From 60b2ddf825a4c32302003c47bedbabebc332f4b4 Mon Sep 17 00:00:00 2001
From: Isaac Hunja <isaac@kaara.works>
Date: Wed, 4 Mar 2026 06:53:47 +0300
Subject: [PATCH 1/2] fix(table-core): skip state update in toggleExpanded when
 state is unchanged

When calling row.toggleExpanded(bool) with a value matching the
current expanded state, the function would still trigger
onExpandedChange and cause unnecessary re-renders.

This adds an early return that checks the current expanded state
before proceeding with the state update, avoiding the overhead of
calling onExpandedChange when no state change is needed.

Closes #6136
---
 .../table-core/src/features/RowExpanding.ts   | 23 ++++++++++---------
 1 file changed, 12 insertions(+), 11 deletions(-)

diff --git a/packages/table-core/src/features/RowExpanding.ts b/packages/table-core/src/features/RowExpanding.ts
index 456108d4d4..fb190768d0 100644
--- a/packages/table-core/src/features/RowExpanding.ts
+++ b/packages/table-core/src/features/RowExpanding.ts
@@ -290,9 +290,16 @@ export const RowExpanding: TableFeature = {
     table: Table<TData>,
   ): void => {
     row.toggleExpanded = (expanded) => {
-      table.setExpanded((old) => {
-        const exists = old === true ? true : !!old?.[row.id]
+      const isCurrentlyExpanded = row.getIsExpanded()
+      const newExpanded = expanded ?? !isCurrentlyExpanded
+
+      // If the desired state matches the current state, skip the update
+      // to avoid unnecessary re-renders
+      if (newExpanded === isCurrentlyExpanded) {
+        return
+      }
 
+      table.setExpanded((old) => {
         let oldExpanded: ExpandedStateList = {}
 
         if (old === true) {
@@ -303,21 +310,15 @@ export const RowExpanding: TableFeature = {
           oldExpanded = old
         }
 
-        expanded = expanded ?? !exists
-
-        if (!exists && expanded) {
+        if (newExpanded) {
           return {
             ...oldExpanded,
             [row.id]: true,
           }
         }
 
-        if (exists && !expanded) {
-          const { [row.id]: _, ...rest } = oldExpanded
-          return rest
-        }
-
-        return old
+        const { [row.id]: _, ...rest } = oldExpanded
+        return rest
       })
     }
     row.getIsExpanded = () => {

From 6cd1aa963348dcc181239b90ba8f370a11954552 Mon Sep 17 00:00:00 2001
From: Isaac Hunja <isaac@kaara.works>
Date: Wed, 4 Mar 2026 07:10:17 +0300
Subject: [PATCH 2/2] chore: add changeset

---
 .changeset/fix-toggle-expanded-noop.md | 5 +++++
 1 file changed, 5 insertions(+)
 create mode 100644 .changeset/fix-toggle-expanded-noop.md

diff --git a/.changeset/fix-toggle-expanded-noop.md b/.changeset/fix-toggle-expanded-noop.md
new file mode 100644
index 0000000000..360084523d
--- /dev/null
+++ b/.changeset/fix-toggle-expanded-noop.md
@@ -0,0 +1,5 @@
+---
+'@tanstack/table-core': patch
+---
+
+Skip state update in toggleExpanded when the desired state matches the current state, avoiding unnecessary re-renders