diff --git a/moment-fquarter.js b/moment-fquarter.js
index c7dbdef..6b76b19 100644
--- a/moment-fquarter.js
+++ b/moment-fquarter.js
@@ -8,26 +8,30 @@
 
 	function onload(moment) {
 		moment.fn.fquarter = function (startMonth) {
-			var initial = this.local()._quarter || "Q";
+			var thisDate = this.clone();
+			var initial = thisDate.local()._quarter || "Q";
 			var result = {}, adjustedDate, nextYear = null;
 			startMonth = startMonth || 4; // default is April
+			var originalDate = this.clone();
 
 			if (startMonth > 1) {
-				adjustedDate = this.subtract(startMonth - 1, "months");
+				adjustedDate = thisDate.subtract(startMonth - 1, "months");
 				nextYear = adjustedDate.clone().add(1, "years");
 			} else {
-				adjustedDate = this;
+				adjustedDate = thisDate;
 			}
 			if (startMonth < 0) {
-				adjustedDate = this.subtract(12 + startMonth, "month").add(1, "year");
+				adjustedDate = thisDate.subtract(12 + startMonth, "month").add(1, "year");
 				nextYear = adjustedDate.clone().add(1, "year");
 			} else {
-				adjustedDate = this;
+				adjustedDate = thisDate;
 			}
 
 			result.quarter = Math.ceil((adjustedDate.month() + 1.0) / 3.0);
 			result.year = adjustedDate.year();
 			result.nextYear = (nextYear) ? nextYear.year() : nextYear;
+			result.start = originalDate.set("date", 1).subtract((originalDate.month()+12)%3, "months").format("YYYY-MM-DD");
+			result.end =   originalDate.set("date", 1).subtract((originalDate.month()+12)%3, "months").add(3, "months").subtract(1, "day").format("YYYY-MM-DD");
 
 			result.toString = function () {
 				var str = initial + result.quarter + " " + result.year;
diff --git a/test/fquarterSpec.coffee b/test/fquarterSpec.coffee
index 8ce9759..9c776fd 100644
--- a/test/fquarterSpec.coffee
+++ b/test/fquarterSpec.coffee
@@ -1,152 +1,157 @@
 describe "Fiscal quarters", ->
   it "Jan is Q4", ->
-    expect(moment("2013-01-01").fquarter()).toEqual({quarter: 4, year: 2012, nextYear: 2013})
+    expect(moment("2013-01-01").fquarter()).toEqual({quarter: 4, year: 2012, nextYear: 2013, start: "2013-01-01", end: "2013-03-31"})
     expect(moment("2013-01-01").fquarter().toString()).toEqual("Q4 2012/13")
   it "Feb is Q4", ->
-    expect(moment("2013-02-01").fquarter()).toEqual({quarter: 4, year: 2012, nextYear: 2013})
+    expect(moment("2013-02-01").fquarter()).toEqual({quarter: 4, year: 2012, nextYear: 2013, start: "2013-01-01", end: "2013-03-31"})
     expect(moment("2013-02-01").fquarter().toString()).toEqual("Q4 2012/13")
   it "Mar is Q4", ->
-    expect(moment("2013-03-01").fquarter()).toEqual({quarter: 4, year: 2012, nextYear: 2013})
+    expect(moment("2013-03-01").fquarter()).toEqual({quarter: 4, year: 2012, nextYear: 2013, start: "2013-01-01", end: "2013-03-31"})
     expect(moment("2013-03-01").fquarter().toString()).toEqual("Q4 2012/13")
   it "Apr is Q1", ->
-    expect(moment("2013-04-01").fquarter()).toEqual({quarter: 1, year: 2013, nextYear: 2014})
+    expect(moment("2013-04-01").fquarter()).toEqual({quarter: 1, year: 2013, nextYear: 2014, start: "2013-04-01", end: "2013-06-30"})
     expect(moment("2013-04-01").fquarter().toString()).toEqual("Q1 2013/14")
   it "May is Q1", ->
-    expect(moment("2013-05-01").fquarter()).toEqual({quarter: 1, year: 2013, nextYear: 2014})
+    expect(moment("2013-05-01").fquarter()).toEqual({quarter: 1, year: 2013, nextYear: 2014, start: "2013-04-01", end: "2013-06-30"})
     expect(moment("2013-05-01").fquarter().toString()).toEqual("Q1 2013/14")
   it "Jun is Q1", ->
-    expect(moment("2013-06-01").fquarter()).toEqual({quarter: 1, year: 2013, nextYear: 2014})
+    expect(moment("2013-06-01").fquarter()).toEqual({quarter: 1, year: 2013, nextYear: 2014, start: "2013-04-01", end: "2013-06-30"})
     expect(moment("2013-06-01").fquarter().toString()).toEqual("Q1 2013/14")
   it "Jul is Q2", ->
-    expect(moment("2013-07-01").fquarter()).toEqual({quarter: 2, year: 2013, nextYear: 2014})
+    expect(moment("2013-07-01").fquarter()).toEqual({quarter: 2, year: 2013, nextYear: 2014, start: "2013-07-01", end: "2013-09-30"})
     expect(moment("2013-07-01").fquarter().toString()).toEqual("Q2 2013/14")
   it "Aug is Q2", ->
-    expect(moment("2013-08-01").fquarter()).toEqual({quarter: 2, year: 2013, nextYear: 2014})
+    expect(moment("2013-08-01").fquarter()).toEqual({quarter: 2, year: 2013, nextYear: 2014, start: "2013-07-01", end: "2013-09-30"})
     expect(moment("2013-08-01").fquarter().toString()).toEqual("Q2 2013/14")
   it "Sep is Q2", ->
-    expect(moment("2013-09-01").fquarter()).toEqual({quarter: 2, year: 2013, nextYear: 2014})
+    expect(moment("2013-09-01").fquarter()).toEqual({quarter: 2, year: 2013, nextYear: 2014, start: "2013-07-01", end: "2013-09-30"})
     expect(moment("2013-09-01").fquarter().toString()).toEqual("Q2 2013/14")
   it "Oct is Q3", ->
-    expect(moment("2013-10-01").fquarter()).toEqual({quarter: 3, year: 2013, nextYear: 2014})
+    expect(moment("2013-10-01").fquarter()).toEqual({quarter: 3, year: 2013, nextYear: 2014, start: "2013-10-01", end: "2013-12-31"})
     expect(moment("2013-10-01").fquarter().toString()).toEqual("Q3 2013/14")
   it "Nov is Q3", ->
-    expect(moment("2013-11-01").fquarter()).toEqual({quarter: 3, year: 2013, nextYear: 2014})
+    expect(moment("2013-11-01").fquarter()).toEqual({quarter: 3, year: 2013, nextYear: 2014, start: "2013-10-01", end: "2013-12-31"})
     expect(moment("2013-11-01").fquarter().toString()).toEqual("Q3 2013/14")
   it "Dec is Q3", ->
-    expect(moment("2013-12-01").fquarter()).toEqual({quarter: 3, year: 2013, nextYear: 2014})
+    expect(moment("2013-12-01").fquarter()).toEqual({quarter: 3, year: 2013, nextYear: 2014, start: "2013-10-01", end: "2013-12-31"})
     expect(moment("2013-12-01").fquarter().toString()).toEqual("Q3 2013/14")
 
 describe "Calendar quarters", ->
   it "Jan is Q1", ->
-    expect(moment("2013-01-01").fquarter(1)).toEqual({quarter: 1, year: 2013, nextYear: null})
+    expect(moment("2013-01-01").fquarter(1)).toEqual({quarter: 1, year: 2013, nextYear: null, start: "2013-01-01", end: "2013-03-31"})
     expect(moment("2013-01-01").fquarter(1).toString()).toEqual("Q1 2013")
   it "Feb is Q1", ->
-    expect(moment("2013-02-01").fquarter(1)).toEqual({quarter: 1, year: 2013, nextYear: null})
+    expect(moment("2013-02-01").fquarter(1)).toEqual({quarter: 1, year: 2013, nextYear: null, start: "2013-01-01", end: "2013-03-31"})
     expect(moment("2013-02-01").fquarter(1).toString()).toEqual("Q1 2013")
   it "Mar is Q1", ->
-    expect(moment("2013-03-01").fquarter(1)).toEqual({quarter: 1, year: 2013, nextYear: null})
+    expect(moment("2013-03-01").fquarter(1)).toEqual({quarter: 1, year: 2013, nextYear: null, start: "2013-01-01", end: "2013-03-31"})
     expect(moment("2013-03-01").fquarter(1).toString()).toEqual("Q1 2013")
   it "Apr is Q2", ->
-    expect(moment("2013-04-01").fquarter(1)).toEqual({quarter: 2, year: 2013, nextYear: null})
+    expect(moment("2013-04-01").fquarter(1)).toEqual({quarter: 2, year: 2013, nextYear: null, start: "2013-04-01", end: "2013-06-30"})
     expect(moment("2013-04-01").fquarter(1).toString()).toEqual("Q2 2013")
   it "May is Q2", ->
-    expect(moment("2013-05-01").fquarter(1)).toEqual({quarter: 2, year: 2013, nextYear: null})
+    expect(moment("2013-05-01").fquarter(1)).toEqual({quarter: 2, year: 2013, nextYear: null, start: "2013-04-01", end: "2013-06-30"})
     expect(moment("2013-05-01").fquarter(1).toString()).toEqual("Q2 2013")
   it "Jun is Q2", ->
-    expect(moment("2013-06-01").fquarter(1)).toEqual({quarter: 2, year: 2013, nextYear: null})
+    expect(moment("2013-06-01").fquarter(1)).toEqual({quarter: 2, year: 2013, nextYear: null, start: "2013-04-01", end: "2013-06-30"})
     expect(moment("2013-06-01").fquarter(1).toString()).toEqual("Q2 2013")
   it "Jul is Q3", ->
-    expect(moment("2013-07-01").fquarter(1)).toEqual({quarter: 3, year: 2013, nextYear: null})
+    expect(moment("2013-07-01").fquarter(1)).toEqual({quarter: 3, year: 2013, nextYear: null, start: "2013-07-01", end: "2013-09-30"})
     expect(moment("2013-07-01").fquarter(1).toString()).toEqual("Q3 2013")
   it "Aug is Q3", ->
-    expect(moment("2013-08-01").fquarter(1)).toEqual({quarter: 3, year: 2013, nextYear: null})
+    expect(moment("2013-08-01").fquarter(1)).toEqual({quarter: 3, year: 2013, nextYear: null, start: "2013-07-01", end: "2013-09-30"})
     expect(moment("2013-08-01").fquarter(1).toString()).toEqual("Q3 2013")
   it "Sep is Q3", ->
-    expect(moment("2013-09-01").fquarter(1)).toEqual({quarter: 3, year: 2013, nextYear: null})
+    expect(moment("2013-09-01").fquarter(1)).toEqual({quarter: 3, year: 2013, nextYear: null, start: "2013-07-01", end: "2013-09-30"})
     expect(moment("2013-09-01").fquarter(1).toString()).toEqual("Q3 2013")
   it "Oct is Q4", ->
-    expect(moment("2013-10-01").fquarter(1)).toEqual({quarter: 4, year: 2013, nextYear: null})
+    expect(moment("2013-10-01").fquarter(1)).toEqual({quarter: 4, year: 2013, nextYear: null, start: "2013-10-01", end: "2013-12-31"})
     expect(moment("2013-10-01").fquarter(1).toString()).toEqual("Q4 2013")
   it "Nov is Q4", ->
-    expect(moment("2013-11-01").fquarter(1)).toEqual({quarter: 4, year: 2013, nextYear: null})
+    expect(moment("2013-11-01").fquarter(1)).toEqual({quarter: 4, year: 2013, nextYear: null, start: "2013-10-01", end: "2013-12-31"})
     expect(moment("2013-11-01").fquarter(1).toString()).toEqual("Q4 2013")
   it "Dec is Q4", ->
-    expect(moment("2013-12-01").fquarter(1)).toEqual({quarter: 4, year: 2013, nextYear: null})
+    expect(moment("2013-12-01").fquarter(1)).toEqual({quarter: 4, year: 2013, nextYear: null, start: "2013-10-01", end: "2013-12-31"})
     expect(moment("2013-12-01").fquarter(1).toString()).toEqual("Q4 2013")
 
 describe "Academic quarters", ->
   it "Jan is Q2", ->
-    expect(moment("2013-01-01").fquarter(9)).toEqual({quarter: 2, year: 2012, nextYear: 2013})
+    expect(moment("2013-01-01").fquarter(9)).toEqual({quarter: 2, year: 2012, nextYear: 2013, start: "2013-01-01", end: "2013-03-31"})
     expect(moment("2013-01-01").fquarter(9).toString()).toEqual("Q2 2012/13")
   it "Feb is Q2", ->
-    expect(moment("2013-02-01").fquarter(9)).toEqual({quarter: 2, year: 2012, nextYear: 2013})
+    expect(moment("2013-02-01").fquarter(9)).toEqual({quarter: 2, year: 2012, nextYear: 2013, start: "2013-01-01", end: "2013-03-31"})
     expect(moment("2013-02-01").fquarter(9).toString()).toEqual("Q2 2012/13")
   it "Mar is Q3", ->
-    expect(moment("2013-03-01").fquarter(9)).toEqual({quarter: 3, year: 2012, nextYear: 2013})
+    expect(moment("2013-03-01").fquarter(9)).toEqual({quarter: 3, year: 2012, nextYear: 2013, start: "2013-01-01", end: "2013-03-31"})
     expect(moment("2013-03-01").fquarter(9).toString()).toEqual("Q3 2012/13")
   it "Apr is Q3", ->
-    expect(moment("2013-04-01").fquarter(9)).toEqual({quarter: 3, year: 2012, nextYear: 2013})
+    expect(moment("2013-04-01").fquarter(9)).toEqual({quarter: 3, year: 2012, nextYear: 2013, start: "2013-04-01", end: "2013-06-30"})
     expect(moment("2013-04-01").fquarter(9).toString()).toEqual("Q3 2012/13")
   it "May is Q3", ->
-    expect(moment("2013-05-01").fquarter(9)).toEqual({quarter: 3, year: 2012, nextYear: 2013})
+    expect(moment("2013-05-01").fquarter(9)).toEqual({quarter: 3, year: 2012, nextYear: 2013, start: "2013-04-01", end: "2013-06-30"})
     expect(moment("2013-05-01").fquarter(9).toString()).toEqual("Q3 2012/13")
   it "Jun is Q4", ->
-    expect(moment("2013-06-01").fquarter(9)).toEqual({quarter: 4, year: 2012, nextYear: 2013})
+    expect(moment("2013-06-01").fquarter(9)).toEqual({quarter: 4, year: 2012, nextYear: 2013, start: "2013-04-01", end: "2013-06-30"})
     expect(moment("2013-06-01").fquarter(9).toString()).toEqual("Q4 2012/13")
   it "Jul is Q4", ->
-    expect(moment("2013-07-01").fquarter(9)).toEqual({quarter: 4, year: 2012, nextYear: 2013})
+    expect(moment("2013-07-01").fquarter(9)).toEqual({quarter: 4, year: 2012, nextYear: 2013, start: "2013-07-01", end: "2013-09-30"})
     expect(moment("2013-07-01").fquarter(9).toString()).toEqual("Q4 2012/13")
   it "Aug is Q4", ->
-    expect(moment("2013-08-01").fquarter(9)).toEqual({quarter: 4, year: 2012, nextYear: 2013})
+    expect(moment("2013-08-01").fquarter(9)).toEqual({quarter: 4, year: 2012, nextYear: 2013, start: "2013-07-01", end: "2013-09-30"})
     expect(moment("2013-08-01").fquarter(9).toString()).toEqual("Q4 2012/13")
   it "Sep is Q1", ->
-    expect(moment("2013-09-01").fquarter(9)).toEqual({quarter: 1, year: 2013, nextYear: 2014})
+    expect(moment("2013-09-01").fquarter(9)).toEqual({quarter: 1, year: 2013, nextYear: 2014, start: "2013-07-01", end: "2013-09-30"})
     expect(moment("2013-09-01").fquarter(9).toString()).toEqual("Q1 2013/14")
   it "Oct is Q1", ->
-    expect(moment("2013-10-01").fquarter(9)).toEqual({quarter: 1, year: 2013, nextYear: 2014})
+    expect(moment("2013-10-01").fquarter(9)).toEqual({quarter: 1, year: 2013, nextYear: 2014, start: "2013-10-01", end: "2013-12-31"})
     expect(moment("2013-10-01").fquarter(9).toString()).toEqual("Q1 2013/14")
   it "Nov is Q1", ->
-    expect(moment("2013-11-01").fquarter(9)).toEqual({quarter: 1, year: 2013, nextYear: 2014})
+    expect(moment("2013-11-01").fquarter(9)).toEqual({quarter: 1, year: 2013, nextYear: 2014, start: "2013-10-01", end: "2013-12-31"})
     expect(moment("2013-11-01").fquarter(9).toString()).toEqual("Q1 2013/14")
   it "Dec is Q2", ->
-    expect(moment("2013-12-01").fquarter(9)).toEqual({quarter: 2, year: 2013, nextYear: 2014})
+    expect(moment("2013-12-01").fquarter(9)).toEqual({quarter: 2, year: 2013, nextYear: 2014, start: "2013-10-01", end: "2013-12-31"})
     expect(moment("2013-12-01").fquarter(9).toString()).toEqual("Q2 2013/14")
 
-
 describe "Backwards Fiscal Year quarters", ->
   it "January is FYQ2 of current calendar year", ->
-    expect(moment('2015-01-01').fquarter(-3)).toEqual({quarter: 2, year: 2015, nextYear: 2016})
+    expect(moment('2015-01-01').fquarter(-3)).toEqual({quarter: 2, year: 2015, nextYear: 2016, start: "2015-01-01", end: "2015-03-31"})
     expect(moment("2015-01-01").fquarter(-3).toString()).toEqual("Q2 2015/16")
   it "February is FYQ2 of current calendar year", ->
-    expect(moment('2015-02-15').fquarter(-3)).toEqual({quarter: 2, year: 2015, nextYear: 2016})
+    expect(moment('2015-02-15').fquarter(-3)).toEqual({quarter: 2, year: 2015, nextYear: 2016, start: "2015-01-01", end: "2015-03-31"})
     expect(moment("2015-02-15").fquarter(-3).toString()).toEqual("Q2 2015/16")
   it "March is FYQ2 of current calendar year", ->
-    expect(moment('2015-03-15').fquarter(-3)).toEqual({quarter: 2, year: 2015, nextYear: 2016})
+    expect(moment('2015-03-15').fquarter(-3)).toEqual({quarter: 2, year: 2015, nextYear: 2016, start: "2015-01-01", end: "2015-03-31"})
     expect(moment("2015-03-15").fquarter(-3).toString()).toEqual("Q2 2015/16")
   it "April is FYQ3 of current calendar year", ->
-    expect(moment('2015-04-15').fquarter(-3)).toEqual({quarter: 3, year: 2015, nextYear: 2016})
+    expect(moment('2015-04-15').fquarter(-3)).toEqual({quarter: 3, year: 2015, nextYear: 2016, start: "2015-04-01", end: "2015-06-30"})
     expect(moment("2015-04-15").fquarter(-3).toString()).toEqual("Q3 2015/16")
   it "May is FYQ3 of current calendar year", ->
-    expect(moment('2015-05-15').fquarter(-3)).toEqual({quarter: 3, year: 2015, nextYear: 2016})
+    expect(moment('2015-05-15').fquarter(-3)).toEqual({quarter: 3, year: 2015, nextYear: 2016, start: "2015-04-01", end: "2015-06-30"})
     expect(moment("2015-05-15").fquarter(-3).toString()).toEqual("Q3 2015/16")
   it "June is FYQ3 of current calendar year", ->
-    expect(moment('2015-06-15').fquarter(-3)).toEqual({quarter: 3, year: 2015, nextYear: 2016})
+    expect(moment('2015-06-15').fquarter(-3)).toEqual({quarter: 3, year: 2015, nextYear: 2016, start: "2015-04-01", end: "2015-06-30"})
     expect(moment("2015-06-15").fquarter(-3).toString()).toEqual("Q3 2015/16")
   it "July is FYQ4 of current calendar year", ->
-    expect(moment('2015-07-15').fquarter(-3)).toEqual({quarter: 4, year: 2015, nextYear: 2016})
+    expect(moment('2015-07-15').fquarter(-3)).toEqual({quarter: 4, year: 2015, nextYear: 2016, start: "2015-07-01", end: "2015-09-30"})
     expect(moment("2015-07-15").fquarter(-3).toString()).toEqual("Q4 2015/16")
   it "August is FYQ4 of current calendar year", ->
-    expect(moment('2015-08-05').fquarter(-3)).toEqual({quarter: 4, year: 2015, nextYear: 2016})
+    expect(moment('2015-08-05').fquarter(-3)).toEqual({quarter: 4, year: 2015, nextYear: 2016, start: "2015-07-01", end: "2015-09-30"})
     expect(moment("2015-08-05").fquarter(-3).toString()).toEqual("Q4 2015/16")
   it "September is Q4 of current calendar year", ->
-    expect(moment('2015-09-15').fquarter(-3)).toEqual({quarter: 4, year: 2015, nextYear: 2016})
+    expect(moment('2015-09-15').fquarter(-3)).toEqual({quarter: 4, year: 2015, nextYear: 2016, start: "2015-07-01", end: "2015-09-30"})
     expect(moment("2015-09-15").fquarter(-3).toString()).toEqual("Q4 2015/16")
   it "October is Q1 of next calendar year", ->
-    expect(moment('2015-10-15').fquarter(-3)).toEqual({quarter: 1, year: 2016, nextYear: 2017})
+    expect(moment('2015-10-15').fquarter(-3)).toEqual({quarter: 1, year: 2016, nextYear: 2017, start: "2015-10-01", end: "2015-12-31"})
     expect(moment("2015-10-15").fquarter(-3).toString()).toEqual("Q1 2016/17")
   it "November is Q1 of next calendar year", ->
-    expect(moment('2015-10-15').fquarter(-3)).toEqual({quarter: 1, year: 2016, nextYear: 2017})
+    expect(moment('2015-10-15').fquarter(-3)).toEqual({quarter: 1, year: 2016, nextYear: 2017, start: "2015-10-01", end: "2015-12-31"})
     expect(moment("2015-10-15").fquarter(-3).toString()).toEqual("Q1 2016/17")
   it "December is Q1 of next calendar year", ->
-    expect(moment('2015-10-15').fquarter(-3)).toEqual({quarter: 1, year: 2016, nextYear: 2017})
+    expect(moment('2015-10-15').fquarter(-3)).toEqual({quarter: 1, year: 2016, nextYear: 2017, start: "2015-10-01", end: "2015-12-31"})
     expect(moment("2015-10-15").fquarter(-3).toString()).toEqual("Q1 2016/17")
+
+describe "Moment date should not change", ->
+  it "should not change original moment date object", ->
+    testDate = moment("2015-01-01")
+    testDate.fquarter()
+    expect(testDate.format("YYYY-MM-DD")).toEqual("2015-01-01")