diff --git a/devel/trexio/trexio_file.irp.f b/devel/trexio/trexio_file.irp.f
new file mode 100644
index 0000000..c989774
--- /dev/null
+++ b/devel/trexio/trexio_file.irp.f
@@ -0,0 +1,20 @@
+BEGIN_PROVIDER [ character*(1024), trexio_filename ]
+ implicit none
+ BEGIN_DOC
+ ! Name of the TREXIO file
+ END_DOC
+ character*(1024) :: prefix
+
+ trexio_filename = trexio_file
+
+ if (trexio_file == 'None') then
+    prefix = trim(ezfio_work_dir)//trim(ezfio_filename)
+    if (backend == 0) then
+      trexio_filename = trim(prefix)//'.h5'
+    else if (backend == 1) then
+      trexio_filename = trim(prefix)
+    endif
+ endif
+END_PROVIDER
+
+