diff --git a/crates/nu-parser/src/parser.rs b/crates/nu-parser/src/parser.rs
index 3416e538df..0f72132d10 100644
--- a/crates/nu-parser/src/parser.rs
+++ b/crates/nu-parser/src/parser.rs
@@ -486,7 +486,7 @@ fn parse_short_flags(
                 && matches!(
                     sig.get_positional(positional_idx),
                     Some(PositionalArg {
-                        shape: SyntaxShape::Int | SyntaxShape::Number,
+                        shape: SyntaxShape::Int | SyntaxShape::Number | SyntaxShape::Float,
                         ..
                     })
                 )
diff --git a/tests/repl/test_custom_commands.rs b/tests/repl/test_custom_commands.rs
index 43a24fa250..1f36b0e90c 100644
--- a/tests/repl/test_custom_commands.rs
+++ b/tests/repl/test_custom_commands.rs
@@ -274,3 +274,9 @@ fn dont_allow_implicit_casting_between_glob_and_string() -> TestResult {
         "can't convert",
     )
 }
+
+#[test]
+fn allow_pass_negative_float() -> TestResult {
+    run_test("def spam [val: float] { $val }; spam -1.4", "-1.4")?;
+    run_test("def spam [val: float] { $val }; spam -2", "-2")
+}