diff --git a/src/basic/env-util.c b/src/basic/env-util.c
index 7964a368db..4f6240e546 100644
--- a/src/basic/env-util.c
+++ b/src/basic/env-util.c
@@ -19,7 +19,7 @@
 
 /* We follow bash for the character set. Different shells have different rules. */
 #define VALID_BASH_ENV_NAME_CHARS               \
-        DIGITS LETTERS                          \
+        ALPHANUMERICAL                          \
         "_"
 
 size_t sc_arg_max(void) {
diff --git a/src/basic/login-util.c b/src/basic/login-util.c
index 926e482fb0..7f9b84be3c 100644
--- a/src/basic/login-util.c
+++ b/src/basic/login-util.c
@@ -10,7 +10,7 @@ bool session_id_valid(const char *id) {
         if (isempty(id))
                 return false;
 
-        return id[strspn(id, LETTERS DIGITS)] == '\0';
+        return in_charset(id, ALPHANUMERICAL);
 }
 
 bool logind_running(void) {
diff --git a/src/basic/unit-name.c b/src/basic/unit-name.c
index 43b3f68312..8a04638b2f 100644
--- a/src/basic/unit-name.c
+++ b/src/basic/unit-name.c
@@ -17,8 +17,7 @@
 
 /* Characters valid in a unit name. */
 #define VALID_CHARS                             \
-        DIGITS                                  \
-        LETTERS                                 \
+        ALPHANUMERICAL                          \
         ":-_.\\"
 
 /* The same, but also permits the single @ character that may appear */
diff --git a/src/hostname/hostnamed.c b/src/hostname/hostnamed.c
index a567221f8e..04c72e8137 100644
--- a/src/hostname/hostnamed.c
+++ b/src/hostname/hostnamed.c
@@ -49,7 +49,7 @@
 #include "varlink-util.h"
 #include "virt.h"
 
-#define VALID_DEPLOYMENT_CHARS (DIGITS LETTERS "-.:")
+#define VALID_DEPLOYMENT_CHARS (ALPHANUMERICAL "-.:")
 
 /* Properties we cache are indexed by an enum, to make invalidation easy and systematic (as we can iterate
  * through them all, and they are uniformly strings). */
diff --git a/src/import/oci-util.c b/src/import/oci-util.c
index 37a617b28c..96f7729fb6 100644
--- a/src/import/oci-util.c
+++ b/src/import/oci-util.c
@@ -79,10 +79,10 @@ bool oci_tag_is_valid(const char *n) {
          * [a-zA-Z0-9_][a-zA-Z0-9._-]{0,127}
          */
 
-        if (!strchr(LETTERS DIGITS "_", n[0]))
+        if (!strchr(ALPHANUMERICAL "_", n[0]))
                 return false;
 
-        size_t l = strspn(n + 1, LETTERS DIGITS "._-");
+        size_t l = strspn(n + 1, ALPHANUMERICAL "._-");
         if (l > 126)
                 return false;
         if (n[1+l] != 0)
@@ -387,7 +387,7 @@ char* urlescape(const char *s) {
 
         char *p = t;
         for (; s && *s; s++) {
-                if (strchr(LETTERS DIGITS ".-_", *s))
+                if (strchr(ALPHANUMERICAL ".-_", *s))
                         *(p++) = *s;
                 else {
                         *(p++) = '%';
diff --git a/src/portable/portablectl.c b/src/portable/portablectl.c
index dfe6df3bf3..d277504a81 100644
--- a/src/portable/portablectl.c
+++ b/src/portable/portablectl.c
@@ -155,7 +155,7 @@ static int extract_prefix(const char *path, char **ret) {
 
         /* A slightly reduced version of what's permitted in unit names. With ':' and '\' are removed, as well as '_'
          * which we use as delimiter for the second part of the image string, which we ignore for now. */
-        if (!in_charset(name, DIGITS LETTERS "-."))
+        if (!in_charset(name, ALPHANUMERICAL "-."))
                 return -EINVAL;
 
         if (!filename_is_valid(name))