diff --git a/app/dirlist.go b/app/dirlist.go
index 23842e3f..9969a996 100644
--- a/app/dirlist.go
+++ b/app/dirlist.go
@@ -36,8 +36,8 @@ type DirectoryLister interface {
 
 	NextPrev(int)
 
-	CollapseFolder()
-	ExpandFolder()
+	CollapseFolder(string)
+	ExpandFolder(string)
 
 	SelectedMsgStore() (*lib.MessageStore, bool)
 	MsgStore(string) (*lib.MessageStore, bool)
@@ -170,11 +170,11 @@ func (dirlist *DirectoryList) Update(msg types.WorkerMessage) {
 	}
 }
 
-func (dirlist *DirectoryList) CollapseFolder() {
+func (dirlist *DirectoryList) CollapseFolder(string) {
 	// no effect for the DirectoryList
 }
 
-func (dirlist *DirectoryList) ExpandFolder() {
+func (dirlist *DirectoryList) ExpandFolder(string) {
 	// no effect for the DirectoryList
 }
 
diff --git a/app/dirtree.go b/app/dirtree.go
index 22f0c8a9..30ced9a6 100644
--- a/app/dirtree.go
+++ b/app/dirtree.go
@@ -304,30 +304,35 @@ func (dt *DirectoryTree) selectIndex(i int) {
 	}
 }
 
-func (dt *DirectoryTree) CollapseFolder() {
-	if dt.listIdx >= 0 && dt.listIdx < len(dt.list) {
-		if node := dt.list[dt.listIdx]; node != nil {
-			if node.Parent != nil && (node.Hidden != 0 || node.FirstChild == nil) {
-				node.Parent.Hidden = 1
-				// highlight parent node and select it
-				for i, t := range dt.list {
-					if t == node.Parent {
-						dt.selectIndex(i)
-					}
-				}
-			} else {
-				node.Hidden = 1
+func (dt *DirectoryTree) CollapseFolder(name string) {
+	name = strings.TrimRight(name, dt.worker.PathSeparator())
+	index, node := dt.getTreeNode(models.UID(name))
+	if node == nil {
+		return
+	}
+	if node.Parent != nil && (node.Hidden != 0 || node.FirstChild == nil) {
+		node.Parent.Hidden = 1
+		// highlight parent node and select it
+		for i, t := range dt.list {
+			if t == node.Parent && index == dt.listIdx {
+				dt.selectIndex(i)
+				break
 			}
-			dt.Invalidate()
 		}
+	} else {
+		node.Hidden = 1
 	}
+	dt.Invalidate()
 }
 
-func (dt *DirectoryTree) ExpandFolder() {
-	if dt.listIdx >= 0 && dt.listIdx < len(dt.list) {
-		dt.list[dt.listIdx].Hidden = 0
-		dt.Invalidate()
+func (dt *DirectoryTree) ExpandFolder(name string) {
+	name = strings.TrimRight(name, dt.worker.PathSeparator())
+	_, node := dt.getTreeNode(models.UID(name))
+	if node == nil {
+		return
 	}
+	node.Hidden = 0
+	dt.Invalidate()
 }
 
 func (dt *DirectoryTree) countVisible(list []*types.Thread) (n int) {
diff --git a/commands/account/expand-folder.go b/commands/account/expand-folder.go
index 8b1a8c66..0422c55e 100644
--- a/commands/account/expand-folder.go
+++ b/commands/account/expand-folder.go
@@ -7,7 +7,9 @@ import (
 	"git.sr.ht/~rjarry/aerc/commands"
 )
 
-type ExpandCollapseFolder struct{}
+type ExpandCollapseFolder struct {
+	Folder string `opt:"folder" required:"false" complete:"CompleteFolder" desc:"Folder name."`
+}
 
 func init() {
 	commands.Register(ExpandCollapseFolder{})
@@ -25,15 +27,26 @@ func (ExpandCollapseFolder) Aliases() []string {
 	return []string{"expand-folder", "collapse-folder"}
 }
 
-func (ExpandCollapseFolder) Execute(args []string) error {
+func (*ExpandCollapseFolder) CompleteFolder(arg string) []string {
+	acct := app.SelectedAccount()
+	if acct == nil {
+		return nil
+	}
+	return commands.FilterList(acct.Directories().List(), arg, nil)
+}
+
+func (e ExpandCollapseFolder) Execute(args []string) error {
 	acct := app.SelectedAccount()
 	if acct == nil {
 		return errors.New("No account selected")
 	}
+	if e.Folder == "" {
+		e.Folder = acct.Directories().Selected()
+	}
 	if args[0] == "expand-folder" {
-		acct.Directories().ExpandFolder()
+		acct.Directories().ExpandFolder(e.Folder)
 	} else {
-		acct.Directories().CollapseFolder()
+		acct.Directories().CollapseFolder(e.Folder)
 	}
 	return nil
 }
diff --git a/doc/aerc.1.scd b/doc/aerc.1.scd
index 6de06175..1647a67e 100644
--- a/doc/aerc.1.scd
+++ b/doc/aerc.1.scd
@@ -646,10 +646,11 @@ message list, the message in the message viewer, etc).
 	Cycles to the next (or previous) folder shown in the sidebar, repeated
 	_<n>_ times (default: _1_).
 
-*:expand-folder*++
-*:collapse-folder*
-	Expands or collapses the current folder when the directory tree is
-	enabled.
+*:expand-folder* [_<folder>_]++
+*:collapse-folder* [_<folder>_]
+	Expands or collapses a folder when the directory tree is enabled. If no
+	_<folder>_ argument is specified, the currently selected folder is acted
+	upon.
 
 *:export-mbox* _<file>_
 	Exports messages in the current folder to an mbox file. If there are marked