diff --git a/CHANGELOG.md b/CHANGELOG.md
index 0654f106245..2bc8bf64bea 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -55,6 +55,7 @@ Ref: https://keepachangelog.com/en/1.0.0/
 * [#12187](https://github.com/cosmos/cosmos-sdk/pull/12187) Add batch operation for x/nft module.
 * [#12453](https://github.com/cosmos/cosmos-sdk/pull/12453) Add `NewInMemoryWithKeyring` function which allows the creation of in memory `keystore` instances with a specified set of existing items.
 * [#11390](https://github.com/cosmos/cosmos-sdk/pull/11390) `LatestBlockResponse` & `BlockByHeightResponse` types' `Block` filed has been deprecated and they now contains new field `sdk_block` with `proposer_address` as `string`
+* [#12626](https://github.com/cosmos/cosmos-sdk/pull/12626) Upgrade IAVL to v0.19.0 with fast index and error propagation. NOTE: first start will take a while to propagate into new model.
 
 ### State Machine Breaking
 
diff --git a/UPGRADING.md b/UPGRADING.md
index b8b785ea4b5..453e7b93de8 100644
--- a/UPGRADING.md
+++ b/UPGRADING.md
@@ -70,3 +70,20 @@ Additionally, new packages have been introduced in order to further split the co
 #### PostHandler
 
 `postHandler` is like an `antehandler`, but is run _after_ the `runMsgs` execution. It is in the same store branch that `runMsgs`, meaning that both `runMsgs` and `postHandler`. This allows to run a custom logic after the execution of the messages.
+
+### IAVL
+
+v0.19.0 IAVL introduces a new "fast" index. This index represents the latest state of the
+IAVL laid out in a format that preserves data locality by key. As a result, it allows for faster queries and iterations
+since data can now be read in lexicographical order that is frequent for Cosmos-SDK chains.
+
+The first time the chain is started after the upgrade, the aforementioned index is created. The creation process
+might take time and depends on the size of the latest state of the chain. For example, Osmosis takes around 15 minutes to rebuild the index.
+
+While the index is being created, node operators can observe the following in the logs:
+"Upgrading IAVL storage for faster queries + execution on the live state. This may take a while". The store
+key is appended to the message. The message is printed for every module that has a non-transient store.
+As a result, it gives a good indication of the progress of the upgrade.
+
+There is also downgrade and re-upgrade protection. If a node operator chooses to downgrade to IAVL pre-fast index, and then upgrade again, the index is rebuilt from scratch. This implementation detail should not be relevant in most cases. It was added as a safeguard against operator
+mistakes.
diff --git a/go.mod b/go.mod
index 9e33f4d929e..f471e7855a1 100644
--- a/go.mod
+++ b/go.mod
@@ -19,7 +19,7 @@ require (
 	github.com/cosmos/cosmos-proto v1.0.0-alpha7
 	github.com/cosmos/cosmos-sdk/db v1.0.0-beta.1
 	github.com/cosmos/go-bip39 v1.0.0
-	github.com/cosmos/iavl v0.18.0
+	github.com/cosmos/iavl v0.19.0
 	github.com/cosmos/ledger-cosmos-go v0.11.1
 	github.com/desertbit/timer v0.0.0-20180107155436-c41aec40b27f // indirect
 	github.com/gogo/gateway v1.1.0
diff --git a/go.sum b/go.sum
index 5aeb1f9c50a..0e13fdea392 100644
--- a/go.sum
+++ b/go.sum
@@ -283,8 +283,8 @@ github.com/cosmos/go-bip39 v1.0.0 h1:pcomnQdrdH22njcAatO0yWojsUnCO3y2tNoV1cb6hHY
 github.com/cosmos/go-bip39 v1.0.0/go.mod h1:RNJv0H/pOIVgxw6KS7QeX2a0Uo0aKUlfhZ4xuwvCdJw=
 github.com/cosmos/gorocksdb v1.2.0 h1:d0l3jJG8M4hBouIZq0mDUHZ+zjOx044J3nGRskwTb4Y=
 github.com/cosmos/gorocksdb v1.2.0/go.mod h1:aaKvKItm514hKfNJpUJXnnOWeBnk2GL4+Qw9NHizILw=
-github.com/cosmos/iavl v0.18.0 h1:02ur4vnalMR2GuWCFNkuseUcl/BCVmg9tOeHOGiZOkE=
-github.com/cosmos/iavl v0.18.0/go.mod h1:L0VZHfq0tqMNJvXlslGExaaiZM7eSm+90Vh9QUbp6j4=
+github.com/cosmos/iavl v0.19.0 h1:sgyrjqOkycXiN7Tuupuo4QAldKFg7Sipyfeg/IL7cps=
+github.com/cosmos/iavl v0.19.0/go.mod h1:l5h9pAB3m5fihB3pXVgwYqdY8aBsMagqz7T0MUjxZeA=
 github.com/cosmos/ledger-cosmos-go v0.11.1 h1:9JIYsGnXP613pb2vPjFeMMjBI5lEDsEaF6oYorTy6J4=
 github.com/cosmos/ledger-cosmos-go v0.11.1/go.mod h1:J8//BsAGTo3OC/vDLjMRFLW6q0WAaXvHnVc7ZmE8iUY=
 github.com/cosmos/ledger-go v0.9.2 h1:Nnao/dLwaVTk1Q5U9THldpUMMXU94BOTWPddSmVB6pI=
diff --git a/store/iavl/store.go b/store/iavl/store.go
index c47e7171ad3..e8b12c47b40 100644
--- a/store/iavl/store.go
+++ b/store/iavl/store.go
@@ -9,6 +9,7 @@ import (
 	ics23 "github.com/confio/ics23/go"
 	"github.com/cosmos/iavl"
 	abci "github.com/tendermint/tendermint/abci/types"
+	"github.com/tendermint/tendermint/libs/log"
 	tmcrypto "github.com/tendermint/tendermint/proto/tendermint/crypto"
 	dbm "github.com/tendermint/tm-db"
 
@@ -42,20 +43,35 @@ type Store struct {
 // LoadStore returns an IAVL Store as a CommitKVStore. Internally, it will load the
 // store's version (id) from the provided DB. An error is returned if the version
 // fails to load, or if called with a positive version on an empty tree.
-func LoadStore(db dbm.DB, id types.CommitID, lazyLoading bool, cacheSize int) (types.CommitKVStore, error) {
-	return LoadStoreWithInitialVersion(db, id, lazyLoading, 0, cacheSize)
+func LoadStore(db dbm.DB, logger log.Logger, key types.StoreKey, id types.CommitID, lazyLoading bool, cacheSize int) (types.CommitKVStore, error) {
+	return LoadStoreWithInitialVersion(db, logger, key, id, lazyLoading, 0, cacheSize)
 }
 
 // LoadStoreWithInitialVersion returns an IAVL Store as a CommitKVStore setting its initialVersion
 // to the one given. Internally, it will load the store's version (id) from the
 // provided DB. An error is returned if the version fails to load, or if called with a positive
 // version on an empty tree.
-func LoadStoreWithInitialVersion(db dbm.DB, id types.CommitID, lazyLoading bool, initialVersion uint64, cacheSize int) (types.CommitKVStore, error) {
+func LoadStoreWithInitialVersion(db dbm.DB, logger log.Logger, key types.StoreKey, id types.CommitID, lazyLoading bool, initialVersion uint64, cacheSize int) (types.CommitKVStore, error) {
 	tree, err := iavl.NewMutableTreeWithOpts(db, cacheSize, &iavl.Options{InitialVersion: initialVersion})
 	if err != nil {
 		return nil, err
 	}
 
+	isUpgradeable, err := tree.IsUpgradeable()
+	if err != nil {
+		return nil, err
+	}
+
+	if isUpgradeable && logger != nil {
+		logger.Info(
+			"Upgrading IAVL storage for faster queries + execution on live state. This may take a while",
+			"store_key", key.String(),
+			"version", initialVersion,
+			"commit", fmt.Sprintf("%X", id),
+			"is_lazy", lazyLoading,
+		)
+	}
+
 	if lazyLoading {
 		_, err = tree.LazyLoadVersion(id.Version)
 	} else {
@@ -66,6 +82,10 @@ func LoadStoreWithInitialVersion(db dbm.DB, id types.CommitID, lazyLoading bool,
 		return nil, err
 	}
 
+	if logger != nil {
+		logger.Debug("Finished loading IAVL tree")
+	}
+
 	return &Store{
 		tree: tree,
 	}, nil
@@ -121,9 +141,14 @@ func (st *Store) Commit() types.CommitID {
 
 // LastCommitID implements Committer.
 func (st *Store) LastCommitID() types.CommitID {
+	hash, err := st.tree.Hash()
+	if err != nil {
+		panic(err)
+	}
+
 	return types.CommitID{
 		Version: st.tree.Version(),
-		Hash:    st.tree.Hash(),
+		Hash:    hash,
 	}
 }
 
@@ -179,14 +204,21 @@ func (st *Store) Set(key, value []byte) {
 // Implements types.KVStore.
 func (st *Store) Get(key []byte) []byte {
 	defer telemetry.MeasureSince(time.Now(), "store", "iavl", "get")
-	_, value := st.tree.Get(key)
+	value, err := st.tree.Get(key)
+	if err != nil {
+		panic(err)
+	}
 	return value
 }
 
 // Implements types.KVStore.
 func (st *Store) Has(key []byte) (exists bool) {
 	defer telemetry.MeasureSince(time.Now(), "store", "iavl", "has")
-	return st.tree.Has(key)
+	has, err := st.tree.Has(key)
+	if err != nil {
+		panic(err)
+	}
+	return has
 }
 
 // Implements types.KVStore.
@@ -204,30 +236,20 @@ func (st *Store) DeleteVersions(versions ...int64) error {
 
 // Implements types.KVStore.
 func (st *Store) Iterator(start, end []byte) types.Iterator {
-	var iTree *iavl.ImmutableTree
-
-	switch tree := st.tree.(type) {
-	case *immutableTree:
-		iTree = tree.ImmutableTree
-	case *iavl.MutableTree:
-		iTree = tree.ImmutableTree
+	iterator, err := st.tree.Iterator(start, end, true)
+	if err != nil {
+		panic(err)
 	}
-
-	return newIAVLIterator(iTree, start, end, true)
+	return iterator
 }
 
 // Implements types.KVStore.
 func (st *Store) ReverseIterator(start, end []byte) types.Iterator {
-	var iTree *iavl.ImmutableTree
-
-	switch tree := st.tree.(type) {
-	case *immutableTree:
-		iTree = tree.ImmutableTree
-	case *iavl.MutableTree:
-		iTree = tree.ImmutableTree
+	iterator, err := st.tree.Iterator(start, end, false)
+	if err != nil {
+		panic(err)
 	}
-
-	return newIAVLIterator(iTree, start, end, false)
+	return iterator
 }
 
 // SetInitialVersion sets the initial version of the IAVL tree. It is used when
@@ -302,7 +324,12 @@ func (st *Store) Query(req abci.RequestQuery) (res abci.ResponseQuery) {
 			break
 		}
 
-		_, res.Value = tree.GetVersioned(key, res.Height)
+		value, err := tree.GetVersioned(key, res.Height)
+		if err != nil {
+			panic(err)
+		}
+		res.Value = value
+
 		if !req.Prove {
 			break
 		}
@@ -382,7 +409,7 @@ func getProofFromTree(tree *iavl.MutableTree, key []byte, exists bool) *tmcrypto
 
 // iavlIterator implements types.Iterator.
 type iavlIterator struct {
-	*iavl.Iterator
+	dbm.Iterator
 }
 
 var _ types.Iterator = (*iavlIterator)(nil)
@@ -391,8 +418,12 @@ var _ types.Iterator = (*iavlIterator)(nil)
 // CONTRACT: Caller must release the iavlIterator, as each one creates a new
 // goroutine.
 func newIAVLIterator(tree *iavl.ImmutableTree, start, end []byte, ascending bool) *iavlIterator {
+	iterator, err := tree.Iterator(start, end, ascending)
+	if err != nil {
+		panic(err)
+	}
 	iter := &iavlIterator{
-		Iterator: tree.Iterator(start, end, ascending),
+		Iterator: iterator,
 	}
 	return iter
 }
diff --git a/store/iavl/store_test.go b/store/iavl/store_test.go
index e39a6ebee15..c70bedfd7e6 100644
--- a/store/iavl/store_test.go
+++ b/store/iavl/store_test.go
@@ -10,6 +10,7 @@ import (
 	"github.com/cosmos/iavl"
 	"github.com/stretchr/testify/require"
 	abci "github.com/tendermint/tendermint/abci/types"
+	"github.com/tendermint/tendermint/libs/log"
 	dbm "github.com/tendermint/tm-db"
 
 	"github.com/cosmos/cosmos-sdk/store/types"
@@ -58,13 +59,17 @@ func TestLoadStore(t *testing.T) {
 	store := UnsafeNewStore(tree)
 
 	// Create non-pruned height H
-	require.True(t, tree.Set([]byte("hello"), []byte("hallo")))
+	updated, err := tree.Set([]byte("hello"), []byte("hallo"))
+	require.NoError(t, err)
+	require.True(t, updated)
 	hash, verH, err := tree.SaveVersion()
 	cIDH := types.CommitID{Version: verH, Hash: hash}
 	require.Nil(t, err)
 
 	// Create pruned height Hp
-	require.True(t, tree.Set([]byte("hello"), []byte("hola")))
+	updated, err = tree.Set([]byte("hello"), []byte("hola"))
+	require.NoError(t, err)
+	require.True(t, updated)
 	hash, verHp, err := tree.SaveVersion()
 	cIDHp := types.CommitID{Version: verHp, Hash: hash}
 	require.Nil(t, err)
@@ -72,7 +77,9 @@ func TestLoadStore(t *testing.T) {
 	// TODO: Prune this height
 
 	// Create current height Hc
-	require.True(t, tree.Set([]byte("hello"), []byte("ciao")))
+	updated, err = tree.Set([]byte("hello"), []byte("ciao"))
+	require.NoError(t, err)
+	require.True(t, updated)
 	hash, verHc, err := tree.SaveVersion()
 	cIDHc := types.CommitID{Version: verHc, Hash: hash}
 	require.Nil(t, err)
@@ -93,17 +100,17 @@ func TestLoadStore(t *testing.T) {
 	require.Equal(t, string(hcStore.Get([]byte("hello"))), "ciao")
 
 	// Querying a new store at some previous non-pruned height H
-	newHStore, err := LoadStore(db, cIDH, false, DefaultIAVLCacheSize)
+	newHStore, err := LoadStore(db, log.NewNopLogger(), types.NewKVStoreKey("test"), cIDH, false, DefaultIAVLCacheSize)
 	require.NoError(t, err)
 	require.Equal(t, string(newHStore.Get([]byte("hello"))), "hallo")
 
 	// Querying a new store at some previous pruned height Hp
-	newHpStore, err := LoadStore(db, cIDHp, false, DefaultIAVLCacheSize)
+	newHpStore, err := LoadStore(db, log.NewNopLogger(), types.NewKVStoreKey("test"), cIDHp, false, DefaultIAVLCacheSize)
 	require.NoError(t, err)
 	require.Equal(t, string(newHpStore.Get([]byte("hello"))), "hola")
 
 	// Querying a new store at current height H
-	newHcStore, err := LoadStore(db, cIDHc, false, DefaultIAVLCacheSize)
+	newHcStore, err := LoadStore(db, log.NewNopLogger(), types.NewKVStoreKey("test"), cIDHc, false, DefaultIAVLCacheSize)
 	require.NoError(t, err)
 	require.Equal(t, string(newHcStore.Get([]byte("hello"))), "ciao")
 }
@@ -113,7 +120,8 @@ func TestGetImmutable(t *testing.T) {
 	tree, cID := newAlohaTree(t, db)
 	store := UnsafeNewStore(tree)
 
-	require.True(t, tree.Set([]byte("hello"), []byte("adios")))
+	updated, err := tree.Set([]byte("hello"), []byte("adios"))
+	require.True(t, updated)
 	hash, ver, err := tree.SaveVersion()
 	cID = types.CommitID{Version: ver, Hash: hash}
 	require.Nil(t, err)
diff --git a/store/iavl/tree.go b/store/iavl/tree.go
index c78782e49e3..210663a2150 100644
--- a/store/iavl/tree.go
+++ b/store/iavl/tree.go
@@ -3,6 +3,7 @@ package iavl
 import (
 	"fmt"
 
+	"github.com/cosmos/cosmos-sdk/store/types"
 	"github.com/cosmos/iavl"
 )
 
@@ -17,20 +18,21 @@ type (
 	// implemented by an iavl.MutableTree. For an immutable IAVL tree, a wrapper
 	// must be made.
 	Tree interface {
-		Has(key []byte) bool
-		Get(key []byte) (index int64, value []byte)
-		Set(key, value []byte) bool
-		Remove(key []byte) ([]byte, bool)
+		Has(key []byte) (bool, error)
+		Get(key []byte) ([]byte, error)
+		Set(key, value []byte) (bool, error)
+		Remove(key []byte) ([]byte, bool, error)
 		SaveVersion() ([]byte, int64, error)
 		DeleteVersion(version int64) error
 		DeleteVersions(versions ...int64) error
 		Version() int64
-		Hash() []byte
+		Hash() ([]byte, error)
 		VersionExists(version int64) bool
-		GetVersioned(key []byte, version int64) (int64, []byte)
+		GetVersioned(key []byte, version int64) ([]byte, error)
 		GetVersionedWithProof(key []byte, version int64) ([]byte, *iavl.RangeProof, error)
 		GetImmutable(version int64) (*iavl.ImmutableTree, error)
 		SetInitialVersion(version uint64)
+		Iterator(start, end []byte, ascending bool) (types.Iterator, error)
 		AvailableVersions() []int
 	}
 
@@ -42,11 +44,11 @@ type (
 	}
 )
 
-func (it *immutableTree) Set(_, _ []byte) bool {
+func (it *immutableTree) Set(_, _ []byte) (bool, error) {
 	panic("cannot call 'Set' on an immutable IAVL tree")
 }
 
-func (it *immutableTree) Remove(_ []byte) ([]byte, bool) {
+func (it *immutableTree) Remove(_ []byte) ([]byte, bool, error) {
 	panic("cannot call 'Remove' on an immutable IAVL tree")
 }
 
@@ -70,9 +72,9 @@ func (it *immutableTree) VersionExists(version int64) bool {
 	return it.Version() == version
 }
 
-func (it *immutableTree) GetVersioned(key []byte, version int64) (int64, []byte) {
+func (it *immutableTree) GetVersioned(key []byte, version int64) ([]byte, error) {
 	if it.Version() != version {
-		return -1, nil
+		return nil, fmt.Errorf("version mismatch on immutable IAVL tree; got: %d, expected: %d", version, it.Version())
 	}
 
 	return it.Get(key)
diff --git a/store/iavl/tree_test.go b/store/iavl/tree_test.go
index 24332b42e06..44ba844473f 100644
--- a/store/iavl/tree_test.go
+++ b/store/iavl/tree_test.go
@@ -16,10 +16,6 @@ func TestImmutableTreePanics(t *testing.T) {
 	require.Panics(t, func() { it.Remove([]byte{}) })
 	require.Panics(t, func() { it.SaveVersion() })           // nolint:errcheck
 	require.Panics(t, func() { it.DeleteVersion(int64(1)) }) // nolint:errcheck
-	v, _ := it.GetVersioned([]byte{0x01}, 1)
-	require.Equal(t, int64(-1), v)
-	v, _ = it.GetVersioned([]byte{0x01}, 0)
-	require.Equal(t, int64(0), v)
 
 	val, proof, err := it.GetVersionedWithProof(nil, 1)
 	require.Error(t, err)
diff --git a/store/rootmulti/proof_test.go b/store/rootmulti/proof_test.go
index d593732d4c6..3e5d42067d9 100644
--- a/store/rootmulti/proof_test.go
+++ b/store/rootmulti/proof_test.go
@@ -15,7 +15,7 @@ import (
 func TestVerifyIAVLStoreQueryProof(t *testing.T) {
 	// Create main tree for testing.
 	db := dbm.NewMemDB()
-	iStore, err := iavl.LoadStore(db, types.CommitID{}, false, iavl.DefaultIAVLCacheSize)
+	iStore, err := iavl.LoadStore(db, log.NewNopLogger(), types.NewKVStoreKey("test"), types.CommitID{}, false, iavl.DefaultIAVLCacheSize)
 	store := iStore.(*iavl.Store)
 	require.Nil(t, err)
 	store.Set([]byte("MYKEY"), []byte("MYVALUE"))
diff --git a/store/rootmulti/store.go b/store/rootmulti/store.go
index 7a046959f92..f44b53d5096 100644
--- a/store/rootmulti/store.go
+++ b/store/rootmulti/store.go
@@ -865,9 +865,9 @@ func (rs *Store) loadCommitStoreFromParams(key types.StoreKey, id types.CommitID
 		var err error
 
 		if params.initialVersion == 0 {
-			store, err = iavl.LoadStore(db, id, rs.lazyLoading, rs.iavlCacheSize)
+			store, err = iavl.LoadStore(db, rs.logger, key, id, rs.lazyLoading, rs.iavlCacheSize)
 		} else {
-			store, err = iavl.LoadStoreWithInitialVersion(db, id, rs.lazyLoading, params.initialVersion, rs.iavlCacheSize)
+			store, err = iavl.LoadStoreWithInitialVersion(db, rs.logger, key, id, rs.lazyLoading, params.initialVersion, rs.iavlCacheSize)
 		}
 
 		if err != nil {
diff --git a/store/tools/ics23/go.mod b/store/tools/ics23/go.mod
index a41b3567c6d..9f2e5cad106 100644
--- a/store/tools/ics23/go.mod
+++ b/store/tools/ics23/go.mod
@@ -5,7 +5,7 @@ go 1.18
 require (
 	github.com/confio/ics23/go v0.7.0
 	github.com/cosmos/cosmos-sdk v0.46.0-rc3
-	github.com/cosmos/iavl v0.18.0
+	github.com/cosmos/iavl v0.19.0
 	github.com/lazyledger/smt v0.2.1-0.20210709230900-03ea40719554
 	github.com/tendermint/tendermint v0.34.20-rc1
 	github.com/tendermint/tm-db v0.6.7
diff --git a/store/tools/ics23/iavl/cmd/testgen-iavl/main.go b/store/tools/ics23/iavl/cmd/testgen-iavl/main.go
index fe43459c9ac..615a24b513c 100644
--- a/store/tools/ics23/iavl/cmd/testgen-iavl/main.go
+++ b/store/tools/ics23/iavl/cmd/testgen-iavl/main.go
@@ -75,12 +75,12 @@ func main() {
 		fmt.Println("Usage: testgen-iavl [exist|nonexist] [left|right|middle] <size>")
 		os.Exit(1)
 	}
-	root := tree.WorkingHash()
+	root, _ := tree.WorkingHash()
 
 	var key, value []byte
 	if exist {
 		key = helpers.GetKey(allkeys, loc)
-		_, value = tree.Get(key)
+		value, _ = tree.Get(key)
 	} else {
 		key = helpers.GetNonKey(allkeys, loc)
 	}
@@ -132,14 +132,20 @@ func doBatch(args []string) error {
 	if err != nil {
 		return err
 	}
-	root := tree.WorkingHash()
+	root, err := tree.WorkingHash()
+	if err != nil {
+		return err
+	}
 
 	items := []item{}
 	proofs := []*ics23.CommitmentProof{}
 
 	for i := 0; i < exist; i++ {
 		key := []byte(helpers.GetKey(allkeys, tmproofs.Middle))
-		_, value := tree.Get(key)
+		value, err := tree.Get(key)
+		if err != nil {
+			return err
+		}
 		proof, err := iavlproofs.CreateMembershipProof(tree, key)
 		if err != nil {
 			return fmt.Errorf("create proof: %+v", err)
diff --git a/store/tools/ics23/iavl/create.go b/store/tools/ics23/iavl/create.go
index fa7020e548f..b1d04698372 100644
--- a/store/tools/ics23/iavl/create.go
+++ b/store/tools/ics23/iavl/create.go
@@ -47,18 +47,23 @@ If the key exists in the tree, this will return an error.
 */
 func CreateNonMembershipProof(tree *iavl.MutableTree, key []byte) (*ics23.CommitmentProof, error) {
 	// idx is one node right of what we want....
-	idx, val := tree.Get(key)
+	idx, val, err := tree.GetWithIndex(key)
+	if err != nil {
+		return nil, err
+	}
 	if val != nil {
 		return nil, fmt.Errorf("Cannot create NonExistanceProof when Key in State")
 	}
 
-	var err error
 	nonexist := &ics23.NonExistenceProof{
 		Key: key,
 	}
 
 	if idx >= 1 {
-		leftkey, _ := tree.GetByIndex(idx - 1)
+		leftkey, _, err := tree.GetByIndex(idx - 1)
+		if err != nil {
+			return nil, err
+		}
 		nonexist.Left, err = createExistenceProof(tree, leftkey)
 		if err != nil {
 			return nil, err
@@ -66,7 +71,10 @@ func CreateNonMembershipProof(tree *iavl.MutableTree, key []byte) (*ics23.Commit
 	}
 
 	// this will be nil if nothing right of the queried key
-	rightkey, _ := tree.GetByIndex(idx)
+	rightkey, _, err := tree.GetByIndex(idx)
+	if err != nil {
+		return nil, err
+	}
 	if rightkey != nil {
 		nonexist.Right, err = createExistenceProof(tree, rightkey)
 		if err != nil {
diff --git a/store/tools/ics23/iavl/create_test.go b/store/tools/ics23/iavl/create_test.go
index 20fd0cac310..1a1f2956161 100644
--- a/store/tools/ics23/iavl/create_test.go
+++ b/store/tools/ics23/iavl/create_test.go
@@ -29,13 +29,13 @@ func TestCreateMembership(t *testing.T) {
 				t.Fatalf("Creating tree: %+v", err)
 			}
 			key := helpers.GetKey(allkeys, tc.loc)
-			_, val := tree.Get(key)
+			val, err := tree.Get(key)
 			proof, err := CreateMembershipProof(tree, key)
 			if err != nil {
 				t.Fatalf("Creating Proof: %+v", err)
 			}
 
-			root := tree.WorkingHash()
+			root, _ := tree.WorkingHash()
 			valid := ics23.VerifyMembership(IavlSpec, root, proof, key, val)
 			if !valid {
 				t.Fatalf("Membership Proof Invalid")
@@ -70,7 +70,7 @@ func TestCreateNonMembership(t *testing.T) {
 				t.Fatalf("Creating Proof: %+v", err)
 			}
 
-			root := tree.WorkingHash()
+			root, _ := tree.WorkingHash()
 			valid := ics23.VerifyNonMembership(IavlSpec, root, proof, key)
 			if !valid {
 				t.Fatalf("Non Membership Proof Invalid")
diff --git a/store/tools/ics23/iavl/helpers/helpers.go b/store/tools/ics23/iavl/helpers/helpers.go
index 9e6c9416bdb..d552166a25b 100644
--- a/store/tools/ics23/iavl/helpers/helpers.go
+++ b/store/tools/ics23/iavl/helpers/helpers.go
@@ -45,7 +45,7 @@ func GenerateIavlResult(size int, loc tmproofs.Where) (*IavlResult, error) {
 	if len(proof.Leaves) != 1 {
 		return nil, fmt.Errorf("GetWithProof returned %d leaves", len(proof.Leaves))
 	}
-	root := tree.WorkingHash()
+	root, _ := tree.WorkingHash()
 
 	res := &IavlResult{
 		Key:      key,
diff --git a/store/types/iterator_test.go b/store/types/iterator_test.go
index 686aa112370..57b072475ea 100644
--- a/store/types/iterator_test.go
+++ b/store/types/iterator_test.go
@@ -4,6 +4,7 @@ import (
 	"testing"
 
 	"github.com/stretchr/testify/require"
+	"github.com/tendermint/tendermint/libs/log"
 	dbm "github.com/tendermint/tm-db"
 
 	"github.com/cosmos/cosmos-sdk/store/iavl"
@@ -12,7 +13,7 @@ import (
 
 func newMemTestKVStore(t *testing.T) types.KVStore {
 	db := dbm.NewMemDB()
-	store, err := iavl.LoadStore(db, types.CommitID{}, false, iavl.DefaultIAVLCacheSize)
+	store, err := iavl.LoadStore(db, log.NewNopLogger(), types.NewKVStoreKey("test"), types.CommitID{}, false, iavl.DefaultIAVLCacheSize)
 	require.NoError(t, err)
 	return store
 }