diff --git a/CHANGELOG.md b/CHANGELOG.md
index cddbd300efd..aac15c3802d 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -11,9 +11,10 @@ We use *breaking :warning:* to mark changes that are not backward compatible (re
 ## Unreleased
 
 ### Fixed
-
+ 
 - [#7083](https://github.com/thanos-io/thanos/pull/7083) Store Gateway: Fix lazy expanded postings with 0 length failed to be cached.
 - [#7080](https://github.com/thanos-io/thanos/pull/7080) Receive: race condition in handler Close() when stopped early
+- [#7148](https://github.com/thanos-io/thanos/pull/7148) Store Gateway: Fix windows compatibility in index-header sync.
 - [#7132](https://github.com/thanos-io/thanos/pull/7132) Documentation: fix broken helm installation instruction
 
 ### Added
diff --git a/pkg/block/indexheader/binary_reader.go b/pkg/block/indexheader/binary_reader.go
index c86185bfbf8..dd68f91f73b 100644
--- a/pkg/block/indexheader/binary_reader.go
+++ b/pkg/block/indexheader/binary_reader.go
@@ -13,6 +13,7 @@ import (
 	"io"
 	"math"
 	"os"
+	"path"
 	"path/filepath"
 	"sort"
 	"sync"
@@ -112,6 +113,20 @@ func WriteBinary(ctx context.Context, bkt objstore.BucketReader, id ulid.ULID, f
 		tmpFilename = filename + ".tmp"
 	}
 
+	bw, err := writeAndClose(id, tmpFilename, indexVersion, ir)
+	if err != nil {
+		return nil, err
+	}
+
+	if tmpFilename != "" {
+		// Create index-header in atomic way, to avoid partial writes (e.g during restart or crash of store GW).
+		return nil, os.Rename(tmpFilename, filename)
+	}
+
+	return bw.Buffer(), nil
+}
+
+func writeAndClose(id ulid.ULID, tmpFilename string, indexVersion int, ir *chunkedIndexReader) (*binaryWriter, error) {
 	// Buffer for copying and encbuffers.
 	// This also will control the size of file writer buffer.
 	buf := make([]byte, 32*1024)
@@ -152,13 +167,7 @@ func WriteBinary(ctx context.Context, bkt objstore.BucketReader, id ulid.ULID, f
 	if err := bw.writer.Sync(); err != nil {
 		return nil, errors.Wrap(err, "sync")
 	}
-
-	if tmpFilename != "" {
-		// Create index-header in atomic way, to avoid partial writes (e.g during restart or crash of store GW).
-		return nil, os.Rename(tmpFilename, filename)
-	}
-
-	return bw.Buffer(), nil
+	return bw, nil
 }
 
 type chunkedIndexReader struct {
@@ -170,7 +179,7 @@ type chunkedIndexReader struct {
 }
 
 func newChunkedIndexReader(ctx context.Context, bkt objstore.BucketReader, id ulid.ULID) (*chunkedIndexReader, int, error) {
-	indexFilepath := filepath.Join(id.String(), block.IndexFilename)
+	indexFilepath := path.Join(id.String(), block.IndexFilename)
 	attrs, err := bkt.Attributes(ctx, indexFilepath)
 	if err != nil {
 		return nil, 0, errors.Wrapf(err, "get object attributes of %s", indexFilepath)
@@ -449,7 +458,8 @@ func (fw *FileWriter) Close() error {
 	if err := fw.f.Sync(); err != nil {
 		return err
 	}
-	return fw.f.Close()
+
+	return fw.Close()
 }
 
 func (fw *FileWriter) Sync() error {