diff --git a/crates/functions/src/math.rs b/crates/functions/src/math.rs
index 6d4cdcf58..f6a3b2efa 100644
--- a/crates/functions/src/math.rs
+++ b/crates/functions/src/math.rs
@@ -694,6 +694,16 @@ pub(crate) fn specs() -> Vec<FnSpec> {
         f!("ROUNDDOWN", 2, 2, MathTrig, S, "ROUNDDOWN(number, num_digits)", "Rounds a number toward zero to a given number of digits.", rounddown),
         f!("MROUND", 2, 2, MathTrig, S, "MROUND(number, multiple)", "Rounds a number to the nearest multiple.", mround),
         f!("CEILING", 2, 2, Compatibility, S, "CEILING(number, significance)", "Rounds a number up to a multiple of significance.", ceiling),
+        f!(
+            "ECMA.CEILING",
+            2,
+            2,
+            Compatibility,
+            S,
+            "ECMA.CEILING(number, significance)",
+            "Rounds a number up to a multiple of significance.",
+            ceiling
+        ),
         f!(
             "CEILING.MATH",
             1,
diff --git a/crates/functions/src/math/tests.rs b/crates/functions/src/math/tests.rs
index 14f72d1e1..503d4771c 100644
--- a/crates/functions/src/math/tests.rs
+++ b/crates/functions/src/math/tests.rs
@@ -101,6 +101,11 @@ fn rounding() {
     close(ev2("CEILING", 1.5, 0.1), 1.5);
     close(ev2("CEILING", 0.234, 0.01), 0.24);
     is_err(ev2("CEILING", 2.5, -1.0), Num);
+    // ECMA.CEILING is CEILING under a second name (Excel table from #2776).
+    close(ev2("ECMA.CEILING", 1.5, 1.0), 2.0);
+    close(ev2("ECMA.CEILING", -2.5, -2.0), -4.0);
+    close(ev2("ECMA.CEILING", 2.5, 0.0), 0.0);
+    is_err(ev2("ECMA.CEILING", 1.5, -1.0), Num);
     close(ev2("FLOOR", 3.7, 2.0), 2.0);
     close(ev2("FLOOR", -2.5, -2.0), -2.0);
     close(ev2("FLOOR", -2.5, 2.0), -4.0);