diff --git a/crates/calc/src/eval.rs b/crates/calc/src/eval.rs
index 063043a..fcc38c3 100644
--- a/crates/calc/src/eval.rs
+++ b/crates/calc/src/eval.rs
@@ -1320,7 +1320,8 @@ impl<'h> Evaluator<'h> {
         // SUBTOTAL documentation); 101-111 also leave out rows hidden by hand.
         let skip_filtered = name == "SUBTOTAL";
         let skip_errors = matches!(options, 2 | 3 | 6 | 7);
-        let skip_nested = options <= 3;
+        // SUBTOTAL always leaves out nested SUBTOTAL/AGGREGATE cells (101-111 too); AGGREGATE does so for options 0-3.
+        let skip_nested = name == "SUBTOTAL" || options <= 3;
         let mut values = Vec::new();
         let mut k = None;
         let refs = if name == "AGGREGATE" && func >= 14 { &rest[..1.min(rest.len())] } else { rest };
diff --git a/crates/calc/src/tests.rs b/crates/calc/src/tests.rs
index e2f4a3a..bfe697e 100644
--- a/crates/calc/src/tests.rs
+++ b/crates/calc/src/tests.rs
@@ -594,6 +594,29 @@ fn subtotal_skips_hidden() {
     assert_eq!(t.num("B2"), 6.0);
 }
 
+#[test]
+fn subtotal_109_skips_nested_subtotal() {
+    let mut t = T::new();
+    t.set("A1", "2");
+    t.set("A2", "=SUBTOTAL(9,A1)");
+    t.set("C1", "=SUBTOTAL(109,A1:A2)");
+    t.set("C2", "=SUBTOTAL(9,A1:A2)");
+    t.set("C3", "=SUBTOTAL(109,A1)");
+    assert_eq!(t.num("C1"), 2.0);
+    assert_eq!(t.num("C2"), 2.0);
+    assert_eq!(t.num("C3"), 2.0);
+    // Manually hidden rows are still left out by 109 only.
+    let mut t = T::new();
+    t.set("A1", "1");
+    t.set("A2", "2");
+    t.set("A3", "=SUBTOTAL(9,A1:A2)");
+    t.wb.sheet_mut(0).unwrap().rows.insert(1, gridcraft_model::LineInfo { hidden: true, ..Default::default() });
+    t.set("B1", "=SUBTOTAL(109,A1:A3)");
+    t.set("B2", "=SUBTOTAL(9,A1:A3)");
+    assert_eq!(t.num("B1"), 1.0);
+    assert_eq!(t.num("B2"), 3.0);
+}
+
 /// SUBTOTAL leaves out rows a filter hides for every function number, while 1-11 keep rows
 /// hidden by hand (as in ConditionalFormattingSamples.xlsx, where `SUBTOTAL(9,Table69[Sales])`
 /// under a filtered table adds only the visible rows).