diff --git a/src/output.cpp b/src/output.cpp
index 5c6f2b677e..58f081f676 100644
--- a/src/output.cpp
+++ b/src/output.cpp
@@ -577,8 +577,7 @@ void write_tallies()
     return;
 
   // Set filename for tallies_out
-  std::string filename;
-  filename = fmt::format("{}tallies.out", settings::path_output);
+  std::string filename = fmt::format("{}tallies.out", settings::path_output);
 
   // Open the tallies.out file.
   std::ofstream tallies_out;
diff --git a/src/summary.cpp b/src/summary.cpp
index 1915fde334..b3ea0254e6 100644
--- a/src/summary.cpp
+++ b/src/summary.cpp
@@ -23,8 +23,7 @@ void write_summary()
   write_message("Writing summary.h5 file...", 5);
 
   // Set filename for summary file
-  std::string filename;
-  filename = fmt::format("{}summary.h5", settings::path_output);
+  std::string filename = fmt::format("{}summary.h5", settings::path_output);
 
   // Create a new file using default properties.
   hid_t file = file_open(filename, 'w');