diff --git a/src/js/rrule_datetime.rs b/src/js/rrule_datetime.rs
index 6fddbe8..9c7001f 100644
--- a/src/js/rrule_datetime.rs
+++ b/src/js/rrule_datetime.rs
@@ -89,6 +89,11 @@ impl RRuleDateTime {
     self.date_time.to_string()
   }
 
+  #[napi(js_name = "toRFC3339")]
+  pub fn to_rfc3339(&self) -> String {
+    self.date_time.to_rfc3339()
+  }
+
   #[napi(ts_return_type = "Date")]
   pub fn to_date(&self, env: Env) -> napi::Result<napi::JsDate> {
     env.create_date(self.date_time.timestamp_millis() as f64)
diff --git a/tests/datetime.spec.ts b/tests/datetime.spec.ts
index 94ff160..cda08d2 100644
--- a/tests/datetime.spec.ts
+++ b/tests/datetime.spec.ts
@@ -5,8 +5,9 @@ test.each([new Date(873205200000), 873205200000])(
   (input) => {
     const rruleDateTime = new RRuleDateTime(input, 'US/Eastern');
 
-    expect(rruleDateTime.toString()).toBe('1997-09-02 09:00:00 EDT');
     expect(rruleDateTime.toDate()).toEqual(new Date(873205200000));
+    expect(rruleDateTime.toString()).toBe('1997-09-02 09:00:00 EDT');
+    expect(rruleDateTime.toRFC3339()).toBe('1997-09-02T09:00:00-04:00');
     expect(rruleDateTime.timestamp).toBe(873205200000);
     expect(rruleDateTime.timezone.isLocal).toBe(false);
     expect(rruleDateTime.timezone.name).toBe('US/Eastern');