diff --git a/changelogs/fragments/2454-detect_zfs_changed.yml b/changelogs/fragments/2454-detect_zfs_changed.yml
new file mode 100644
index 0000000000..0604278f6b
--- /dev/null
+++ b/changelogs/fragments/2454-detect_zfs_changed.yml
@@ -0,0 +1,2 @@
+bugfixes:
+  - zfs - certain ZFS properties, especially sizes, would lead to a task being falsely marked as "changed" even when no actual change was made (https://github.com/ansible-collections/community.general/issues/975, https://github.com/ansible-collections/community.general/pull/2454).
diff --git a/plugins/modules/storage/zfs/zfs.py b/plugins/modules/storage/zfs/zfs.py
index fe693a5045..2d5d4487dd 100644
--- a/plugins/modules/storage/zfs/zfs.py
+++ b/plugins/modules/storage/zfs/zfs.py
@@ -37,6 +37,12 @@ options:
       - A dictionary of zfs properties to be set.
       - See the zfs(8) man page for more information.
     type: dict
+notes:
+  - C(check_mode) is supported, but in certain situations it may report a task
+    as changed that will not be reported as changed when C(check_mode) is disabled.
+    For example, this might occur when the zpool C(altroot) option is set or when
+    a size is written using human-readable notation, such as C(1M) or C(1024K),
+    instead of as an unqualified byte count, such as C(1048576).
 author:
 - Johan Wiren (@johanwiren)
 '''
@@ -184,9 +190,7 @@ class Zfs(object):
             return
         cmd = [self.zfs_cmd, 'set', prop + '=' + str(value), self.name]
         (rc, out, err) = self.module.run_command(cmd)
-        if rc == 0:
-            self.changed = True
-        else:
+        if rc != 0:
             self.module.fail_json(msg=err)
 
     def set_properties_if_changed(self):
@@ -194,15 +198,25 @@ class Zfs(object):
         for prop, value in self.properties.items():
             if current_properties.get(prop, None) != value:
                 self.set_property(prop, value)
+        if self.module.check_mode:
+            return
+        updated_properties = self.get_current_properties()
+        for prop in self.properties:
+            value = updated_properties.get(prop, None)
+            if value is None:
+                self.module.fail_json(msg="zfsprop was not present after being successfully set: %s" % prop)
+            if current_properties.get(prop, None) != value:
+                self.changed = True
 
     def get_current_properties(self):
-        cmd = [self.zfs_cmd, 'get', '-H']
+        cmd = [self.zfs_cmd, 'get', '-H', '-p', '-o', "property,value,source"]
         if self.enhanced_sharing:
             cmd += ['-e']
         cmd += ['all', self.name]
         rc, out, err = self.module.run_command(" ".join(cmd))
         properties = dict()
-        for prop, value, source in [l.split('\t')[1:4] for l in out.splitlines()]:
+        for line in out.splitlines():
+            prop, value, source = line.split('\t')
             # include source '-' so that creation-only properties are not removed
             # to avoids errors when the dataset already exists and the property is not changed
             # this scenario is most likely when the same playbook is run more than once