diff --git a/engine/access/rest/websockets/data_providers/send_transaction_statuses_provider.go b/engine/access/rest/websockets/data_providers/send_transaction_statuses_provider.go
index 2ccbc3c7f2a..4a661874d0e 100644
--- a/engine/access/rest/websockets/data_providers/send_transaction_statuses_provider.go
+++ b/engine/access/rest/websockets/data_providers/send_transaction_statuses_provider.go
@@ -3,19 +3,19 @@ package data_providers
 import (
 	"context"
 	"fmt"
-	"github.com/onflow/flow-go/engine/access/rest/common/parser"
-	"github.com/onflow/flow-go/engine/access/subscription"
-	"github.com/onflow/flow-go/model/flow"
-	"github.com/onflow/flow-go/module/counters"
-	"github.com/onflow/flow/protobuf/go/flow/entities"
-	"google.golang.org/grpc/codes"
-	"google.golang.org/grpc/status"
-	"strconv"
 
 	"github.com/rs/zerolog"
+	"google.golang.org/grpc/codes"
+	"google.golang.org/grpc/status"
 
 	"github.com/onflow/flow-go/access"
+	"github.com/onflow/flow-go/engine/access/rest/common/parser"
 	"github.com/onflow/flow-go/engine/access/rest/websockets/models"
+	"github.com/onflow/flow-go/engine/access/subscription"
+	"github.com/onflow/flow-go/model/flow"
+	"github.com/onflow/flow-go/module/counters"
+
+	"github.com/onflow/flow/protobuf/go/flow/entities"
 )
 
 // sendTransactionStatusesArguments contains the arguments required for sending tx and subscribing to transaction statuses
@@ -83,18 +83,18 @@ func (p *SendTransactionStatusesDataProvider) createSubscription(
 // No errors are expected during normal operations.
 func (p *SendTransactionStatusesDataProvider) handleResponse() func(txResults []*access.TransactionResult) error {
 
-	messageIndex := counters.NewMonotonousCounter(1)
+	messageIndex := counters.NewMonotonousCounter(0)
 
 	return func(txResults []*access.TransactionResult) error {
 
-		index := messageIndex.Value()
 		if ok := messageIndex.Set(messageIndex.Value() + 1); !ok {
 			return status.Errorf(codes.Internal, "message index already incremented to %d", messageIndex.Value())
 		}
+		index := messageIndex.Value()
 
 		p.send <- &models.TransactionStatusesResponse{
 			TransactionResults: txResults,
-			MessageIndex:       strconv.FormatUint(index, 10),
+			MessageIndex:       index,
 		}
 
 		return nil
diff --git a/engine/access/rest/websockets/data_providers/transaction_statuses_provider.go b/engine/access/rest/websockets/data_providers/transaction_statuses_provider.go
index c73a193da4b..7e5e993dd23 100644
--- a/engine/access/rest/websockets/data_providers/transaction_statuses_provider.go
+++ b/engine/access/rest/websockets/data_providers/transaction_statuses_provider.go
@@ -3,7 +3,6 @@ package data_providers
 import (
 	"context"
 	"fmt"
-	"strconv"
 
 	"github.com/rs/zerolog"
 	"google.golang.org/grpc/codes"
@@ -94,7 +93,7 @@ func (p *TransactionStatusesDataProvider) createSubscription(
 //
 // No errors are expected during normal operations.
 func (p *TransactionStatusesDataProvider) handleResponse() func(txResults []*access.TransactionResult) error {
-	messageIndex := counters.NewMonotonousCounter(1)
+	messageIndex := counters.NewMonotonousCounter(0)
 
 	return func(txResults []*access.TransactionResult) error {
 
@@ -105,7 +104,7 @@ func (p *TransactionStatusesDataProvider) handleResponse() func(txResults []*acc
 
 		p.send <- &models.TransactionStatusesResponse{
 			TransactionResults: txResults,
-			MessageIndex:       strconv.FormatUint(index, 10),
+			MessageIndex:       index,
 		}
 
 		return nil
diff --git a/engine/access/rest/websockets/data_providers/transaction_statuses_provider_test.go b/engine/access/rest/websockets/data_providers/transaction_statuses_provider_test.go
index 723e866ca74..11b36d14cb1 100644
--- a/engine/access/rest/websockets/data_providers/transaction_statuses_provider_test.go
+++ b/engine/access/rest/websockets/data_providers/transaction_statuses_provider_test.go
@@ -228,3 +228,82 @@ func invalidTransactionStatusesArgumentsTestCases() []testErrType {
 		},
 	}
 }
+
+// TestMessageIndexTransactionStatusesProviderResponse_HappyPath tests that MessageIndex values in response are strictly increasing.
+func (s *TransactionStatusesProviderSuite) TestMessageIndexTransactionStatusesProviderResponse_HappyPath() {
+	ctx := context.Background()
+	send := make(chan interface{}, 10)
+	topic := TransactionStatusesTopic
+	txStatusesCount := 4
+
+	// Create a channel to simulate the subscription's account statuses channel
+	txStatusesChan := make(chan interface{})
+
+	// Create a mock subscription and mock the channel
+	sub := ssmock.NewSubscription(s.T())
+	sub.On("Channel").Return((<-chan interface{})(txStatusesChan))
+	sub.On("Err").Return(nil)
+
+	s.api.On(
+		"SubscribeTransactionStatusesFromStartBlockID",
+		mock.Anything,
+		mock.Anything,
+		mock.Anything,
+		entities.EventEncodingVersion_JSON_CDC_V0,
+	).Return(sub)
+
+	arguments :=
+		map[string]interface{}{
+			"start_block_id": s.rootBlock.ID().String(),
+		}
+
+	// Create the TransactionStatusesDataProvider instance
+	provider, err := NewTransactionStatusesDataProvider(
+		ctx,
+		s.log,
+		s.api,
+		topic,
+		arguments,
+		send,
+	)
+	s.Require().NotNil(provider)
+	s.Require().NoError(err)
+
+	// Run the provider in a separate goroutine to simulate subscription processing
+	go func() {
+		err = provider.Run()
+		s.Require().NoError(err)
+	}()
+
+	// Simulate emitting data to the еч statuses channel
+	go func() {
+		defer close(txStatusesChan) // Close the channel when done
+
+		for i := 0; i < txStatusesCount; i++ {
+			txStatusesChan <- []*access.TransactionResult{}
+		}
+	}()
+
+	// Collect responses
+	var responses []*models.TransactionStatusesResponse
+	for i := 0; i < txStatusesCount; i++ {
+		res := <-send
+		txStatusesRes, ok := res.(*models.TransactionStatusesResponse)
+		s.Require().True(ok, "Expected *models.TransactionStatusesResponse, got %T", res)
+		responses = append(responses, txStatusesRes)
+	}
+
+	// Verifying that indices are starting from 0
+	s.Require().Equal(uint64(0), responses[0].MessageIndex, "Expected MessageIndex to start with 0")
+
+	// Verifying that indices are strictly increasing
+	for i := 1; i < len(responses); i++ {
+		prevIndex := responses[i-1].MessageIndex
+		currentIndex := responses[i].MessageIndex
+		s.Require().Equal(prevIndex+1, currentIndex, "Expected MessageIndex to increment by 1")
+	}
+
+	// Ensure the provider is properly closed after the test
+	provider.Close()
+
+}
diff --git a/engine/access/rest/websockets/models/tx_statuses_model.go b/engine/access/rest/websockets/models/tx_statuses_model.go
index 55b9d3bdfdd..32754a06603 100644
--- a/engine/access/rest/websockets/models/tx_statuses_model.go
+++ b/engine/access/rest/websockets/models/tx_statuses_model.go
@@ -7,5 +7,5 @@ import (
 // TransactionStatusesResponse is the response message for 'events' topic.
 type TransactionStatusesResponse struct {
 	TransactionResults []*access.TransactionResult `json:"transaction_results"`
-	MessageIndex       string                      `json:"message_index"`
+	MessageIndex       uint64                      `json:"message_index"`
 }