diff --git a/src/basic/env-util.c b/src/basic/env-util.c
index bf191044c0..a84863ff22 100644
--- a/src/basic/env-util.c
+++ b/src/basic/env-util.c
@@ -747,3 +747,15 @@ int getenv_bool_secure(const char *p) {
 
         return parse_boolean(e);
 }
+
+int set_unset_env(const char *name, const char *value, bool overwrite) {
+        int r;
+
+        if (value)
+                r = setenv(name, value, overwrite);
+        else
+                r = unsetenv(name);
+        if (r < 0)
+                return -errno;
+        return 0;
+}
diff --git a/src/basic/env-util.h b/src/basic/env-util.h
index a37603dbd8..6684b3350f 100644
--- a/src/basic/env-util.h
+++ b/src/basic/env-util.h
@@ -52,3 +52,6 @@ char *strv_env_get(char **x, const char *n) _pure_;
 
 int getenv_bool(const char *p);
 int getenv_bool_secure(const char *p);
+
+/* Like setenv, but calls unsetenv if value == NULL. */
+int set_unset_env(const char *name, const char *value, bool overwrite);
diff --git a/src/shared/pager.c b/src/shared/pager.c
index cd8a840e57..f689d9f28f 100644
--- a/src/shared/pager.c
+++ b/src/shared/pager.c
@@ -189,12 +189,9 @@ int pager_open(PagerFlags flags) {
 
                 /* We generally always set variables used by less, even if we end up using a different pager.
                  * They shouldn't hurt in any case, and ideally other pagers would look at them too. */
-                if (use_secure_mode)
-                        r = setenv("LESSSECURE", "1", 1);
-                else
-                        r = unsetenv("LESSSECURE");
+                r = set_unset_env("LESSSECURE", use_secure_mode ? "1" : NULL, true);
                 if (r < 0) {
-                        log_error_errno(errno, "Failed to adjust environment variable LESSSECURE: %m");
+                        log_error_errno(r, "Failed to adjust environment variable LESSSECURE: %m");
                         _exit(EXIT_FAILURE);
                 }
 
diff --git a/src/test/test-exec-util.c b/src/test/test-exec-util.c
index 5da69f7321..e9e8e21040 100644
--- a/src/test/test-exec-util.c
+++ b/src/test/test-exec-util.c
@@ -372,10 +372,7 @@ static void test_environment_gathering(void) {
         assert_se(streq(strv_env_get(env, "PATH"), DEFAULT_PATH ":/no/such/file"));
 
         /* reset environ PATH */
-        if (old)
-                (void) setenv("PATH", old, 1);
-        else
-                (void) unsetenv("PATH");
+        assert_se(set_unset_env("PATH", old, true) == 0);
 }
 
 static void test_error_catching(void) {
diff --git a/src/timedate/timedatectl.c b/src/timedate/timedatectl.c
index 455c602c30..abc792a452 100644
--- a/src/timedate/timedatectl.c
+++ b/src/timedate/timedatectl.c
@@ -12,6 +12,7 @@
 #include "bus-locator.h"
 #include "bus-map-properties.h"
 #include "bus-print-properties.h"
+#include "env-util.h"
 #include "format-table.h"
 #include "in-addr-util.h"
 #include "main-func.h"
@@ -139,12 +140,9 @@ static int print_status_info(const StatusInfo *i) {
 
 
         /* Restore the $TZ */
-        if (old_tz)
-                r = setenv("TZ", old_tz, true);
-        else
-                r = unsetenv("TZ");
+        r = set_unset_env("TZ", old_tz, true);
         if (r < 0)
-                log_warning_errno(errno, "Failed to set TZ environment variable, ignoring: %m");
+                log_warning_errno(r, "Failed to set TZ environment variable, ignoring: %m");
         else
                 tzset();