interop/context.go
index 85daf01ae..616ccfffd 100644
--- a/pkg/core/interop/context.go
+++ b/pkg/core/interop/context.go
@@ -40,7 +40,7 @@ type Ledger interface {
 	CurrentBlockHash() util.Uint256
 	GetBlock(hash util.Uint256) (*block.Block, error)
 	GetConfig() config.ProtocolConfiguration
-	GetHeaderHash(int) util.Uint256
+	GetHeaderHash(uint32) util.Uint256
 }
 
 // Context represents context in which interops are executed.
@@ -377,7 +377,7 @@ func (ic *Context) BlockHeight() uint32 {
 // CurrentBlockHash returns current block hash got from Context's block if it's set.
 func (ic *Context) CurrentBlockHash() util.Uint256 {
 	if ic.Block != nil {
-		return ic.Chain.GetHeaderHash(int(ic.Block.Index - 1)) // Persisting block is not yet stored.
+		return ic.Chain.GetHeaderHash(ic.Block.Index - 1) // Persisting block is not yet stored.
 	}
 	return ic.Chain.CurrentBlockHash()
 }
diff --git a/pkg/core/native/ledger.go b/pkg/core/native/ledger.go
index 708bc7e6d..51734c226 100644
--- a/pkg/core/native/ledger.go
+++ b/pkg/core/native/ledger.go
@@ -196,7 +196,7 @@ func getBlockHashFromItem(ic *interop.Context, item stackitem.Item) util.Uint256
 		if uint32(index) > ic.BlockHeight() {
 			panic(fmt.Errorf("no block with index %d", index))
 		}
-		return ic.Chain.GetHeaderHash(int(index))
+		return ic.Chain.GetHeaderHash(uint32(index))
 	}
 	hash, err := getUint256FromItem(item)
 	if err != nil {
diff --git a/pkg/core/native/native_test/ledger_test.go b/pkg/core/native/native_test/ledger_test.go
index 83455f4c5..1208aa298 100644
--- a/pkg/core/native/native_test/ledger_test.go
+++ b/pkg/core/native/native_test/ledger_test.go
@@ -111,7 +111,7 @@ func TestLedger_GetTransactionFromBlock(t *testing.T) {
 	ledgerInvoker := c.WithSigners(c.Committee)
 
 	ledgerInvoker.Invoke(t, e.Chain.BlockHeight(), "currentIndex") // Adds a block.
-	b := e.GetBlockByIndex(t, int(e.Chain.BlockHeight()))
+	b := e.GetBlockByIndex(t, e.Chain.BlockHeight())
 
 	check := func(t testing.TB, stack []stackitem.Item) {
 		require.Equal(t, 1, len(stack))
@@ -148,8 +148,8 @@ func TestLedger_GetBlock(t *testing.T) {
 	e := c.Executor
 	ledgerInvoker := c.WithSigners(c.Committee)
 
-	ledgerInvoker.Invoke(t, e.Chain.GetHeaderHash(int(e.Chain.BlockHeight())).BytesBE(), "currentHash") // Adds a block.
-	b := e.GetBlockByIndex(t, int(e.Chain.BlockHeight()))
+	ledgerInvoker.Invoke(t, e.Chain.GetHeaderHash(e.Chain.BlockHeight()).BytesBE(), "currentHash") // Adds a block.
+	b := e.GetBlockByIndex(t, e.Chain.BlockHeight())
 
 	expected := []stackitem.Item{
 		stackitem.NewByteArray(b.Hash().BytesBE()),
diff --git a/pkg/core/prometheus.go b/pkg/core/prometheus.go
index b81fb847d..f47b60e20 100644
--- a/pkg/core/prometheus.go
+++ b/pkg/core/prometheus.go
@@ -44,7 +44,7 @@ func updatePersistedHeightMetric(pHeight uint32) {
 	persistedHeight.Set(float64(pHeight))
 }
 
-func updateHeaderHeightMetric(hHeight int) {
+func updateHeaderHeightMetric(hHeight uint32) {
 	headerHeight.Set(float64(hHeight))
 }
 
diff --git a/pkg/core/statesync/module.go b/pkg/core/statesync/module.go
index 38d603e1d..58ce4c0cb 100644
--- a/pkg/core/statesync/module.go
+++ b/pkg/core/statesync/module.go
@@ -66,7 +66,7 @@ type Ledger interface {
 	BlockHeight() uint32
 	GetConfig() config.ProtocolConfiguration
 	GetHeader(hash util.Uint256) (*block.Header, error)
-	GetHeaderHash(int) util.Uint256
+	GetHeaderHash(uint32) util.Uint256
 	HeaderHeight() uint32
 }
 
@@ -214,7 +214,7 @@ func (s *Module) defineSyncStage() error {
 		s.log.Info("MPT is in sync",
 			zap.Uint32("stateroot height", s.stateMod.CurrentLocalHeight()))
 	} else if s.syncStage&headersSynced != 0 {
-		header, err := s.bc.GetHeader(s.bc.GetHeaderHash(int(s.syncPoint + 1)))
+		header, err := s.bc.GetHeader(s.bc.GetHeaderHash(s.syncPoint + 1))
 		if err != nil {
 			return fmt.Errorf("failed to get header to initialize MPT billet: %w", err)
 		}
diff --git a/pkg/core/statesync/neotest_test.go b/pkg/core/statesync/neotest_test.go
index d799d9afa..31a7a3589 100644
--- a/pkg/core/statesync/neotest_test.go
+++ b/pkg/core/statesync/neotest_test.go
@@ -16,9 +16,9 @@ import (
 )
 
 func TestStateSyncModule_Init(t *testing.T) {
-	var (
-		stateSyncInterval        = 2
-		maxTraceable      uint32 = 3
+	const (
+		stateSyncInterval = 2
+		maxTraceable      = 3
 	)
 	spoutCfg := func(c *config.ProtocolConfiguration) {
 		c.StateRootInHeader = true
@@ -55,7 +55,7 @@ func TestStateSyncModule_Init(t *testing.T) {
 
 	t.Run("inactive: bolt chain height is close enough to spout chain height", func(t *testing.T) {
 		bcBolt, _, _ := chain.NewMultiWithCustomConfig(t, boltCfg)
-		for i := 1; i < int(bcSpout.BlockHeight())-stateSyncInterval; i++ {
+		for i := uint32(1); i < bcSpout.BlockHeight()-stateSyncInterval; i++ {
 			b, err := bcSpout.GetBlock(bcSpout.GetHeaderHash(i))
 			require.NoError(t, err)
 			require.NoError(t, bcBolt.AddBlock(b))
@@ -114,9 +114,9 @@ func TestStateSyncModule_Init(t *testing.T) {
 		require.NoError(t, module.Init(bcSpout.BlockHeight()))
 
 		// firstly, fetch all headers to create proper DB state (where headers are in sync)
-		stateSyncPoint := (int(bcSpout.BlockHeight()) / stateSyncInterval) * stateSyncInterval
+		stateSyncPoint := (bcSpout.BlockHeight() / stateSyncInterval) * stateSyncInterval
 		var expectedHeader *block.Header
-		for i := 1; i <= int(bcSpout.HeaderHeight()); i++ {
+		for i := uint32(1); i <= bcSpout.HeaderHeight(); i++ {
 			header, err := bcSpout.GetHeader(bcSpout.GetHeaderHash(i))
 			require.NoError(t, err)
 			require.NoError(t, module.AddHeaders(header))
@@ -142,7 +142,7 @@ func TestStateSyncModule_Init(t *testing.T) {
 		require.Equal(t, expectedHeader.PrevStateRoot, unknownNodes[0])
 
 		// add several blocks to create DB state where blocks are not in sync yet, but it's not a genesis.
-		for i := stateSyncPoint - int(maxTraceable) + 1; i <= stateSyncPoint-stateSyncInterval-1; i++ {
+		for i := stateSyncPoint - maxTraceable + 1; i <= stateSyncPoint-stateSyncInterval-1; i++ {
 			block, err := bcSpout.GetBlock(bcSpout.GetHeaderHash(i))
 			require.NoError(t, err)
 			require.NoError(t, module.AddBlock(block))
@@ -283,10 +283,10 @@ func TestStateSyncModule_Init(t *testing.T) {
 
 func TestStateSyncModule_RestoreBasicChain(t *testing.T) {
 	check := func(t *testing.T, spoutEnableGC bool) {
-		var (
-			stateSyncInterval        = 4
-			maxTraceable      uint32 = 6
-			stateSyncPoint           = 24
+		const (
+			stateSyncInterval = 4
+			maxTraceable      = 6
+			stateSyncPoint    = 24
 		)
 		spoutCfg := func(c *config.ProtocolConfiguration) {
 			c.KeepOnlyLatestState = spoutEnableGC
@@ -325,7 +325,7 @@ func TestStateSyncModule_RestoreBasicChain(t *testing.T) {
 			require.Error(t, module.AddHeaders(h))
 		})
 		t.Run("no error: add blocks before initialisation", func(t *testing.T) {
-			b, err := bcSpout.GetBlock(bcSpout.GetHeaderHash(int(bcSpout.BlockHeight())))
+			b, err := bcSpout.GetBlock(bcSpout.GetHeaderHash(bcSpout.BlockHeight()))
 			require.NoError(t, err)
 			require.NoError(t, module.AddBlock(b))
 		})
@@ -342,7 +342,7 @@ func TestStateSyncModule_RestoreBasicChain(t *testing.T) {
 		// add headers to module
 		headers := make([]*block.Header, 0, bcSpout.HeaderHeight())
 		for i := uint32(1); i <= bcSpout.HeaderHeight(); i++ {
-			h, err := bcSpout.GetHeader(bcSpout.GetHeaderHash(int(i)))
+			h, err := bcSpout.GetHeader(bcSpout.GetHeaderHash(i))
 			require.NoError(t, err)
 			headers = append(headers, h)
 		}
@@ -355,7 +355,7 @@ func TestStateSyncModule_RestoreBasicChain(t *testing.T) {
 
 		// add blocks
 		t.Run("error: unexpected block index", func(t *testing.T) {
-			b, err := bcSpout.GetBlock(bcSpout.GetHeaderHash(stateSyncPoint - int(maxTraceable)))
+			b, err := bcSpout.GetBlock(bcSpout.GetHeaderHash(stateSyncPoint - maxTraceable))
 			require.NoError(t, err)
 			require.Error(t, module.AddBlock(b))
 		})
@@ -379,7 +379,7 @@ func TestStateSyncModule_RestoreBasicChain(t *testing.T) {
 			require.Error(t, module.AddBlock(b))
 		})
 
-		for i := stateSyncPoint - int(maxTraceable) + 1; i <= stateSyncPoint; i++ {
+		for i := uint32(stateSyncPoint - maxTraceable + 1); i <= stateSyncPoint; i++ {
 			b, err := bcSpout.GetBlock(bcSpout.GetHeaderHash(i))
 			require.NoError(t, err)
 			require.NoError(t, module.AddBlock(b))
@@ -432,7 +432,7 @@ func TestStateSyncModule_RestoreBasicChain(t *testing.T) {
 		require.Equal(t, uint32(stateSyncPoint), bcBolt.BlockHeight())
 
 		// add missing blocks to bcBolt: should be ok, because state is synced
-		for i := stateSyncPoint + 1; i <= int(bcSpout.BlockHeight()); i++ {
+		for i := uint32(stateSyncPoint + 1); i <= bcSpout.BlockHeight(); i++ {
 			b, err := bcSpout.GetBlock(bcSpout.GetHeaderHash(i))
 			require.NoError(t, err)
 			require.NoError(t, bcBolt.AddBlock(b))
diff --git a/pkg/neotest/basic.go b/pkg/neotest/basic.go
index b0653c940..8c1c5b307 100644
--- a/pkg/neotest/basic.go
+++ b/pkg/neotest/basic.go
@@ -52,7 +52,7 @@ func NewExecutor(t testing.TB, bc *core.Blockchain, validator, committee Signer)
 
 // TopBlock returns the block with the highest index.
 func (e *Executor) TopBlock(t testing.TB) *block.Block {
-	b, err := e.Chain.GetBlock(e.Chain.GetHeaderHash(int(e.Chain.BlockHeight())))
+	b, err := e.Chain.GetBlock(e.Chain.GetHeaderHash(e.Chain.BlockHeight()))
 	require.NoError(t, err)
 	return b
 }
@@ -361,7 +361,7 @@ func (e *Executor) AddBlockCheckHalt(t testing.TB, txs ...*transaction.Transacti
 
 // TestInvoke creates a test VM with a dummy block and executes a transaction in it.
 func TestInvoke(bc *core.Blockchain, tx *transaction.Transaction) (*vm.VM, error) {
-	lastBlock, err := bc.GetBlock(bc.GetHeaderHash(int(bc.BlockHeight())))
+	lastBlock, err := bc.GetBlock(bc.GetHeaderHash(bc.BlockHeight()))
 	if err != nil {
 		return nil, err
 	}
@@ -392,7 +392,7 @@ func (e *Executor) GetTransaction(t testing.TB, h util.Uint256) (*transaction.Tr
 }
 
 // GetBlockByIndex returns a block by the specified index.
-func (e *Executor) GetBlockByIndex(t testing.TB, idx int) *block.Block {
+func (e *Executor) GetBlockByIndex(t testing.TB, idx uint32) *block.Block {
 	h := e.Chain.GetHeaderHash(idx)
 	require.NotEmpty(t, h)
 	b, err := e.Chain.GetBlock(h)
diff --git a/pkg/network/server.go b/pkg/network/server.go
index 4a8512e11..11737d61b 100644
--- a/pkg/network/server.go
+++ b/pkg/network/server.go
@@ -61,7 +61,7 @@ type (
 		GetBlock(hash util.Uint256) (*block.Block, error)
 		GetConfig() config.ProtocolConfiguration
 		GetHeader(hash util.Uint256) (*block.Header, error)
-		GetHeaderHash(int) util.Uint256
+		GetHeaderHash(uint32) util.Uint256
 		GetMaxVerificationGAS() int64
 		GetMemPool() *mempool.Pool
 		GetNotaryBalance(acc util.Uint160) *big.Int
@@ -972,7 +972,7 @@ func (s *Server) handleGetBlocksCmd(p Peer, gb *payload.GetBlocks) error {
 	}
 	blockHashes := make([]util.Uint256, 0)
 	for i := start.Index + 1; i <= start.Index+uint32(count); i++ {
-		hash := s.chain.GetHeaderHash(int(i))
+		hash := s.chain.GetHeaderHash(i)
 		if hash.Equals(util.Uint256{}) {
 			break
 		}
@@ -995,7 +995,7 @@ func (s *Server) handleGetBlockByIndexCmd(p Peer, gbd *payload.GetBlockByIndex)
 		count = payload.MaxHashesCount
 	}
 	for i := gbd.IndexStart; i < gbd.IndexStart+uint32(count); i++ {
-		hash := s.chain.GetHeaderHash(int(i))
+		hash := s.chain.GetHeaderHash(i)
 		if hash.Equals(util.Uint256{}) {
 			break
 		}
@@ -1026,7 +1026,7 @@ func (s *Server) handleGetHeadersCmd(p Peer, gh *payload.GetBlockByIndex) error
 	resp := payload.Headers{}
 	resp.Hdrs = make([]*block.Header, 0, count)
 	for i := gh.IndexStart; i < gh.IndexStart+uint32(count); i++ {
-		hash := s.chain.GetHeaderHash(int(i))
+		hash := s.chain.GetHeaderHash(i)
 		if hash.Equals(util.Uint256{}) {
 			break
 		}
diff --git a/pkg/services/rpcsrv/client_test.go b/pkg/services/rpcsrv/client_test.go
index b93ac2e78..f9749d261 100644
--- a/pkg/services/rpcsrv/client_test.go
+++ b/pkg/services/rpcsrv/client_test.go
@@ -1272,7 +1272,7 @@ func TestInvokeVerify(t *testing.T) {
 	})
 
 	t.Run("positive, historic, by block, with signer", func(t *testing.T) {
-		res, err := c.InvokeContractVerifyWithState(chain.GetHeaderHash(int(chain.BlockHeight())-1), contract, []smartcontract.Parameter{}, []transaction.Signer{{Account: testchain.PrivateKeyByID(0).PublicKey().GetScriptHash()}})
+		res, err := c.InvokeContractVerifyWithState(chain.GetHeaderHash(chain.BlockHeight()-1), contract, []smartcontract.Parameter{}, []transaction.Signer{{Account: testchain.PrivateKeyByID(0).PublicKey().GetScriptHash()}})
 		require.NoError(t, err)
 		require.Equal(t, "HALT", res.State)
 		require.Equal(t, 1, len(res.Stack))
diff --git a/pkg/services/rpcsrv/server.go b/pkg/services/rpcsrv/server.go
index 349c2676e..b0dd254b4 100644
--- a/pkg/services/rpcsrv/server.go
+++ b/pkg/services/rpcsrv/server.go
@@ -78,7 +78,7 @@ type (
 		GetEnrollments() ([]state.Validator, error)
 		GetGoverningTokenBalance(acc util.Uint160) (*big.Int, uint32)
 		GetHeader(hash util.Uint256) (*block.Header, error)
-		GetHeaderHash(int) util.Uint256
+		GetHeaderHash(uint32) util.Uint256
 		GetMaxVerificationGAS() int64
 		GetMemPool() *mempool.Pool
 		GetNEP11Contracts() []util.Uint160
@@ -652,7 +652,7 @@ func (s *Server) fillBlockMetadata(obj io.Serializable, h *block.Header) result.
 		Confirmations: s.chain.BlockHeight() - h.Index + 1,
 	}
 
-	hash := s.chain.GetHeaderHash(int(h.Index) + 1)
+	hash := s.chain.GetHeaderHash(h.Index + 1)
 	if !hash.Equals(util.Uint256{}) {
 		res.NextBlockHash = &hash
 	}
@@ -1646,7 +1646,7 @@ func (s *Server) getrawtransaction(reqParams params.Params) (interface{}, *neorp
 		if height == math.MaxUint32 { // Mempooled transaction.
 			return res, nil
 		}
-		_header := s.chain.GetHeaderHash(int(height))
+		_header := s.chain.GetHeaderHash(height)
 		header, err := s.chain.GetHeader(_header)
 		if err != nil {
 			return nil, neorpc.NewRPCError("Failed to get header for the transaction", err.Error())
@@ -2037,15 +2037,12 @@ func (s *Server) getHistoricParams(reqParams params.Params) (uint32, *neorpc.Err
 			if err != nil {
 				return 0, neorpc.NewInvalidParamsError(fmt.Sprintf("unknown block or stateroot: %s", err))
 			}
-			height = int(stateH)
+			height = stateH
 		} else {
-			height = int(b.Index)
+			height = b.Index
 		}
 	}
-	if height > math.MaxUint32 {
-		return 0, neorpc.NewInvalidParamsError("historic height exceeds max uint32 value")
-	}
-	return uint32(height) + 1, nil
+	return height + 1, nil
 }
 
 func (s *Server) prepareInvocationContext(t trigger.Type, script []byte, contractScriptHash util.Uint160, tx *transaction.Transaction, nextH *uint32, verbose bool) (*interop.Context, *neorpc.Error) {
@@ -2683,16 +2680,16 @@ drainloop:
 	close(s.notaryRequestCh)
 }
 
-func (s *Server) blockHeightFromParam(param *params.Param) (int, *neorpc.Error) {
+func (s *Server) blockHeightFromParam(param *params.Param) (uint32, *neorpc.Error) {
 	num, err := param.GetInt()
 	if err != nil {
 		return 0, neorpc.ErrInvalidParams
 	}
 
-	if num < 0 || num > int(s.chain.BlockHeight()) {
+	if num < 0 || int64(num) > int64(s.chain.BlockHeight()) {
 		return 0, invalidBlockHeightError(0, num)
 	}
-	return num, nil
+	return uint32(num), nil
 }
 
 func (s *Server) packResponse(r *params.In, result interface{}, respErr *neorpc.Error) abstract {
diff --git a/pkg/services/rpcsrv/server_test.go b/pkg/services/rpcsrv/server_test.go
index ec6270e86..134dc4dd8 100644
--- a/pkg/services/rpcsrv/server_test.go
+++ b/pkg/services/rpcsrv/server_test.go
@@ -2271,7 +2271,7 @@ func testRPCProtocol(t *testing.T, doRPCCall func(string, string, *testing.T) []
 		})
 
 		t.Run("verbose != 0", func(t *testing.T) {
-			nextHash := chain.GetHeaderHash(int(hdr.Index) + 1)
+			nextHash := chain.GetHeaderHash(hdr.Index + 1)
 			expected := &result.Header{
 				Header: *hdr,
 				BlockMetadata: result.BlockMetadata{
@@ -2315,7 +2315,7 @@ func testRPCProtocol(t *testing.T, doRPCCall func(string, string, *testing.T) []
 		testNEP17T := func(t *testing.T, start, stop, limit, page int, sent, rcvd []int) {
 			ps := []string{`"` + testchain.PrivateKeyByID(0).Address() + `"`}
 			if start != 0 {
-				h, err := e.chain.GetHeader(e.chain.GetHeaderHash(start))
+				h, err := e.chain.GetHeader(e.chain.GetHeaderHash(uint32(start)))
 				var ts uint64
 				if err == nil {
 					ts = h.Timestamp
@@ -2325,7 +2325,7 @@ func testRPCProtocol(t *testing.T, doRPCCall func(string, string, *testing.T) []
 				ps = append(ps, strconv.FormatUint(ts, 10))
 			}
 			if stop != 0 {
-				h, err := e.chain.GetHeader(e.chain.GetHeaderHash(stop))
+				h, err := e.chain.GetHeader(e.chain.GetHeaderHash(uint32(stop)))
 				var ts uint64
 				if err == nil {
 					ts = h.Timestamp
@@ -2846,7 +2846,7 @@ func checkNep17TransfersAux(t *testing.T, e *executor, acc interface{}, sent, rc
 	rublesHash, err := util.Uint160DecodeStringLE(testContractHash)
 	require.NoError(t, err)
 
-	blockWithFAULTedTx, err := e.chain.GetBlock(e.chain.GetHeaderHash(int(faultedTxBlock))) // Transaction with ABORT inside.
+	blockWithFAULTedTx, err := e.chain.GetBlock(e.chain.GetHeaderHash(faultedTxBlock)) // Transaction with ABORT inside.
 	require.NoError(t, err)
 	require.Equal(t, 1, len(blockWithFAULTedTx.Transactions))
 	txFAULTed := blockWithFAULTedTx.Transactions[0]
diff --git a/scripts/gendump/main.go b/scripts/gendump/main.go
index 6f79ff917..4e7a0d309 100644
--- a/scripts/gendump/main.go
+++ b/scripts/gendump/main.go
@@ -66,7 +66,7 @@ func main() {
 	handleError("can't get next block validators", err)
 	valScript, err := smartcontract.CreateDefaultMultiSigRedeemScript(nbVals)
 	handleError("can't create verification script", err)
-	lastBlock, err := bc.GetBlock(bc.GetHeaderHash(int(bc.BlockHeight())))
+	lastBlock, err := bc.GetBlock(bc.GetHeaderHash(bc.BlockHeight()))
 	handleError("can't fetch last block", err)
 
 	txMoveNeo, err := testchain.NewTransferFromOwner(bc, bc.GoverningTokenHash(), h, native.NEOTotalSupply, 0, 2)