diff --git a/lib/api/model/events.dart b/lib/api/model/events.dart
index 9fd83c88f4..e095c5360b 100644
--- a/lib/api/model/events.dart
+++ b/lib/api/model/events.dart
@@ -71,6 +71,13 @@ sealed class Event {
           case 'peer_remove': return SubscriptionPeerRemoveEvent.fromJson(json);
           default: return UnexpectedEvent.fromJson(json);
         }
+      case 'channel_folder':
+        switch (json['op'] as String) {
+          case 'add': return ChannelFolderAddEvent.fromJson(json);
+          case 'reorder': return ChannelFolderReorderEvent.fromJson(json);
+          case 'update': return ChannelFolderUpdateEvent.fromJson(json);
+          default: return UnexpectedEvent.fromJson(json);
+        }
       case 'user_status': return UserStatusEvent.fromJson(json);
       case 'user_topic': return UserTopicEvent.fromJson(json);
       case 'muted_users': return MutedUsersEvent.fromJson(json);
@@ -676,6 +683,8 @@ class ChannelUpdateEvent extends ChannelEvent {
         return value as int?;
       case ChannelPropertyName.channelPostPolicy:
         return ChannelPostPolicy.fromApiValue(value as int);
+      case ChannelPropertyName.folderId:
+        return value as int?;
       case ChannelPropertyName.canAddSubscribersGroup:
       case ChannelPropertyName.canDeleteAnyMessageGroup:
       case ChannelPropertyName.canDeleteOwnMessageGroup:
@@ -885,6 +894,103 @@ class SubscriptionPeerRemoveEvent extends SubscriptionEvent {
   Map<String, dynamic> toJson() => _$SubscriptionPeerRemoveEventToJson(this);
 }
 
+/// A Zulip event of type `channel_folder`.
+///
+/// The corresponding API docs are in several places for
+/// different values of `op`; see subclasses.
+sealed class ChannelFolderEvent extends Event {
+  @override
+  @JsonKey(includeToJson: true)
+  String get type => 'channel_folder';
+
+  String get op;
+
+  ChannelFolderEvent({required super.id});
+}
+
+/// A [ChannelFolderEvent] with op `add`:
+///   https://zulip.com/api/get-events#channel_folder-add
+@JsonSerializable(fieldRename: FieldRename.snake)
+class ChannelFolderAddEvent extends ChannelFolderEvent {
+  @override
+  @JsonKey(includeToJson: true)
+  String get op => 'add';
+
+  final ChannelFolder channelFolder;
+
+  ChannelFolderAddEvent({required super.id, required this.channelFolder});
+
+  factory ChannelFolderAddEvent.fromJson(Map<String, dynamic> json) =>
+    _$ChannelFolderAddEventFromJson(json);
+
+  @override
+  Map<String, dynamic> toJson() => _$ChannelFolderAddEventToJson(this);
+}
+
+/// A [ChannelFolderEvent] with op `update`:
+///   https://zulip.com/api/get-events#channel_folder-update
+@JsonSerializable(fieldRename: FieldRename.snake)
+class ChannelFolderUpdateEvent extends ChannelFolderEvent {
+  @override
+  @JsonKey(includeToJson: true)
+  String get op => 'update';
+
+  final int channelFolderId;
+  final ChannelFolderChange data;
+
+  ChannelFolderUpdateEvent({
+    required super.id,
+    required this.channelFolderId,
+    required this.data,
+  });
+
+  factory ChannelFolderUpdateEvent.fromJson(Map<String, dynamic> json) =>
+    _$ChannelFolderUpdateEventFromJson(json);
+
+  @override
+  Map<String, dynamic> toJson() => _$ChannelFolderUpdateEventToJson(this);
+}
+
+/// Details of a channel-folder change, as in [ChannelFolderUpdateEvent.data].
+@JsonSerializable(fieldRename: FieldRename.snake)
+class ChannelFolderChange {
+  final String? name;
+  final String? description;
+  final String? renderedDescription;
+  final bool? isArchived;
+
+  ChannelFolderChange({
+    required this.name,
+    required this.description,
+    required this.renderedDescription,
+    required this.isArchived,
+  });
+
+  factory ChannelFolderChange.fromJson(Map<String, dynamic> json) =>
+    _$ChannelFolderChangeFromJson(json);
+
+  Map<String, dynamic> toJson() => _$ChannelFolderChangeToJson(this);
+}
+
+/// A [ChannelFolderEvent] with op `update`:
+///   https://zulip.com/api/get-events#channel_folder-update
+@JsonSerializable(fieldRename: FieldRename.snake)
+class ChannelFolderReorderEvent extends ChannelFolderEvent {
+  @override
+  @JsonKey(includeToJson: true)
+  String get op => 'reorder';
+
+  final List<int> order;
+
+  ChannelFolderReorderEvent({required super.id, required this.order});
+
+  factory ChannelFolderReorderEvent.fromJson(Map<String, dynamic> json) =>
+    _$ChannelFolderReorderEventFromJson(json);
+
+  @override
+  Map<String, dynamic> toJson() => _$ChannelFolderReorderEventToJson(this);
+}
+
 /// A Zulip event of type `user_status`: https://zulip.com/api/get-events#user_status
 @JsonSerializable(fieldRename: FieldRename.snake, createToJson: false)
 class UserStatusEvent extends Event {
diff --git a/lib/api/model/events.g.dart b/lib/api/model/events.g.dart
index 7bf9ef0fcd..dff0d21fa2 100644
--- a/lib/api/model/events.g.dart
+++ b/lib/api/model/events.g.dart
@@ -462,6 +462,7 @@ const _$ChannelPropertyNameEnumMap = {
   ChannelPropertyName.inviteOnly: 'invite_only',
   ChannelPropertyName.messageRetentionDays: 'message_retention_days',
   ChannelPropertyName.channelPostPolicy: 'stream_post_policy',
+  ChannelPropertyName.folderId: 'folder_id',
   ChannelPropertyName.canAddSubscribersGroup: 'can_add_subscribers_group',
   ChannelPropertyName.canDeleteAnyMessageGroup: 'can_delete_any_message_group',
   ChannelPropertyName.canDeleteOwnMessageGroup: 'can_delete_own_message_group',
@@ -588,6 +589,77 @@ Map<String, dynamic> _$SubscriptionPeerRemoveEventToJson(
   'user_ids': instance.userIds,
 };
 
+ChannelFolderAddEvent _$ChannelFolderAddEventFromJson(
+  Map<String, dynamic> json,
+) => ChannelFolderAddEvent(
+  id: (json['id'] as num).toInt(),
+  channelFolder: ChannelFolder.fromJson(
+    json['channel_folder'] as Map<String, dynamic>,
+  ),
+);
+
+Map<String, dynamic> _$ChannelFolderAddEventToJson(
+  ChannelFolderAddEvent instance,
+) => <String, dynamic>{
+  'id': instance.id,
+  'type': instance.type,
+  'op': instance.op,
+  'channel_folder': instance.channelFolder,
+};
+
+ChannelFolderUpdateEvent _$ChannelFolderUpdateEventFromJson(
+  Map<String, dynamic> json,
+) => ChannelFolderUpdateEvent(
+  id: (json['id'] as num).toInt(),
+  channelFolderId: (json['channel_folder_id'] as num).toInt(),
+  data: ChannelFolderChange.fromJson(json['data'] as Map<String, dynamic>),
+);
+
+Map<String, dynamic> _$ChannelFolderUpdateEventToJson(
+  ChannelFolderUpdateEvent instance,
+) => <String, dynamic>{
+  'id': instance.id,
+  'type': instance.type,
+  'op': instance.op,
+  'channel_folder_id': instance.channelFolderId,
+  'data': instance.data,
+};
+
+ChannelFolderChange _$ChannelFolderChangeFromJson(Map<String, dynamic> json) =>
+    ChannelFolderChange(
+      name: json['name'] as String?,
+      description: json['description'] as String?,
+      renderedDescription: json['rendered_description'] as String?,
+      isArchived: json['is_archived'] as bool?,
+    );
+
+Map<String, dynamic> _$ChannelFolderChangeToJson(
+  ChannelFolderChange instance,
+) => <String, dynamic>{
+  'name': instance.name,
+  'description': instance.description,
+  'rendered_description': instance.renderedDescription,
+  'is_archived': instance.isArchived,
+};
+
+ChannelFolderReorderEvent _$ChannelFolderReorderEventFromJson(
+  Map<String, dynamic> json,
+) => ChannelFolderReorderEvent(
+  id: (json['id'] as num).toInt(),
+  order: (json['order'] as List<dynamic>)
+      .map((e) => (e as num).toInt())
+      .toList(),
+);
+
+Map<String, dynamic> _$ChannelFolderReorderEventToJson(
+  ChannelFolderReorderEvent instance,
+) => <String, dynamic>{
+  'id': instance.id,
+  'type': instance.type,
+  'op': instance.op,
+  'order': instance.order,
+};
+
 UserStatusEvent _$UserStatusEventFromJson(Map<String, dynamic> json) =>
     UserStatusEvent(
       id: (json['id'] as num).toInt(),
diff --git a/lib/api/model/initial_snapshot.dart b/lib/api/model/initial_snapshot.dart
index 8fa6ff0812..74be999eaf 100644
--- a/lib/api/model/initial_snapshot.dart
+++ b/lib/api/model/initial_snapshot.dart
@@ -52,6 +52,8 @@ class InitialSnapshot {
 
   final List<Subscription> subscriptions;
 
+  final List<ChannelFolder>? channelFolders; // TODO(server-11)
+
   final UnreadMessagesSnapshot unreadMsgs;
 
   final List<ZulipStream> streams;
@@ -168,6 +170,7 @@ class InitialSnapshot {
     required this.recentPrivateConversations,
     required this.savedSnippets,
     required this.subscriptions,
+    required this.channelFolders,
     required this.unreadMsgs,
     required this.streams,
     required this.userStatuses,
diff --git a/lib/api/model/initial_snapshot.g.dart b/lib/api/model/initial_snapshot.g.dart
index 2cf52446ca..dda2c9e1a0 100644
--- a/lib/api/model/initial_snapshot.g.dart
+++ b/lib/api/model/initial_snapshot.g.dart
@@ -63,6 +63,9 @@ InitialSnapshot _$InitialSnapshotFromJson(
   subscriptions: (json['subscriptions'] as List<dynamic>)
       .map((e) => Subscription.fromJson(e as Map<String, dynamic>))
       .toList(),
+  channelFolders: (json['channel_folders'] as List<dynamic>?)
+      ?.map((e) => ChannelFolder.fromJson(e as Map<String, dynamic>))
+      .toList(),
   unreadMsgs: UnreadMessagesSnapshot.fromJson(
     json['unread_msgs'] as Map<String, dynamic>,
   ),
@@ -166,6 +169,7 @@ Map<String, dynamic> _$InitialSnapshotToJson(
   'recent_private_conversations': instance.recentPrivateConversations,
   'saved_snippets': instance.savedSnippets,
   'subscriptions': instance.subscriptions,
+  'channel_folders': instance.channelFolders,
   'unread_msgs': instance.unreadMsgs,
   'streams': instance.streams,
   'user_status': instance.userStatuses.map((k, e) => MapEntry(k.toString(), e)),
diff --git a/lib/api/model/model.dart b/lib/api/model/model.dart
index fdfd0c856d..24ca2a8919 100644
--- a/lib/api/model/model.dart
+++ b/lib/api/model/model.dart
@@ -643,6 +643,8 @@ class ZulipStream {
   final int dateCreated;
   int? firstMessageId;
 
+  int? folderId;
+
   bool inviteOnly;
   bool isWebPublic; // present since 2.1, according to /api/changelog
   bool historyPublicToSubscribers;
@@ -673,6 +675,7 @@ class ZulipStream {
     required this.historyPublicToSubscribers,
     required this.messageRetentionDays,
     required this.channelPostPolicy,
+    required this.folderId,
     required this.canAddSubscribersGroup,
     required this.canDeleteAnyMessageGroup,
     required this.canDeleteOwnMessageGroup,
@@ -696,6 +699,7 @@ class ZulipStream {
       historyPublicToSubscribers: subscription.historyPublicToSubscribers,
       messageRetentionDays: subscription.messageRetentionDays,
       channelPostPolicy: subscription.channelPostPolicy,
+      folderId: subscription.folderId,
       canAddSubscribersGroup: subscription.canAddSubscribersGroup,
       canDeleteAnyMessageGroup: subscription.canDeleteAnyMessageGroup,
       canDeleteOwnMessageGroup: subscription.canDeleteOwnMessageGroup,
@@ -732,6 +736,7 @@ enum ChannelPropertyName {
   messageRetentionDays,
   @JsonValue('stream_post_policy')
   channelPostPolicy,
+  folderId,
   canAddSubscribersGroup,
   canDeleteAnyMessageGroup,
   canDeleteOwnMessageGroup,
@@ -816,6 +821,7 @@ class Subscription extends ZulipStream {
     required super.historyPublicToSubscribers,
     required super.messageRetentionDays,
     required super.channelPostPolicy,
+    required super.folderId,
     required super.canAddSubscribersGroup,
     required super.canDeleteAnyMessageGroup,
     required super.canDeleteOwnMessageGroup,
@@ -839,6 +845,38 @@ class Subscription extends ZulipStream {
   Map<String, dynamic> toJson() => _$SubscriptionToJson(this);
 }
 
+/// As in `channel_folders` in the initial snapshot.
+///
+/// For docs, search for "channel_folders:"
+/// in <https://zulip.com/api/register-queue>.
+@JsonSerializable(fieldRename: FieldRename.snake)
+class ChannelFolder {
+  final int id;
+  String name;
+  int? order; // TODO(server-11); added in a later FL than the rest
+  final int? dateCreated;
+  final int? creatorId;
+  String description;
+  String renderedDescription;
+  bool isArchived;
+
+  ChannelFolder({
+    required this.id,
+    required this.name,
+    required this.order,
+    required this.dateCreated,
+    required this.creatorId,
+    required this.description,
+    required this.renderedDescription,
+    required this.isArchived,
+  });
+
+  factory ChannelFolder.fromJson(Map<String, dynamic> json) =>
+    _$ChannelFolderFromJson(json);
+
+  Map<String, dynamic> toJson() => _$ChannelFolderToJson(this);
+}
+
 @JsonEnum(fieldRename: FieldRename.snake, valueField: "apiValue")
 enum UserTopicVisibilityPolicy {
   none(apiValue: 0),
diff --git a/lib/api/model/model.g.dart b/lib/api/model/model.g.dart
index 70316ae1eb..b835c493c5 100644
--- a/lib/api/model/model.g.dart
+++ b/lib/api/model/model.g.dart
@@ -251,6 +251,7 @@ ZulipStream _$ZulipStreamFromJson(Map<String, dynamic> json) => ZulipStream(
     _$ChannelPostPolicyEnumMap,
     json['stream_post_policy'],
   ),
+  folderId: (json['folder_id'] as num?)?.toInt(),
   canAddSubscribersGroup: json['can_add_subscribers_group'] == null
       ? null
       : GroupSettingValue.fromJson(json['can_add_subscribers_group']),
@@ -278,6 +279,7 @@ Map<String, dynamic> _$ZulipStreamToJson(ZulipStream instance) =>
       'rendered_description': instance.renderedDescription,
       'date_created': instance.dateCreated,
       'first_message_id': instance.firstMessageId,
+      'folder_id': instance.folderId,
       'invite_only': instance.inviteOnly,
       'is_web_public': instance.isWebPublic,
       'history_public_to_subscribers': instance.historyPublicToSubscribers,
@@ -315,6 +317,7 @@ Subscription _$SubscriptionFromJson(Map<String, dynamic> json) => Subscription(
     _$ChannelPostPolicyEnumMap,
     json['stream_post_policy'],
   ),
+  folderId: (json['folder_id'] as num?)?.toInt(),
   canAddSubscribersGroup: json['can_add_subscribers_group'] == null
       ? null
       : GroupSettingValue.fromJson(json['can_add_subscribers_group']),
@@ -350,6 +353,7 @@ Map<String, dynamic> _$SubscriptionToJson(Subscription instance) =>
       'rendered_description': instance.renderedDescription,
       'date_created': instance.dateCreated,
       'first_message_id': instance.firstMessageId,
+      'folder_id': instance.folderId,
       'invite_only': instance.inviteOnly,
       'is_web_public': instance.isWebPublic,
       'history_public_to_subscribers': instance.historyPublicToSubscribers,
@@ -371,6 +375,30 @@ Map<String, dynamic> _$SubscriptionToJson(Subscription instance) =>
       'color': instance.color,
     };
 
+ChannelFolder _$ChannelFolderFromJson(Map<String, dynamic> json) =>
+    ChannelFolder(
+      id: (json['id'] as num).toInt(),
+      name: json['name'] as String,
+      order: (json['order'] as num?)?.toInt(),
+      dateCreated: (json['date_created'] as num?)?.toInt(),
+      creatorId: (json['creator_id'] as num?)?.toInt(),
+      description: json['description'] as String,
+      renderedDescription: json['rendered_description'] as String,
+      isArchived: json['is_archived'] as bool,
+    );
+
+Map<String, dynamic> _$ChannelFolderToJson(ChannelFolder instance) =>
+    <String, dynamic>{
+      'id': instance.id,
+      'name': instance.name,
+      'order': instance.order,
+      'date_created': instance.dateCreated,
+      'creator_id': instance.creatorId,
+      'description': instance.description,
+      'rendered_description': instance.renderedDescription,
+      'is_archived': instance.isArchived,
+    };
+
 StreamConversation _$StreamConversationFromJson(Map<String, dynamic> json) {
   $checkKeys(
     json,
@@ -520,6 +548,7 @@ const _$ChannelPropertyNameEnumMap = {
   ChannelPropertyName.inviteOnly: 'invite_only',
   ChannelPropertyName.messageRetentionDays: 'message_retention_days',
   ChannelPropertyName.channelPostPolicy: 'stream_post_policy',
+  ChannelPropertyName.folderId: 'folder_id',
   ChannelPropertyName.canAddSubscribersGroup: 'can_add_subscribers_group',
   ChannelPropertyName.canDeleteAnyMessageGroup: 'can_delete_any_message_group',
   ChannelPropertyName.canDeleteOwnMessageGroup: 'can_delete_own_message_group',
diff --git a/lib/model/channel.dart b/lib/model/channel.dart
index ea05dc01d3..10e9596eed 100644
--- a/lib/model/channel.dart
+++ b/lib/model/channel.dart
@@ -42,6 +42,9 @@ mixin ChannelStore on UserStore {
   /// and [streamsByName].
   Map<int, Subscription> get subscriptions;
 
+  /// All the channel folders, including archived ones, indexed by ID.
+  Map<int, ChannelFolder> get channelFolders;
+
   static int compareChannelsByName(ZulipStream a, ZulipStream b) {
     // A user gave feedback wanting zulip-flutter to match web in putting
     // emoji-prefixed channels first; see #1202.
@@ -60,6 +63,21 @@ mixin ChannelStore on UserStore {
   // ignore: valid_regexps
   static final _startsWithEmojiRegex = RegExp(r'^\p{Emoji}', unicode: true);
 
+  /// A compare function for [ChannelFolder]s, using [ChannelFolder.order].
+  ///
+  /// Channels without [ChannelFolder.order] will come first,
+  /// sorted alphabetically.
+  // TODO(server-11) Once [ChannelFolder.order] is required,
+  //   remove alphabetical sorting.
+  static int compareChannelFolders(ChannelFolder a, ChannelFolder b) {
+    return switch ((a.order, b.order)) {
+      (null,   null) => a.name.toLowerCase().compareTo(b.name.toLowerCase()),
+      (null,  int()) => -1,
+      (int(),  null) => 1,
+      (int a, int b) => a.compareTo(b),
+    };
+  }
+
   /// The visibility policy that the self-user has for the given topic.
   ///
   /// This does not incorporate the user's channel-level policy,
@@ -267,6 +285,9 @@ mixin ProxyChannelStore on ChannelStore {
   @override
   Map<int, Subscription> get subscriptions => channelStore.subscriptions;
 
+  @override
+  Map<int, ChannelFolder> get channelFolders => channelStore.channelFolders;
+
   @override
   UserTopicVisibilityPolicy topicVisibilityPolicy(int streamId, TopicName topic) =>
     channelStore.topicVisibilityPolicy(streamId, topic);
@@ -306,6 +327,9 @@ class ChannelStoreImpl extends HasUserStore with ChannelStore {
       streams.putIfAbsent(stream.streamId, () => stream);
     }
 
+    final channelFolders = Map.fromEntries((initialSnapshot.channelFolders ?? [])
+      .map((channelFolder) => MapEntry(channelFolder.id, channelFolder)));
+
     final topicVisibility = <int, TopicKeyedMap<UserTopicVisibilityPolicy>>{};
     for (final item in initialSnapshot.userTopics) {
       if (_warnInvalidVisibilityPolicy(item.visibilityPolicy)) {
@@ -321,6 +345,7 @@ class ChannelStoreImpl extends HasUserStore with ChannelStore {
       streams: streams,
       streamsByName: streams.map((_, stream) => MapEntry(stream.name, stream)),
       subscriptions: subscriptions,
+      channelFolders: channelFolders,
       topicVisibility: topicVisibility,
     );
   }
@@ -330,6 +355,7 @@ class ChannelStoreImpl extends HasUserStore with ChannelStore {
     required this.streams,
     required this.streamsByName,
     required this.subscriptions,
+    required this.channelFolders,
     required this.topicVisibility,
   });
 
@@ -339,6 +365,8 @@ class ChannelStoreImpl extends HasUserStore with ChannelStore {
   final Map<String, ZulipStream> streamsByName;
   @override
   final Map<int, Subscription> subscriptions;
+  @override
+  final Map<int, ChannelFolder> channelFolders;
 
   @override
   Map<int, TopicKeyedMap<UserTopicVisibilityPolicy>> get debugTopicVisibility => topicVisibility;
@@ -418,6 +446,8 @@ class ChannelStoreImpl extends HasUserStore with ChannelStore {
             stream.messageRetentionDays = event.value as int?;
           case ChannelPropertyName.channelPostPolicy:
             stream.channelPostPolicy = event.value as ChannelPostPolicy;
+          case ChannelPropertyName.folderId:
+            stream.folderId = event.value as int?;
           case ChannelPropertyName.canAddSubscribersGroup:
             stream.canAddSubscribersGroup = event.value as GroupSettingValue;
           case ChannelPropertyName.canDeleteAnyMessageGroup:
@@ -496,6 +526,33 @@ class ChannelStoreImpl extends HasUserStore with ChannelStore {
     }
   }
 
+  void handleChannelFolderEvent(ChannelFolderEvent event) {
+    switch (event) {
+      case ChannelFolderAddEvent():
+        final newChannelFolder = event.channelFolder;
+        channelFolders[newChannelFolder.id] = newChannelFolder;
+
+      case ChannelFolderUpdateEvent():
+        final change = event.data;
+        final channelFolder = channelFolders[event.channelFolderId];
+        if (channelFolder == null) return; // TODO(log)
+
+        if (change.name != null)                channelFolder.name = change.name!;
+        if (change.description != null)         channelFolder.description = change.description!;
+        if (change.renderedDescription != null) channelFolder.renderedDescription = change.renderedDescription!;
+        if (change.isArchived != null)          channelFolder.isArchived = change.isArchived!;
+
+      case ChannelFolderReorderEvent():
+        final order = event.order;
+        for (int i = 0; i < order.length; i++) {
+          final id = order[i];
+          final channelFolder = channelFolders[id];
+          if (channelFolder == null) continue; // TODO(log)
+          channelFolder.order = i;
+        }
+    }
+  }
+
   void handleUserTopicEvent(UserTopicEvent event) {
     UserTopicVisibilityPolicy visibilityPolicy = event.visibilityPolicy;
     if (_warnInvalidVisibilityPolicy(visibilityPolicy)) {
diff --git a/lib/model/store.dart b/lib/model/store.dart
index 8fbff2e16a..88ca778100 100644
--- a/lib/model/store.dart
+++ b/lib/model/store.dart
@@ -829,6 +829,11 @@ class PerAccountStore extends PerAccountStoreBase with
         _channels.handleSubscriptionEvent(event);
         notifyListeners();
 
+      case ChannelFolderEvent():
+        assert(debugLog("server event: channel_folder/${event.op}"));
+        _channels.handleChannelFolderEvent(event);
+        break;
+
       case UserStatusEvent():
         assert(debugLog("server event: user_status"));
         _users.handleUserStatusEvent(event);
diff --git a/test/api/model/model_checks.dart b/test/api/model/model_checks.dart
index 96a223c084..a7db054b55 100644
--- a/test/api/model/model_checks.dart
+++ b/test/api/model/model_checks.dart
@@ -56,6 +56,17 @@ extension ZulipStreamChecks on Subject<ZulipStream> {
   Subject<int> get streamId => has((x) => x.streamId, 'streamId');
 }
 
+extension ChannelFolderChecks on Subject<ChannelFolder> {
+  Subject<int> get id => has((x) => x.id, 'id');
+  Subject<String> get name => has((x) => x.name, 'name');
+  Subject<int?> get order => has((x) => x.order, 'order');
+  Subject<int?> get dateCreated => has((x) => x.dateCreated, 'dateCreated');
+  Subject<int?> get creatorId => has((x) => x.creatorId, 'creatorId');
+  Subject<String> get description => has((x) => x.description, 'description');
+  Subject<String> get renderedDescription => has((x) => x.renderedDescription, 'renderedDescription');
+  Subject<bool> get isArchived => has((x) => x.isArchived, 'isArchived');
+}
+
 extension TopicNameChecks on Subject<TopicName> {
   Subject<String> get apiName => has((x) => x.apiName, 'apiName');
   Subject<String?> get displayName => has((x) => x.displayName, 'displayName');
diff --git a/test/example_data.dart b/test/example_data.dart
index cf15221716..e894882225 100644
--- a/test/example_data.dart
+++ b/test/example_data.dart
@@ -465,6 +465,7 @@ ZulipStream stream({
   bool? historyPublicToSubscribers,
   int? messageRetentionDays,
   ChannelPostPolicy? channelPostPolicy,
+  int? folderId,
   GroupSettingValue? canAddSubscribersGroup,
   GroupSettingValue? canDeleteAnyMessageGroup,
   GroupSettingValue? canDeleteOwnMessageGroup,
@@ -496,6 +497,7 @@ ZulipStream stream({
     historyPublicToSubscribers: historyPublicToSubscribers ?? true,
     messageRetentionDays: messageRetentionDays,
     channelPostPolicy: channelPostPolicy ?? ChannelPostPolicy.any,
+    folderId: folderId,
     canAddSubscribersGroup: canAddSubscribersGroup ?? GroupSettingValueNamed(nobodyGroup.id),
     canDeleteAnyMessageGroup: canDeleteAnyMessageGroup ?? GroupSettingValueNamed(nobodyGroup.id),
     canDeleteOwnMessageGroup: canDeleteOwnMessageGroup ?? GroupSettingValueNamed(nobodyGroup.id),
@@ -540,6 +542,7 @@ Subscription subscription(
     historyPublicToSubscribers: stream.historyPublicToSubscribers,
     messageRetentionDays: stream.messageRetentionDays,
     channelPostPolicy: stream.channelPostPolicy,
+    folderId: stream.folderId,
     canAddSubscribersGroup: stream.canAddSubscribersGroup,
     canDeleteAnyMessageGroup: stream.canDeleteAnyMessageGroup,
     canDeleteOwnMessageGroup: stream.canDeleteOwnMessageGroup,
@@ -557,6 +560,49 @@ Subscription subscription(
   );
 }
 
+/// A fresh channel folder ID,
+/// from a random but always strictly increasing sequence.
+int _nextChannelFolderId() => (_lastChannelFolderId += 1 + Random().nextInt(100));
+int _lastChannelFolderId = 1000;
+
+ChannelFolder channelFolder({
+  int? id,
+  String? name,
+  int? order,
+  int? dateCreated,
+  int? creatorId,
+  String? description,
+  String? renderedDescription,
+  bool? isArchived,
+}) {
+  final effectiveId = id ?? _nextChannelFolderId();
+  final effectiveDescription = description ?? 'An example channel folder.';
+  return ChannelFolder(
+    id: effectiveId,
+    name: name ?? 'channel folder $effectiveId',
+    order: order,
+    dateCreated: dateCreated ?? utcTimestamp(),
+    creatorId: creatorId ?? selfUser.userId,
+    description: effectiveDescription,
+    renderedDescription: renderedDescription ?? '<p>$effectiveDescription</p>',
+    isArchived: isArchived ?? false,
+  );
+}
+
+ChannelFolderChange channelFolderChange({
+  String? name,
+  String? description,
+  String? renderedDescription,
+  bool? isArchived,
+}) {
+  return ChannelFolderChange(
+    name: name,
+    description: description,
+    renderedDescription: renderedDescription,
+    isArchived: isArchived,
+  );
+}
+
 /// The [TopicName] constructor, but shorter.
 ///
 /// Useful in test code that mentions a lot of topics in a compact format.
@@ -1217,6 +1263,8 @@ ChannelUpdateEvent channelUpdateEvent(
       assert(value is int?);
     case ChannelPropertyName.channelPostPolicy:
       assert(value is ChannelPostPolicy);
+    case ChannelPropertyName.folderId:
+      assert(value is int?);
     case ChannelPropertyName.canAddSubscribersGroup:
     case ChannelPropertyName.canDeleteAnyMessageGroup:
     case ChannelPropertyName.canDeleteOwnMessageGroup:
@@ -1276,6 +1324,7 @@ InitialSnapshot initialSnapshot({
   List<RecentDmConversation>? recentPrivateConversations,
   List<SavedSnippet>? savedSnippets,
   List<Subscription>? subscriptions,
+  List<ChannelFolder>? channelFolders,
   UnreadMessagesSnapshot? unreadMsgs,
   List<ZulipStream>? streams,
   Map<int, UserStatusChange>? userStatuses,
@@ -1332,6 +1381,7 @@ InitialSnapshot initialSnapshot({
     recentPrivateConversations: recentPrivateConversations ?? [],
     savedSnippets: savedSnippets ?? [],
     subscriptions: subscriptions ?? [], // TODO add subscriptions to default
+    channelFolders: channelFolders ?? [],
     unreadMsgs: unreadMsgs ?? _unreadMsgs(),
     streams: streams ?? [], // TODO add streams to default
     userStatuses: userStatuses ?? {},
diff --git a/test/model/channel_test.dart b/test/model/channel_test.dart
index e73965dac2..6c2de3e83c 100644
--- a/test/model/channel_test.dart
+++ b/test/model/channel_test.dart
@@ -1,4 +1,5 @@
 import 'package:checks/checks.dart';
+import 'package:collection/collection.dart';
 import 'package:test/scaffolding.dart';
 import 'package:zulip/api/model/events.dart';
 import 'package:zulip/api/model/initial_snapshot.dart';
@@ -91,6 +92,21 @@ void main() {
     });
   });
 
+  group('channelFolderComparator', () {
+    final folder1 = eg.channelFolder(id: 1, order: null, name: 'M');
+    final folder2 = eg.channelFolder(id: 2, order: null, name: 'n');
+    final folder3 = eg.channelFolder(id: 3, order: 2, name: 'a');
+    final folder4 = eg.channelFolder(id: 4, order: 0, name: 'b');
+    final folder5 = eg.channelFolder(id: 5, order: 1, name: 'c');
+
+    final store = eg.store(initialSnapshot: eg.initialSnapshot(
+      channelFolders: [folder1, folder2, folder3, folder4, folder5]));
+
+    final sorted = store.channelFolders.values.toList()
+      .sorted(ChannelStore.compareChannelFolders);
+    check(sorted).deepEquals([folder1, folder2, folder4, folder5, folder3]);
+  });
+
   group('SubscriptionEvent', () {
     final stream = eg.stream();
 
@@ -123,6 +139,88 @@ void main() {
     });
   });
 
+  group('ChannelFolderEvent', () {
+    group('add', () {
+      test('smoke', () async {
+        final folder1 = eg.channelFolder(id: 1);
+        final folder2 = eg.channelFolder(id: 2);
+        final store = eg.store(initialSnapshot: eg.initialSnapshot(
+          channelFolders: [folder1]));
+
+        await store.handleEvent(ChannelFolderAddEvent(
+          id: 1, channelFolder: folder2));
+        check(store.channelFolders).deepEquals({1: folder1, 2: folder2});
+      });
+    });
+
+    group('update', () {
+      void doTest(ChannelFolderChange change) {
+        final ChannelFolderChange(
+          :name, :description, :renderedDescription, :isArchived) = change;
+        final testDescription = [
+          if (name != null)                'name: $name',
+          if (description != null)         'description: $description',
+          if (renderedDescription != null) 'renderedDescription: $renderedDescription',
+          if (isArchived != null)          'isArchived: $isArchived',
+        ].join(', ');
+        test(testDescription, () async {
+          final channelFolder = eg.channelFolder();
+          assert(name == null || name != channelFolder.name);
+          assert(description == null || description != channelFolder.description);
+          assert(renderedDescription == null || renderedDescription != channelFolder.renderedDescription);
+          assert(isArchived == null || isArchived != channelFolder.isArchived);
+
+          final store = eg.store(initialSnapshot: eg.initialSnapshot(
+            channelFolders: [channelFolder]));
+          await store.handleEvent(ChannelFolderUpdateEvent(id: 1,
+            channelFolderId: channelFolder.id, data: change));
+          check(store.channelFolders.values.single)
+            ..name.equals(name ?? channelFolder.name)
+            ..description.equals(description ?? channelFolder.description)
+            ..renderedDescription.equals(renderedDescription ?? channelFolder.renderedDescription)
+            ..isArchived.equals(isArchived ?? channelFolder.isArchived);
+        });
+      }
+
+      doTest(eg.channelFolderChange(name: 'new name'));
+      doTest(eg.channelFolderChange(description: 'new description'));
+      doTest(eg.channelFolderChange(renderedDescription: '<p>new description</p>'));
+      doTest(eg.channelFolderChange(isArchived: true));
+
+      doTest(eg.channelFolderChange(
+        name: 'new name',
+        description: 'new description',
+        renderedDescription: '<p>new description</p>',
+        isArchived: true,
+      ));
+    });
+
+    group('reorder', () {
+      List<ChannelFolder> foldersFromStoreInOrder(PerAccountStore store) {
+        return store.channelFolders.values.toList()
+          ..sort((a, b) => a.order!.compareTo(b.order!));
+      }
+
+      test('smoke', () async {
+        final folderA = eg.channelFolder(order: 0);
+        final folderB = eg.channelFolder(order: 1);
+        final folderC = eg.channelFolder(order: 2);
+
+        final store = eg.store(initialSnapshot: eg.initialSnapshot(
+          channelFolders: [folderA, folderB, folderC]));
+        check(foldersFromStoreInOrder(store)).deepEquals([folderA, folderB, folderC]);
+
+        await store.handleEvent(ChannelFolderReorderEvent(id: 1,
+          order: [folderA.id, folderC.id, folderB.id]));
+        check(foldersFromStoreInOrder(store)).deepEquals([folderA, folderC, folderB]);
+
+        await store.handleEvent(ChannelFolderReorderEvent(id: 1,
+          order: [folderC.id, folderB.id, folderA.id]));
+        check(foldersFromStoreInOrder(store)).deepEquals([folderC, folderB, folderA]);
+      });
+    });
+  });
+
   group('topic visibility', () {
     final stream1 = eg.stream();
     final stream2 = eg.stream();
diff --git a/test/model/test_store.dart b/test/model/test_store.dart
index 303f59974b..5bf78f3f4a 100644
--- a/test/model/test_store.dart
+++ b/test/model/test_store.dart
@@ -350,6 +350,10 @@ extension PerAccountStoreTestExtension on PerAccountStore {
     await handleEvent(SubscriptionRemoveEvent(id: 1, streamIds: channelIds));
   }
 
+  Future<void> addChannelFolder(ChannelFolder channelFolder) async {
+    await handleEvent(ChannelFolderAddEvent(id: 1, channelFolder: channelFolder));
+  }
+
   Future<void> setUserTopic(ZulipStream stream, String topic, UserTopicVisibilityPolicy visibilityPolicy) async {
     await handleEvent(eg.userTopicEvent(stream.streamId, topic, visibilityPolicy));
   }