diff --git a/src/COMPRESS/dump_atom_gz.cpp b/src/COMPRESS/dump_atom_gz.cpp
index 9be8d17b06..870bf62cd0 100644
--- a/src/COMPRESS/dump_atom_gz.cpp
+++ b/src/COMPRESS/dump_atom_gz.cpp
@@ -15,8 +15,10 @@
 #include "domain.h"
 #include "error.h"
 #include "update.h"
+#include "force.h"
 
 #include <cstring>
+#include <fmt/format.h>
 
 using namespace LAMMPS_NS;
 
@@ -25,6 +27,8 @@ DumpAtomGZ::DumpAtomGZ(LAMMPS *lmp, int narg, char **arg) :
 {
   gzFp = NULL;
 
+  compression_level = 9;
+
   if (!compressed)
     error->all(FLERR,"Dump atom/gz only writes compressed files");
 }
@@ -89,12 +93,15 @@ void DumpAtomGZ::openfile()
   // each proc with filewriter = 1 opens a file
 
   if (filewriter) {
+    std::string mode;
     if (append_flag) {
-      gzFp = gzopen(filecurrent,"ab9");
+      mode = fmt::format("ab{}", compression_level);
     } else {
-      gzFp = gzopen(filecurrent,"wb9");
+      mode = fmt::format("wb{}", compression_level);
     }
 
+    gzFp = gzopen(filecurrent, mode.c_str());
+
     if (gzFp == NULL) error->one(FLERR,"Cannot open dump file");
   } else gzFp = NULL;
 
@@ -156,3 +163,18 @@ void DumpAtomGZ::write()
   }
 }
 
+/* ---------------------------------------------------------------------- */
+
+int DumpAtomGZ::modify_param(int narg, char **arg)
+{
+  int consumed = DumpAtom::modify_param(narg, arg);
+  if(consumed == 0) {
+    if (strcmp(arg[0],"compression_level") == 0) {
+      if (narg < 2) error->all(FLERR,"Illegal dump_modify command");
+      compression_level = force->inumeric(FLERR,arg[1]);
+      if (compression_level <= 0) error->all(FLERR,"Illegal dump_modify command");
+      return 2;
+    }
+  }
+  return consumed;
+}
diff --git a/src/COMPRESS/dump_atom_gz.h b/src/COMPRESS/dump_atom_gz.h
index bd0ed792f8..0c0b95974f 100644
--- a/src/COMPRESS/dump_atom_gz.h
+++ b/src/COMPRESS/dump_atom_gz.h
@@ -31,12 +31,15 @@ class DumpAtomGZ : public DumpAtom {
   virtual ~DumpAtomGZ();
 
  protected:
+  int compression_level;
   gzFile gzFp;  // file pointer for the compressed output stream
 
   virtual void openfile();
   virtual void write_header(bigint);
   virtual void write_data(int, double *);
   virtual void write();
+
+  virtual int modify_param(int, char **);
 };
 
 }