diff --git a/CHANGELOG.md b/CHANGELOG.md
index 18acc97..de00752 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -9,6 +9,7 @@ and this project adheres to [Semantic Versioning](http://semver.org/spec/v2.0.0.
 ### Added
  - IcdEnvironment.GetUtcTime() to get UTC representaiton of current time.
  - Extension methods for determining if a sequence is in order
+ - Overload for calculating the modulus of longs
 
 ## [9.9.0] - 2019-09-16
 ### Added
diff --git a/ICD.Common.Utils/MathUtils.cs b/ICD.Common.Utils/MathUtils.cs
index e81584a..4143d68 100644
--- a/ICD.Common.Utils/MathUtils.cs
+++ b/ICD.Common.Utils/MathUtils.cs
@@ -216,11 +216,24 @@ namespace ICD.Common.Utils
 		/// <param name="number"></param>
 		/// <param name="mod"></param>
 		/// <returns></returns>
-		/// <remarks>method name can't be "Mod", due to S+ compatability issues</remarks>
+		/// <remarks>Method name can't be "Mod", due to S+ compatibility issues</remarks>
 		public static int Modulus(int number, int mod)
 		{
 			int remainder = number % mod;
 			return remainder < 0 ? remainder + mod : remainder;
 		}
+
+		/// <summary>
+		/// Calculates the modulus of the given number.
+		/// </summary>
+		/// <param name="number"></param>
+		/// <param name="mod"></param>
+		/// <returns></returns>
+		/// <remarks>Method name can't be "Mod", due to S+ compatibility issues</remarks>
+		public static long Modulus(long number, long mod)
+		{
+			long remainder = number % mod;
+			return remainder < 0 ? remainder + mod : remainder;
+		}
 	}
 }