diff --git a/db/c.cc b/db/c.cc
index 27a324fa1..b1c7cb21d 100644
--- a/db/c.cc
+++ b/db/c.cc
@@ -3264,6 +3264,11 @@ void rocksdb_sstfilewriter_finish(rocksdb_sstfilewriter_t* writer,
   SaveError(errptr, writer->rep->Finish(nullptr));
 }
 
+void rocksdb_sstfilewriter_file_size(rocksdb_sstfilewriter_t* writer,
+                                  uint64_t* file_size) {
+  *file_size = writer->rep->FileSize();
+}
+
 void rocksdb_sstfilewriter_destroy(rocksdb_sstfilewriter_t* writer) {
   delete writer->rep;
   delete writer;
diff --git a/include/rocksdb/c.h b/include/rocksdb/c.h
index 08e6617f9..f89f66898 100644
--- a/include/rocksdb/c.h
+++ b/include/rocksdb/c.h
@@ -1310,6 +1310,8 @@ extern ROCKSDB_LIBRARY_API void rocksdb_sstfilewriter_delete(
     char** errptr);
 extern ROCKSDB_LIBRARY_API void rocksdb_sstfilewriter_finish(
     rocksdb_sstfilewriter_t* writer, char** errptr);
+extern ROCKSDB_LIBRARY_API void rocksdb_sstfilewriter_file_size(
+    rocksdb_sstfilewriter_t* writer, uint64_t* file_size);
 extern ROCKSDB_LIBRARY_API void rocksdb_sstfilewriter_destroy(
     rocksdb_sstfilewriter_t* writer);