diff --git a/testinfra/modules/service.py b/testinfra/modules/service.py
index 830d066d..592558b5 100644
--- a/testinfra/modules/service.py
+++ b/testinfra/modules/service.py
@@ -143,6 +143,32 @@ def is_enabled(self):
 
 
 class SystemdService(SysvService):
+    suffix_list = [
+        "service",
+        "socket",
+        "device",
+        "mount",
+        "automount",
+        "swap",
+        "target",
+        "path",
+        "timer",
+        "slice",
+        "scope",
+    ]
+    """
+    List of valid suffixes for systemd unit files
+
+    See systemd.unit(5) for more details
+    """
+
+    def _has_systemd_suffix(self):
+        """
+        Check if service name has a known systemd unit suffix
+        """
+        unit_suffix = self.name.split(".")[-1]
+        return unit_suffix in self.suffix_list
+
     @property
     def is_running(self):
         out = self.run_expect([0, 1, 3], "systemctl is-active %s", self.name)
@@ -158,14 +184,20 @@ def is_enabled(self):
             return True
         if cmd.stdout.strip() == "disabled":
             return False
-        # Fallback on SysV
+        # Fallback on SysV - only for non-systemd units
         # https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=760616
-        return super().is_enabled
+        if not self._has_systemd_suffix():
+            return super().is_enabled
+        raise RuntimeError(
+            "Unable to determine state of {0}. Does this service exist?".format(
+                self.name
+            )
+        )
 
     @property
     def is_valid(self):
-        # systemd-analyze requires a full path.
-        if self.name.endswith(".service"):
+        # systemd-analyze requires a full unit name.
+        if self._has_systemd_suffix():
             name = self.name
         else:
             name = self.name + ".service"
@@ -264,9 +296,7 @@ def is_enabled(self):
         if self.name in self.check_output("rcctl ls off").splitlines():
             return False
         raise RuntimeError(
-            "Unable to determine state of {0}. Does this service exist?".format(
-                self.name
-            )
+            f"Unable to determine state of {self.name}. Does this service exist?"
         )