diff --git a/spec/index.js b/spec/index.js
index 3c25872..07d647a 100644
--- a/spec/index.js
+++ b/spec/index.js
@@ -91,6 +91,14 @@ describe("Node-Passkit-generator", function () {
 			expect(noTimeZoneDateTime).toBe("2021-04-10T00:00:00");
 		});
 
+		it("A date as a Date object will apply changes", () => {
+			pass.expiration(new Date(2020,5,1,0,0,0));
+			// this is made to avoid problems with winter and summer time:
+			// we focus only on the date and time for the tests.
+			let noTimeZoneDateTime = pass._props["expirationDate"].split("+")[0];
+			expect(noTimeZoneDateTime).toBe("2020-06-01T00:00:00");
+		});
+
 		it("An invalid date, will not apply changes", () => {
 			pass.expiration("32/18/228317");
 			expect(pass._props["expirationDate"]).toBe(undefined);
@@ -125,6 +133,14 @@ describe("Node-Passkit-generator", function () {
 				let noTimeZoneDateTime = pass._props["relevantDate"].split("+")[0];
 				expect(noTimeZoneDateTime).toBe("2021-04-10T00:00:00");
 			});
+
+			it("A date as a Date object will apply changes", () => {
+				pass.relevance("relevantDate",new Date(2020,5,1,0,0,0));
+				// this is made to avoid problems with winter and summer time:
+				// we focus only on the date and time for the tests.
+				let noTimeZoneDateTime = pass._props["relevantDate"].split("+")[0];
+				expect(noTimeZoneDateTime).toBe("2020-06-01T00:00:00");
+			});			
 		});
 
 		describe("relevance('maxDistance')", () => {
diff --git a/src/pass.js b/src/pass.js
index c6a802d..437e852 100644
--- a/src/pass.js
+++ b/src/pass.js
@@ -259,7 +259,7 @@ class Pass {
 	 */
 
 	expiration(date, format) {
-		if (typeof date !== "string") {
+		if (typeof date !== "string" && !(date instanceof Date)) {
 			return this;
 		}
 
@@ -327,6 +327,11 @@ class Pass {
 
 			return assignLength(Number(!cond), this);
 		} else if (type === "relevantDate") {
+			if (typeof data !== "string" && !(data instanceof Date)) {
+				genericDebug(formatMessage("DATE_FORMAT_UNMATCH", "Relevant Date"));
+				return this;
+			}
+			
 			let dateParse = dateToW3CString(data, relevanceDateFormat);
 
 			if (!dateParse) {
diff --git a/src/utils.js b/src/utils.js
index 56a1aeb..61c7504 100644
--- a/src/utils.js
+++ b/src/utils.js
@@ -34,11 +34,11 @@ function isValidRGB(value) {
  */
 
 function dateToW3CString(date, format) {
-	if (typeof date !== "string") {
+	if (typeof date !== "string" && !(date instanceof Date)) {
 		return "";
 	}
 
-	const parsedDate = moment(date.replace(/\//g, "-"), format || ["MM-DD-YYYY hh:mm:ss", "DD-MM-YYYY hh:mm:ss"]).format();
+	const parsedDate = date instanceof Date ? moment(date).format() : moment(date.replace(/\//g, "-"), format || ["MM-DD-YYYY hh:mm:ss", "DD-MM-YYYY hh:mm:ss"]).format();
 
 	if (parsedDate === "Invalid date") {
 		return undefined;