diff --git a/types/luxon/index.d.ts b/types/luxon/index.d.ts
index d90ba90b13..94623c5abb 100644
--- a/types/luxon/index.d.ts
+++ b/types/luxon/index.d.ts
@@ -208,6 +208,7 @@ declare module 'luxon' {
             toLocaleParts(options?: DateTimeFormatOptions): any[];
             toLocaleString(options?: DateTimeFormatOptions): string;
             toObject(options?: { includeConfig?: boolean }): DateObject;
+            toMillis(): number;
             toRFC2822(): string;
             toSQL(options?: Object): string;
             toSQLDate(): string;
diff --git a/types/luxon/luxon-tests.ts b/types/luxon/luxon-tests.ts
index ce9d09ac8f..4396e8d7a2 100644
--- a/types/luxon/luxon-tests.ts
+++ b/types/luxon/luxon-tests.ts
@@ -54,6 +54,8 @@ DateTime.utc();
 DateTime.local().toUTC();
 DateTime.utc().toLocal();
 
+DateTime.fromMillis(1527780819458).toMillis();
+
 /* Duration */
 const dur = Duration.fromObject({ hours: 2, minutes: 7 });
 dt.plus(dur);