diff --git a/src/Bundle.js b/src/Bundle.js
index 83ee975..b70dd39 100644
--- a/src/Bundle.js
+++ b/src/Bundle.js
@@ -65,6 +65,16 @@ export default class Bundle {
 		return this.fetchModule( this.entryPath, null )
 			.then( entryModule => {
 				this.entryModule = entryModule;
+
+				if ( entryModule.exports.default ) {
+					let defaultExportName = makeLegalIdentifier( basename( this.entryPath ).slice( 0, -extname( this.entryPath ).length ) );
+					while ( entryModule.ast._scope.contains( defaultExportName ) ) {
+						defaultExportName = `_${defaultExportName}`;
+					}
+
+					entryModule.suggestName( 'default', defaultExportName );
+				}
+
 				return entryModule.expandAllStatements( true );
 			})
 			.then( statements => {
@@ -174,7 +184,7 @@ export default class Bundle {
 		const namespaceBlock = this.internalNamespaceModules.map( module => {
 			const exportKeys = keys( module.exports );
 
-			return `var ${module.suggestedNames['*']} = {\n` +
+			return `var ${module.getCanonicalName('*')} = {\n` +
 				exportKeys.map( key => `${indentString}get ${key} () { return ${module.getCanonicalName(key)}; }` ).join( ',\n' ) +
 			`\n};\n\n`;
 		}).join( '' );
diff --git a/src/Module.js b/src/Module.js
index 121001a..678ffe8 100644
--- a/src/Module.js
+++ b/src/Module.js
@@ -219,7 +219,10 @@ export default class Module {
 					importDeclaration.module = module;
 
 					if ( importDeclaration.name === 'default' ) {
-						module.suggestName( 'default', importDeclaration.localName );
+						// TODO this seems ropey
+						const localName = importDeclaration.localName;
+						const suggestion = has( this.suggestedNames, localName ) ? this.suggestedNames[ localName ] : localName;
+						module.suggestName( 'default', suggestion );
 					}
 
 					if ( module.isExternal ) {
diff --git a/src/finalisers/cjs.js b/src/finalisers/cjs.js
index 9dd2bda..57d4280 100644
--- a/src/finalisers/cjs.js
+++ b/src/finalisers/cjs.js
@@ -26,7 +26,7 @@ export default function cjs ( bundle, magicString, exportMode ) {
 
 	let exportBlock;
 	if ( exportMode === 'default' && bundle.entryModule.exports.default ) {
-		exportBlock = `module.exports = ${bundle.entryModule.suggestedNames.default};`;
+		exportBlock = `module.exports = ${bundle.entryModule.getCanonicalName('default')};`;
 	} else if ( exportMode === 'named' ) {
 		exportBlock = keys( bundle.entryModule.exports )
 			.map( key => {