diff --git a/apps/gridcraft/src/native_menu.rs b/apps/gridcraft/src/native_menu.rs
index 6985af3c0..7dc549cb7 100644
--- a/apps/gridcraft/src/native_menu.rs
+++ b/apps/gridcraft/src/native_menu.rs
@@ -125,7 +125,7 @@ fn tree() -> Vec<(&'static str, Vec<Entry>)> {
                 ("Unhide Sheet…", "sheet.unhide", None),
                 ("-", "", None),
                 ("Conditional Formatting…", "dialog:manageRules", None),
-                ("Format as Table", "insert.table", None),
+                ("Format as Table", "home.formatAsTable", None),
             ],
         ),
         (
diff --git a/crates/engine/src/cmd/insert.rs b/crates/engine/src/cmd/insert.rs
index aae5a9faa..2388d1f25 100644
--- a/crates/engine/src/cmd/insert.rs
+++ b/crates/engine/src/cmd/insert.rs
@@ -26,9 +26,9 @@ pub fn specs() -> Vec<CommandSpec> {
             "Format as Table",
             ["Home", "Styles"],
             None,
-            "{range?, style: \"TableStyleMedium2\", header?}",
+            "{range?, style: \"TableStyleMedium2\", header?} (inside a table: restyles it)",
             has_doc,
-            insert_table
+            format_as_table
         ),
         cmd!("table.totalRow", "Total Row", ["Table", "Table Style Options"], None, "{table?, on?: bool}", has_doc, |s, p| table_flag(
             s, p, "totals"
@@ -351,6 +351,21 @@ fn insert_table(s: &mut Session, p: &Json) -> Result<Json> {
     })
 }
 
+/// Format as Table inside a table restyles that table, as in Excel; elsewhere it makes a new one.
+fn format_as_table(s: &mut Session, p: &Json) -> Result<Json> {
+    // Without a range, the active area decides (as in insert_table), not the first one.
+    let r = if p.get("range").is_some() { target_range(s, p)? } else { s.doc()?.selection.current() };
+    let sheet = target_sheet(s, p)?;
+    let inside = s.doc()?.wb.sheet(sheet).and_then(|sh| sh.tables.iter().find(|t| t.range.contains_range(&r))).map(|t| (t.name.clone(), t.range));
+    match inside {
+        Some((table, range)) => {
+            table_style(s, &with(p, "table", json!(table)))?;
+            Ok(json!({"table": table, "range": range.a1()}))
+        }
+        None => insert_table(s, p),
+    }
+}
+
 fn find_table(s: &Session, p: &Json) -> Result<(usize, usize)> {
     let d = s.doc()?;
     if let Some(n) = str_param(p, "table") {
diff --git a/crates/engine/tests/format_as_table_restyle.rs b/crates/engine/tests/format_as_table_restyle.rs
new file mode 100644
index 000000000..0419027c6
--- /dev/null
+++ b/crates/engine/tests/format_as_table_restyle.rs
@@ -0,0 +1,61 @@
+use gridcraft_engine::Session;
+use serde_json::json;
+
+fn table() -> Session {
+    let mut s = Session::new();
+    s.new_workbook();
+    s.execute("range.setValues", json!({"range":"A1", "values":[["Item", "Qty"], ["x", "7"], ["y", "8"]]})).unwrap();
+    s.execute("insert.table", json!({"range":"A1:B3", "header":true, "name":"T"})).unwrap();
+    s
+}
+
+fn styles(s: &Session) -> Vec<String> {
+    s.doc().unwrap().wb.active().unwrap().tables.iter().map(|t| t.style.clone()).collect()
+}
+
+#[test]
+fn format_as_table_inside_a_table_restyles_it() {
+    let mut s = table();
+    s.execute("selection.set", json!({"range":"B2"})).unwrap();
+    s.execute("home.formatAsTable", json!({"style":"TableStyleLight9"})).unwrap();
+    assert_eq!(styles(&s), ["TableStyleLight9"]);
+}
+
+#[test]
+fn format_as_table_on_a_range_inside_a_table_restyles_it() {
+    let mut s = table();
+    s.execute("home.formatAsTable", json!({"range":"A2:B3", "style":"TableStyleDark3"})).unwrap();
+    assert_eq!(styles(&s), ["TableStyleDark3"]);
+}
+
+#[test]
+fn format_as_table_across_a_table_edge_is_rejected() {
+    let mut s = table();
+    let e = s.execute("home.formatAsTable", json!({"range":"A1:C3", "style":"TableStyleLight9"})).unwrap_err();
+    assert!(e.to_string().contains("overlap"), "{e}");
+    assert_eq!(styles(&s), ["TableStyleMedium2"]);
+}
+
+#[test]
+fn format_as_table_inside_a_table_returns_that_table() {
+    let mut s = table();
+    let r = s.execute("home.formatAsTable", json!({"range":"B2", "style":"TableStyleLight9"})).unwrap();
+    assert_eq!(r, json!({"table":"T", "range":"A1:B3"}));
+}
+
+#[test]
+fn format_as_table_uses_the_active_area_of_a_multi_area_selection() {
+    let mut s = table();
+    s.execute("selection.set", json!({"range":"D10:E11,B2"})).unwrap();
+    s.execute("home.formatAsTable", json!({"style":"TableStyleLight9"})).unwrap();
+    assert_eq!(styles(&s), ["TableStyleLight9"]);
+}
+
+#[test]
+fn format_as_table_inside_a_table_with_data_beside_it_restyles_it() {
+    let mut s = table();
+    s.execute("range.setValues", json!({"range":"C1", "values":[["Note"], ["a"], ["b"]]})).unwrap();
+    s.execute("selection.set", json!({"range":"B2"})).unwrap();
+    s.execute("home.formatAsTable", json!({"style":"TableStyleLight9"})).unwrap();
+    assert_eq!(styles(&s), ["TableStyleLight9"]);
+}