diff --git a/doc/src/Fortran.rst b/doc/src/Fortran.rst
index 277170eefe..bda059432f 100644
--- a/doc/src/Fortran.rst
+++ b/doc/src/Fortran.rst
@@ -1517,7 +1517,7 @@ Procedures Bound to the :f:type:`lammps` Derived Type
 
 --------
 
-.. f:function:: find_pair_neighlist(style, exact, nsub, reqid)
+.. f:function:: find_pair_neighlist(style[, exact][, nsub][, reqid])
 
    Find index of a neighbor list requested by a pair style.
 
@@ -1539,13 +1539,14 @@ Procedures Bound to the :f:type:`lammps` Derived Type
    lists and set the request ID to a value greater than zero.
 
    :p character(len=\*) style: String used to search for pair style instance.
-   :p exact: Flag to control whther style should match exactly or only a
-    regular expression/sub-string match is applied.
-   :ptype exact: logical
-   :p integer(c_int) nsub:     Match *nsub*\ th hybrid sub-style instance of
-    the same style
-   :p integer(c_int) reqid:    Request ID to identify the neighbor list in
+   :o exact: Flag to control whther style should match exactly or only a
+    regular expression/sub-string match is applied. Default: ``.TRUE.``.
+   :otype exact: logical
+   :o integer(c_int) nsub:     Match *nsub*\ th hybrid sub-style instance of
+    the same style. Default: 0.
+   :o integer(c_int) reqid:    Request ID to identify the neighbor list in
     case there are multiple requests from the same pair style instance.
+    Default: 0.
    :to: :cpp:func:`lammps_find_pair_neighlist`
    :r integer(c_int) index:    Neighbor list index if found, otherwise
     :math:`-1`.
diff --git a/fortran/lammps.f90 b/fortran/lammps.f90
index 3eb4f54762..ca065384b5 100644
--- a/fortran/lammps.f90
+++ b/fortran/lammps.f90
@@ -1857,19 +1857,30 @@ CONTAINS
       reqid)
     CLASS(lammps), INTENT(IN) :: self
     CHARACTER(LEN=*), INTENT(IN) :: style
-    LOGICAL, INTENT(IN) :: exact
-    INTEGER(c_int), INTENT(IN) :: nsub, reqid
+    LOGICAL, INTENT(IN), OPTIONAL :: exact
+    INTEGER(c_int), INTENT(IN), OPTIONAL :: nsub, reqid
     TYPE(c_ptr) :: Cstyle
-    INTEGER(c_int) :: Cexact
+    INTEGER(c_int) :: Cexact, Cnsub, Creqid
 
-    IF (exact) THEN
-      Cexact = 1_c_int
+    Cexact = 0_c_int
+    IF (PRESENT(exact)) THEN
+      IF (exact) THEN
+        Cexact = 1_c_int
+      END IF
+    END IF
+    IF (PRESENT(nsub)) THEN
+      Cnsub = nsub
     ELSE
-      Cexact = 0_c_int
+      Cnsub = 0_c_int
+    END IF
+    IF (PRESENT(reqid)) THEN
+      Creqid = reqid
+    ELSE
+      Creqid = 0_c_int
     END IF
     Cstyle = f2c_string(style)
     lmp_find_pair_neighlist = lammps_find_pair_neighlist(self%handle, Cstyle, &
-      Cexact, nsub, reqid)
+      Cexact, Cnsub, Creqid)
     IF (lmp_find_pair_neighlist < 0) THEN
       CALL lmp_error(self, LMP_ERROR_WARNING + LMP_ERROR_WORLD, &
         'unable to find pair neighbor list [Fortran/find_pair_neighlist]')