diff --git a/modules/core/03-connection/keeper/verify_test.go b/modules/core/03-connection/keeper/verify_test.go
index 77022015a74..f97bd12690c 100644
--- a/modules/core/03-connection/keeper/verify_test.go
+++ b/modules/core/03-connection/keeper/verify_test.go
@@ -890,6 +890,7 @@ func (suite *KeeperTestSuite) TestVerifyUpgrade() {
 			upgrade = channeltypes.NewUpgrade(
 				channeltypes.NewUpgradeFields(channeltypes.UNORDERED, []string{path.EndpointA.ConnectionID}, "v1.0.0"),
 				channeltypes.NewTimeout(clienttypes.ZeroHeight(), 100000),
+				0,
 			)
 
 			suite.chainA.GetSimApp().IBCKeeper.ChannelKeeper.SetUpgrade(suite.chainA.GetContext(), path.EndpointA.ChannelConfig.PortID, path.EndpointA.ChannelID, upgrade)
diff --git a/modules/core/04-channel/keeper/grpc_query_test.go b/modules/core/04-channel/keeper/grpc_query_test.go
index 39bb5e9c9cb..12ff1fbabbd 100644
--- a/modules/core/04-channel/keeper/grpc_query_test.go
+++ b/modules/core/04-channel/keeper/grpc_query_test.go
@@ -1863,6 +1863,7 @@ func (suite *KeeperTestSuite) TestQueryUpgrade() {
 			expectedUpgrade = types.NewUpgrade(
 				types.NewUpgradeFields(types.UNORDERED, []string{ibctesting.FirstConnectionID}, mock.Version),
 				types.NewTimeout(clienttypes.ZeroHeight(), 1000000),
+				0,
 			)
 
 			suite.chainA.GetSimApp().IBCKeeper.ChannelKeeper.SetUpgrade(suite.chainA.GetContext(), path.EndpointA.ChannelConfig.PortID, path.EndpointA.ChannelID, expectedUpgrade)
diff --git a/modules/core/04-channel/keeper/packet.go b/modules/core/04-channel/keeper/packet.go
index fd4107ee9db..087d0502d7a 100644
--- a/modules/core/04-channel/keeper/packet.go
+++ b/modules/core/04-channel/keeper/packet.go
@@ -250,7 +250,6 @@ func (k Keeper) RecvPacket(
 		// incrementing nextSequenceRecv and storing under this chain's channelEnd identifiers
 		// Since this is the receiving chain, our channelEnd is packet's destination port and channel
 		k.SetNextSequenceRecv(ctx, packet.GetDestPort(), packet.GetDestChannel(), nextSequenceRecv)
-
 	}
 
 	// log that a packet has been received & executed
diff --git a/modules/core/04-channel/keeper/packet_test.go b/modules/core/04-channel/keeper/packet_test.go
index fd5895771f3..b2af9329765 100644
--- a/modules/core/04-channel/keeper/packet_test.go
+++ b/modules/core/04-channel/keeper/packet_test.go
@@ -351,6 +351,30 @@ func (suite *KeeperTestSuite) TestRecvPacket() {
 				channel := path.EndpointB.GetChannel()
 				channel.State = types.FLUSHING
 				path.EndpointB.SetChannel(channel)
+
+				// set last packet sent sequence to sequence + 1
+				counterpartyUpgrade := types.Upgrade{LatestSequenceSend: sequence + 1}
+				path.EndpointB.SetChannelCounterpartyUpgrade(counterpartyUpgrade)
+			},
+			nil,
+		},
+		{
+			"success with an counterparty latest sequence send set to 0",
+			func() {
+				suite.coordinator.Setup(path)
+				sequence, err := path.EndpointA.SendPacket(defaultTimeoutHeight, disabledTimeoutTimestamp, ibctesting.MockPacketData)
+				suite.Require().NoError(err)
+
+				packet = types.NewPacket(ibctesting.MockPacketData, sequence, path.EndpointA.ChannelConfig.PortID, path.EndpointA.ChannelID, path.EndpointB.ChannelConfig.PortID, path.EndpointB.ChannelID, defaultTimeoutHeight, disabledTimeoutTimestamp)
+				channelCap = suite.chainB.GetChannelCapability(path.EndpointB.ChannelConfig.PortID, path.EndpointB.ChannelID)
+
+				channel := path.EndpointB.GetChannel()
+				channel.State = types.FLUSHING
+				path.EndpointB.SetChannel(channel)
+
+				// set last packet sent sequence to zero.
+				counterpartyUpgrade := types.Upgrade{LatestSequenceSend: 0}
+				path.EndpointB.SetChannelCounterpartyUpgrade(counterpartyUpgrade)
 			},
 			nil,
 		},
diff --git a/modules/core/04-channel/keeper/upgrade.go b/modules/core/04-channel/keeper/upgrade.go
index e3b9cb77d31..975cdc83bec 100644
--- a/modules/core/04-channel/keeper/upgrade.go
+++ b/modules/core/04-channel/keeper/upgrade.go
@@ -174,7 +174,7 @@ func (k Keeper) ChanUpgradeTry(
 		proofHeight, proofCounterpartyUpgrade,
 		channel.Counterparty.PortId,
 		channel.Counterparty.ChannelId,
-		types.NewUpgrade(counterpartyUpgradeFields, types.Timeout{}),
+		types.NewUpgrade(counterpartyUpgradeFields, types.Timeout{}, 0),
 	); err != nil {
 		return types.Channel{}, types.Upgrade{}, errorsmod.Wrap(err, "failed to verify counterparty upgrade")
 	}
@@ -769,6 +769,12 @@ func (k Keeper) startFlushing(ctx sdk.Context, portID, channelID string, upgrade
 	channel.State = types.FLUSHING
 	k.SetChannel(ctx, portID, channelID, channel)
 
+	nextSequenceSend, found := k.GetNextSequenceSend(ctx, portID, channelID)
+	if !found {
+		return errorsmod.Wrapf(types.ErrSequenceSendNotFound, "port ID (%s) channel ID (%s)", portID, channelID)
+	}
+
+	upgrade.LatestSequenceSend = nextSequenceSend - 1
 	upgrade.Timeout = k.getAbsoluteUpgradeTimeout(ctx)
 	k.SetUpgrade(ctx, portID, channelID, *upgrade)
 
diff --git a/modules/core/04-channel/keeper/upgrade_test.go b/modules/core/04-channel/keeper/upgrade_test.go
index 1b6ec37821c..177629d568f 100644
--- a/modules/core/04-channel/keeper/upgrade_test.go
+++ b/modules/core/04-channel/keeper/upgrade_test.go
@@ -300,7 +300,10 @@ func (suite *KeeperTestSuite) TestChanUpgradeTry() {
 				suite.Require().NoError(err)
 				suite.Require().NotEmpty(upgrade)
 				suite.Require().Equal(proposedUpgrade.Fields, upgrade.Fields)
-				suite.Require().Equal(path.EndpointA.GetChannel().UpgradeSequence, path.EndpointB.GetChannel().UpgradeSequence)
+
+				nextSequenceSend, found := path.EndpointB.Chain.GetSimApp().IBCKeeper.ChannelKeeper.GetNextSequenceSend(path.EndpointB.Chain.GetContext(), path.EndpointB.ChannelConfig.PortID, path.EndpointB.ChannelID)
+				suite.Require().True(found)
+				suite.Require().Equal(nextSequenceSend-1, upgrade.LatestSequenceSend)
 			} else {
 				suite.assertUpgradeError(err, tc.expError)
 			}
@@ -482,6 +485,14 @@ func (suite *KeeperTestSuite) TestChanUpgradeAck() {
 			},
 			commitmenttypes.ErrInvalidProof,
 		},
+		{
+			"fails due to proof verification failure, counterparty update has unexpected sequence",
+			func() {
+				// Decrementing LatestSequenceSend is sufficient to cause the proof to fail.
+				counterpartyUpgrade.LatestSequenceSend--
+			},
+			commitmenttypes.ErrInvalidProof,
+		},
 		{
 			"fails due to mismatch in upgrade ordering",
 			func() {
@@ -1824,6 +1835,15 @@ func (suite *KeeperTestSuite) TestStartFlush() {
 			},
 			connectiontypes.ErrInvalidConnectionState,
 		},
+		{
+			"next sequence send not found",
+			func() {
+				// Delete next sequence send key from store
+				store := suite.chainB.GetContext().KVStore(suite.chainB.GetSimApp().GetKey(exported.StoreKey))
+				store.Delete(host.NextSequenceSendKey(path.EndpointB.ChannelConfig.PortID, path.EndpointB.ChannelID))
+			},
+			types.ErrSequenceSendNotFound,
+		},
 	}
 
 	for _, tc := range testCases {
@@ -1857,7 +1877,12 @@ func (suite *KeeperTestSuite) TestStartFlush() {
 				suite.assertUpgradeError(err, tc.expError)
 			} else {
 				channel := path.EndpointB.GetChannel()
+
+				nextSequenceSend, ok := suite.chainB.GetSimApp().IBCKeeper.ChannelKeeper.GetNextSequenceSend(suite.chainB.GetContext(), path.EndpointB.ChannelConfig.PortID, path.EndpointB.ChannelID)
+				suite.Require().True(ok)
+
 				suite.Require().Equal(types.FLUSHING, channel.State)
+				suite.Require().Equal(nextSequenceSend-1, upgrade.LatestSequenceSend)
 
 				expectedTimeoutTimestamp := types.DefaultTimeout.Timestamp + uint64(suite.chainB.GetContext().BlockTime().UnixNano())
 				suite.Require().Equal(expectedTimeoutTimestamp, upgrade.Timeout.Timestamp)
diff --git a/modules/core/04-channel/types/msgs_test.go b/modules/core/04-channel/types/msgs_test.go
index ae8faa5a11e..5a7bec0c889 100644
--- a/modules/core/04-channel/types/msgs_test.go
+++ b/modules/core/04-channel/types/msgs_test.go
@@ -808,6 +808,7 @@ func (suite *TypesTestSuite) TestMsgChannelUpgradeAckValidateBasic() {
 			upgrade := types.NewUpgrade(
 				types.NewUpgradeFields(types.ORDERED, []string{ibctesting.FirstConnectionID}, mock.Version),
 				types.NewTimeout(clienttypes.NewHeight(1, 100), 0),
+				0,
 			)
 
 			msg = types.NewMsgChannelUpgradeAck(
@@ -834,6 +835,7 @@ func (suite *TypesTestSuite) TestMsgChannelUpgradeAckGetSigners() {
 	upgrade := types.NewUpgrade(
 		types.NewUpgradeFields(types.ORDERED, []string{ibctesting.FirstConnectionID}, mock.Version),
 		types.NewTimeout(clienttypes.NewHeight(1, 100), 0),
+		0,
 	)
 
 	msg := types.NewMsgChannelUpgradeAck(
@@ -919,6 +921,7 @@ func (suite *TypesTestSuite) TestMsgChannelUpgradeConfirmValidateBasic() {
 			counterpartyUpgrade := types.NewUpgrade(
 				types.NewUpgradeFields(types.UNORDERED, []string{ibctesting.FirstConnectionID}, mock.Version),
 				types.NewTimeout(clienttypes.NewHeight(0, 10000), timeoutTimestamp),
+				0,
 			)
 
 			msg = types.NewMsgChannelUpgradeConfirm(
diff --git a/modules/core/04-channel/types/upgrade.go b/modules/core/04-channel/types/upgrade.go
index c3a861e860b..e60fc3f624b 100644
--- a/modules/core/04-channel/types/upgrade.go
+++ b/modules/core/04-channel/types/upgrade.go
@@ -12,10 +12,11 @@ import (
 )
 
 // NewUpgrade creates a new Upgrade instance.
-func NewUpgrade(upgradeFields UpgradeFields, timeout Timeout) Upgrade {
+func NewUpgrade(upgradeFields UpgradeFields, timeout Timeout, latestPacketSent uint64) Upgrade {
 	return Upgrade{
-		Fields:  upgradeFields,
-		Timeout: timeout,
+		Fields:             upgradeFields,
+		Timeout:            timeout,
+		LatestSequenceSend: latestPacketSent,
 	}
 }
 
diff --git a/modules/core/04-channel/types/upgrade.pb.go b/modules/core/04-channel/types/upgrade.pb.go
index 5a8fca81909..7764b163ff7 100644
--- a/modules/core/04-channel/types/upgrade.pb.go
+++ b/modules/core/04-channel/types/upgrade.pb.go
@@ -25,10 +25,13 @@ const _ = proto.GoGoProtoPackageIsVersion3 // please upgrade the proto package
 
 // Upgrade is a verifiable type which contains the relevant information
 // for an attempted upgrade. It provides the proposed changes to the channel
-// end and the timeout for this upgrade attempt.
+// end, the timeout for this upgrade attempt and the latest packet sequence sent
+// which allows the counterparty to efficiently know the highest sequence it has received.
+// The latest sequence send is used for pruning and upgrading from unordered to ordered channels.
 type Upgrade struct {
-	Fields  UpgradeFields `protobuf:"bytes,1,opt,name=fields,proto3" json:"fields"`
-	Timeout Timeout       `protobuf:"bytes,2,opt,name=timeout,proto3" json:"timeout"`
+	Fields             UpgradeFields `protobuf:"bytes,1,opt,name=fields,proto3" json:"fields"`
+	Timeout            Timeout       `protobuf:"bytes,2,opt,name=timeout,proto3" json:"timeout"`
+	LatestSequenceSend uint64        `protobuf:"varint,3,opt,name=latest_sequence_send,json=latestSequenceSend,proto3" json:"latest_sequence_send,omitempty"`
 }
 
 func (m *Upgrade) Reset()         { *m = Upgrade{} }
@@ -157,31 +160,33 @@ func init() {
 func init() { proto.RegisterFile("ibc/core/channel/v1/upgrade.proto", fileDescriptor_fb1cef68588848b2) }
 
 var fileDescriptor_fb1cef68588848b2 = []byte{
-	// 378 bytes of a gzipped FileDescriptorProto
-	0x1f, 0x8b, 0x08, 0x00, 0x00, 0x00, 0x00, 0x00, 0x02, 0xff, 0x6c, 0x91, 0xcf, 0xaa, 0xd3, 0x40,
-	0x14, 0x87, 0x33, 0x6d, 0xe9, 0x9f, 0x51, 0x2b, 0x44, 0x17, 0x21, 0x48, 0x5a, 0xbb, 0xb1, 0x9b,
-	0x66, 0x6c, 0x15, 0x51, 0x71, 0x21, 0x05, 0x45, 0xdc, 0x08, 0x51, 0x37, 0x6e, 0xa4, 0x99, 0x1c,
-	0xd3, 0x81, 0x66, 0x4e, 0x9c, 0x49, 0x02, 0xbe, 0x81, 0x3b, 0xfb, 0x08, 0x3e, 0x4e, 0x97, 0x5d,
-	0xba, 0x92, 0x4b, 0xfb, 0x22, 0x97, 0x4c, 0x92, 0x5e, 0x2e, 0x64, 0x37, 0x67, 0xe6, 0xfb, 0x7d,
-	0xe7, 0x30, 0x87, 0x3e, 0x16, 0x21, 0x67, 0x1c, 0x15, 0x30, 0xbe, 0xdd, 0x48, 0x09, 0x3b, 0x56,
-	0x2c, 0x59, 0x9e, 0xc6, 0x6a, 0x13, 0x81, 0x9f, 0x2a, 0xcc, 0xd0, 0x7e, 0x20, 0x42, 0xee, 0x97,
-	0x88, 0x5f, 0x23, 0x7e, 0xb1, 0x74, 0x1f, 0xc6, 0x18, 0xa3, 0x79, 0x67, 0xe5, 0xa9, 0x42, 0xdd,
-	0x56, 0x5b, 0x93, 0x32, 0xc8, 0xec, 0x0f, 0xa1, 0x83, 0xaf, 0x95, 0xdf, 0x7e, 0x4b, 0xfb, 0x3f,
-	0x04, 0xec, 0x22, 0xed, 0x90, 0x29, 0x99, 0xdf, 0x59, 0xcd, 0xfc, 0x96, 0x56, 0x7e, 0x4d, 0xbf,
-	0x37, 0xe4, 0xba, 0x77, 0xf8, 0x3f, 0xb1, 0x82, 0x3a, 0x67, 0xbf, 0xa1, 0x83, 0x4c, 0x24, 0x80,
-	0x79, 0xe6, 0x74, 0x8c, 0xe2, 0x51, 0xab, 0xe2, 0x4b, 0xc5, 0xd4, 0xe1, 0x26, 0xf2, 0xba, 0xf7,
-	0xfb, 0xef, 0xc4, 0x9a, 0xed, 0x09, 0xbd, 0x77, 0xab, 0x87, 0xfd, 0x82, 0x0e, 0x51, 0x45, 0xa0,
-	0x84, 0x8c, 0xcd, 0x64, 0xe3, 0x95, 0xdb, 0xaa, 0xfd, 0x54, 0x42, 0xc1, 0x85, 0xb5, 0x9f, 0xd0,
-	0xfb, 0x1c, 0xa5, 0x04, 0x9e, 0x09, 0x94, 0xdf, 0xb7, 0x98, 0x6a, 0xa7, 0x33, 0xed, 0xce, 0x47,
-	0xc1, 0xf8, 0xe6, 0xfa, 0x03, 0xa6, 0xda, 0x76, 0xe8, 0xa0, 0x00, 0xa5, 0x05, 0x4a, 0xa7, 0x3b,
-	0x25, 0xf3, 0x51, 0xd0, 0x94, 0xf5, 0x48, 0x1f, 0xe9, 0xdd, 0x77, 0x4a, 0xa1, 0x0a, 0x80, 0x83,
-	0x48, 0x33, 0xdb, 0xa5, 0x43, 0x0d, 0x3f, 0x73, 0x90, 0x1c, 0xcc, 0x40, 0xbd, 0xe0, 0x52, 0x97,
-	0xae, 0x04, 0xb4, 0xde, 0xc4, 0x60, 0xbe, 0x60, 0x14, 0x34, 0x65, 0xe5, 0x5a, 0x7f, 0x3e, 0x9c,
-	0x3c, 0x72, 0x3c, 0x79, 0xe4, 0xea, 0xe4, 0x91, 0xfd, 0xd9, 0xb3, 0x8e, 0x67, 0xcf, 0xfa, 0x77,
-	0xf6, 0xac, 0x6f, 0xaf, 0x62, 0x91, 0x6d, 0xf3, 0xd0, 0xe7, 0x98, 0x30, 0x8e, 0x3a, 0x41, 0xcd,
-	0x44, 0xc8, 0x17, 0x31, 0xb2, 0xe2, 0x25, 0x4b, 0x30, 0xca, 0x77, 0xa0, 0xab, 0x6d, 0x3e, 0x7d,
-	0xbe, 0x68, 0x16, 0x9a, 0xfd, 0x4a, 0x41, 0x87, 0x7d, 0xb3, 0xcc, 0x67, 0xd7, 0x01, 0x00, 0x00,
-	0xff, 0xff, 0xf9, 0xfb, 0x1a, 0x65, 0x3f, 0x02, 0x00, 0x00,
+	// 407 bytes of a gzipped FileDescriptorProto
+	0x1f, 0x8b, 0x08, 0x00, 0x00, 0x00, 0x00, 0x00, 0x02, 0xff, 0x6c, 0x92, 0xc1, 0x6e, 0xd4, 0x30,
+	0x10, 0x86, 0xe3, 0x76, 0xd5, 0xed, 0x1a, 0x28, 0x92, 0xe9, 0x21, 0x5a, 0xa1, 0x74, 0xd9, 0x0b,
+	0x7b, 0x69, 0xdc, 0x16, 0x84, 0x00, 0x71, 0x40, 0x95, 0x40, 0x88, 0x0b, 0x92, 0x17, 0x2e, 0x5c,
+	0x56, 0x1b, 0x67, 0xc8, 0x5a, 0x4a, 0x3c, 0xc1, 0x76, 0x22, 0xf1, 0x06, 0x1c, 0xfb, 0x08, 0xbc,
+	0x0a, 0xb7, 0x1e, 0x7b, 0xe4, 0x84, 0xd0, 0xee, 0x8b, 0xa0, 0x38, 0x49, 0x11, 0x52, 0x6e, 0x99,
+	0xcc, 0xf7, 0xff, 0xfe, 0xc7, 0x63, 0xfa, 0x48, 0x25, 0x92, 0x4b, 0x34, 0xc0, 0xe5, 0x66, 0xad,
+	0x35, 0xe4, 0xbc, 0x3e, 0xe7, 0x55, 0x99, 0x99, 0x75, 0x0a, 0x71, 0x69, 0xd0, 0x21, 0x7b, 0xa0,
+	0x12, 0x19, 0x37, 0x48, 0xdc, 0x21, 0x71, 0x7d, 0x3e, 0x3d, 0xce, 0x30, 0x43, 0xdf, 0xe7, 0xcd,
+	0x57, 0x8b, 0x4e, 0x07, 0xdd, 0x7a, 0x95, 0x47, 0xe6, 0x3f, 0x09, 0x1d, 0x7f, 0x6a, 0xfd, 0xd9,
+	0x6b, 0x7a, 0xf0, 0x45, 0x41, 0x9e, 0xda, 0x90, 0xcc, 0xc8, 0xe2, 0xce, 0xc5, 0x3c, 0x1e, 0x38,
+	0x2a, 0xee, 0xe8, 0xb7, 0x9e, 0xbc, 0x1c, 0x5d, 0xff, 0x3e, 0x09, 0x44, 0xa7, 0x63, 0xaf, 0xe8,
+	0xd8, 0xa9, 0x02, 0xb0, 0x72, 0xe1, 0x9e, 0xb7, 0x78, 0x38, 0x68, 0xf1, 0xb1, 0x65, 0x3a, 0x71,
+	0x2f, 0x61, 0x67, 0xf4, 0x38, 0x5f, 0x3b, 0xb0, 0x6e, 0x65, 0xe1, 0x6b, 0x05, 0x5a, 0xc2, 0xca,
+	0x82, 0x4e, 0xc3, 0xfd, 0x19, 0x59, 0x8c, 0x04, 0x6b, 0x7b, 0xcb, 0xae, 0xb5, 0x04, 0x9d, 0xbe,
+	0x1c, 0x7d, 0xff, 0x71, 0x12, 0xcc, 0xaf, 0x08, 0xbd, 0xf7, 0x5f, 0x2a, 0xf6, 0x8c, 0x1e, 0xa2,
+	0x49, 0xc1, 0x28, 0x9d, 0xf9, 0x59, 0x8e, 0x2e, 0xa6, 0x83, 0x41, 0x3e, 0x34, 0x90, 0xb8, 0x65,
+	0xd9, 0x63, 0x7a, 0x5f, 0xa2, 0xd6, 0x20, 0x9d, 0x42, 0xbd, 0xda, 0x60, 0x69, 0xc3, 0xbd, 0xd9,
+	0xfe, 0x62, 0x22, 0x8e, 0xfe, 0xfd, 0x7e, 0x87, 0xa5, 0x65, 0x21, 0x1d, 0xd7, 0x60, 0xac, 0x42,
+	0xed, 0xd3, 0x4d, 0x44, 0x5f, 0x76, 0x91, 0xde, 0xd3, 0xbb, 0x6f, 0x8c, 0x41, 0x23, 0x40, 0x82,
+	0x2a, 0x1d, 0x9b, 0xd2, 0xc3, 0x7e, 0x26, 0x1f, 0x68, 0x24, 0x6e, 0xeb, 0xc6, 0xab, 0x00, 0x6b,
+	0xd7, 0x19, 0xf8, 0x4b, 0x9b, 0x88, 0xbe, 0x6c, 0xbd, 0x2e, 0x97, 0xd7, 0xdb, 0x88, 0xdc, 0x6c,
+	0x23, 0xf2, 0x67, 0x1b, 0x91, 0xab, 0x5d, 0x14, 0xdc, 0xec, 0xa2, 0xe0, 0xd7, 0x2e, 0x0a, 0x3e,
+	0xbf, 0xc8, 0x94, 0xdb, 0x54, 0x49, 0x2c, 0xb1, 0xe0, 0x12, 0x6d, 0x81, 0x96, 0xab, 0x44, 0x9e,
+	0x66, 0xc8, 0xeb, 0xe7, 0xbc, 0xc0, 0xb4, 0xca, 0xc1, 0xb6, 0xfb, 0x3f, 0x7b, 0x7a, 0xda, 0x3f,
+	0x01, 0xf7, 0xad, 0x04, 0x9b, 0x1c, 0xf8, 0xf5, 0x3f, 0xf9, 0x1b, 0x00, 0x00, 0xff, 0xff, 0xc0,
+	0xc7, 0xee, 0x2b, 0x71, 0x02, 0x00, 0x00,
 }
 
 func (m *Upgrade) Marshal() (dAtA []byte, err error) {
@@ -204,6 +209,11 @@ func (m *Upgrade) MarshalToSizedBuffer(dAtA []byte) (int, error) {
 	_ = i
 	var l int
 	_ = l
+	if m.LatestSequenceSend != 0 {
+		i = encodeVarintUpgrade(dAtA, i, uint64(m.LatestSequenceSend))
+		i--
+		dAtA[i] = 0x18
+	}
 	{
 		size, err := m.Timeout.MarshalToSizedBuffer(dAtA[:i])
 		if err != nil {
@@ -327,6 +337,9 @@ func (m *Upgrade) Size() (n int) {
 	n += 1 + l + sovUpgrade(uint64(l))
 	l = m.Timeout.Size()
 	n += 1 + l + sovUpgrade(uint64(l))
+	if m.LatestSequenceSend != 0 {
+		n += 1 + sovUpgrade(uint64(m.LatestSequenceSend))
+	}
 	return n
 }
 
@@ -469,6 +482,25 @@ func (m *Upgrade) Unmarshal(dAtA []byte) error {
 				return err
 			}
 			iNdEx = postIndex
+		case 3:
+			if wireType != 0 {
+				return fmt.Errorf("proto: wrong wireType = %d for field LatestSequenceSend", wireType)
+			}
+			m.LatestSequenceSend = 0
+			for shift := uint(0); ; shift += 7 {
+				if shift >= 64 {
+					return ErrIntOverflowUpgrade
+				}
+				if iNdEx >= l {
+					return io.ErrUnexpectedEOF
+				}
+				b := dAtA[iNdEx]
+				iNdEx++
+				m.LatestSequenceSend |= uint64(b&0x7F) << shift
+				if b < 0x80 {
+					break
+				}
+			}
 		default:
 			iNdEx = preIndex
 			skippy, err := skipUpgrade(dAtA[iNdEx:])
diff --git a/modules/core/04-channel/types/upgrade_test.go b/modules/core/04-channel/types/upgrade_test.go
index 2f6ce80d0c4..3bf7cf67d54 100644
--- a/modules/core/04-channel/types/upgrade_test.go
+++ b/modules/core/04-channel/types/upgrade_test.go
@@ -61,6 +61,7 @@ func (suite *TypesTestSuite) TestUpgradeValidateBasic() {
 			upgrade = types.NewUpgrade(
 				types.NewUpgradeFields(types.ORDERED, []string{ibctesting.FirstConnectionID}, mock.Version),
 				types.NewTimeout(clienttypes.NewHeight(0, 100), 0),
+				0,
 			)
 
 			tc.malleate()
diff --git a/proto/ibc/core/channel/v1/upgrade.proto b/proto/ibc/core/channel/v1/upgrade.proto
index 0b04b81eda6..294a8b8c21e 100644
--- a/proto/ibc/core/channel/v1/upgrade.proto
+++ b/proto/ibc/core/channel/v1/upgrade.proto
@@ -9,12 +9,15 @@ import "ibc/core/channel/v1/channel.proto";
 
 // Upgrade is a verifiable type which contains the relevant information
 // for an attempted upgrade. It provides the proposed changes to the channel
-// end and the timeout for this upgrade attempt.
+// end, the timeout for this upgrade attempt and the latest packet sequence sent
+// which allows the counterparty to efficiently know the highest sequence it has received. 
+// The latest sequence send is used for pruning and upgrading from unordered to ordered channels. 
 message Upgrade {
   option (gogoproto.goproto_getters) = false;
 
-  UpgradeFields fields  = 1 [(gogoproto.nullable) = false];
-  Timeout       timeout = 2 [(gogoproto.nullable) = false];
+  UpgradeFields fields               = 1 [(gogoproto.nullable) = false];
+  Timeout       timeout              = 2 [(gogoproto.nullable) = false];
+  uint64        latest_sequence_send = 3;
 }
 
 // UpgradeFields are the fields in a channel end which may be changed
diff --git a/testing/endpoint.go b/testing/endpoint.go
index 042fac27402..80e7c4dcda8 100644
--- a/testing/endpoint.go
+++ b/testing/endpoint.go
@@ -868,7 +868,8 @@ func (endpoint *Endpoint) GetProposedUpgrade() channeltypes.Upgrade {
 			ConnectionHops: []string{endpoint.ConnectionID},
 			Version:        endpoint.ChannelConfig.Version,
 		},
-		Timeout: channeltypes.NewTimeout(endpoint.Counterparty.Chain.GetTimeoutHeight(), 0),
+		Timeout:            channeltypes.NewTimeout(endpoint.Counterparty.Chain.GetTimeoutHeight(), 0),
+		LatestSequenceSend: 0,
 	}
 
 	override := endpoint.ChannelConfig.ProposedUpgrade