diff --git a/Plugins/BridgeJS/Sources/BridgeJSLink/BridgeJSLink.swift b/Plugins/BridgeJS/Sources/BridgeJSLink/BridgeJSLink.swift
index ce9d4bb67..499d6f60b 100644
--- a/Plugins/BridgeJS/Sources/BridgeJSLink/BridgeJSLink.swift
+++ b/Plugins/BridgeJS/Sources/BridgeJSLink/BridgeJSLink.swift
@@ -1834,7 +1834,7 @@ extension BridgeJSLink {
         let returnExpr = try thunkBuilder.call(abiName: function.abiName, returnType: function.returnType)
 
         let printer = CodeFragmentPrinter()
-        printer.write("\(function.name)(\(function.parameters.map { $0.name }.joined(separator: ", "))) {")
+        printer.write("\(function.name)(\(DefaultValueUtils.formatParameterList(function.parameters))) {")
         printer.indent {
             thunkBuilder.renderFunctionBody(into: printer, returnExpr: returnExpr)
         }
@@ -1891,7 +1891,7 @@ extension BridgeJSLink {
 
         let methodPrinter = CodeFragmentPrinter()
         methodPrinter.write(
-            "\(method.name): function(\(method.parameters.map { $0.name }.joined(separator: ", "))) {"
+            "\(method.name): function(\(DefaultValueUtils.formatParameterList(method.parameters))) {"
         )
         methodPrinter.indent {
             thunkBuilder.renderFunctionBody(into: methodPrinter, returnExpr: returnExpr)
@@ -2932,8 +2932,12 @@ extension BridgeJSLink {
                             printer.write("class \(klass.name) {")
                             printer.indent {
                                 if let constructor = klass.constructor {
+                                    let paramSignatures = constructor.parameters.map { param in
+                                        let optional = param.hasDefault ? "?" : ""
+                                        return "\(param.name)\(optional): \(param.type.tsType)"
+                                    }
                                     let constructorSignature =
-                                        "constructor(\(constructor.parameters.map { "\($0.name): \($0.type.tsType)" }.joined(separator: ", ")));"
+                                        "constructor(\(paramSignatures.joined(separator: ", ")));"
                                     printer.write(constructorSignature)
                                 }
 
diff --git a/Plugins/BridgeJS/Tests/BridgeJSToolTests/__Snapshots__/BridgeJSLinkTests/DefaultParameters.js b/Plugins/BridgeJS/Tests/BridgeJSToolTests/__Snapshots__/BridgeJSLinkTests/DefaultParameters.js
index a865882ef..b514a50f8 100644
--- a/Plugins/BridgeJS/Tests/BridgeJSToolTests/__Snapshots__/BridgeJSLinkTests/DefaultParameters.js
+++ b/Plugins/BridgeJS/Tests/BridgeJSToolTests/__Snapshots__/BridgeJSLinkTests/DefaultParameters.js
@@ -612,7 +612,7 @@ export async function createInstantiator(options, swift) {
                         const structValue = structHelpers.MathOperations.lift();
                         return structValue;
                     },
-                    subtract: function(a, b) {
+                    subtract: function(a, b = 5.0) {
                         const ret = instance.exports.bjs_MathOperations_static_subtract(a, b);
                         return ret;
                     },
diff --git a/Tests/BridgeJSRuntimeTests/Generated/JavaScript/BridgeJS.json b/Tests/BridgeJSRuntimeTests/Generated/JavaScript/BridgeJS.json
index 2c2d3dc0f..8a66705fc 100644
--- a/Tests/BridgeJSRuntimeTests/Generated/JavaScript/BridgeJS.json
+++ b/Tests/BridgeJSRuntimeTests/Generated/JavaScript/BridgeJS.json
@@ -13108,6 +13108,11 @@
                 }
               },
               {
+                "defaultValue" : {
+                  "double" : {
+                    "_0" : 5
+                  }
+                },
                 "label" : "b",
                 "name" : "b",
                 "type" : {
diff --git a/Tests/BridgeJSRuntimeTests/StructAPIs.swift b/Tests/BridgeJSRuntimeTests/StructAPIs.swift
index 6c0079dd1..0a05a517d 100644
--- a/Tests/BridgeJSRuntimeTests/StructAPIs.swift
+++ b/Tests/BridgeJSRuntimeTests/StructAPIs.swift
@@ -118,7 +118,7 @@ import JavaScriptKit
         return a * b
     }
 
-    @JS static func subtract(a: Double, b: Double) -> Double {
+    @JS static func subtract(a: Double, b: Double = 5.0) -> Double {
         return a - b
     }
 }
diff --git a/Tests/prelude.mjs b/Tests/prelude.mjs
index 86a5fe04f..9e32f1d26 100644
--- a/Tests/prelude.mjs
+++ b/Tests/prelude.mjs
@@ -975,6 +975,7 @@ function testStructSupport(exports) {
     assert.deepEqual(exports.roundTripAdvancedConfig(advancedConfig2), advancedConfig2);
 
     assert.equal(exports.MathOperations.subtract(10.0, 4.0), 6.0);
+    assert.equal(exports.MathOperations.subtract(10.0), 5.0);
     const mathOps = exports.MathOperations.init();
     assert.equal(mathOps.baseValue, 0.0);
     assert.equal(mathOps.add(5.0, 3.0), 8.0);