diff --git a/Documentation/NamingTemplates.md b/Documentation/NamingTemplates.md
index 184570ea..b364fa04 100644
--- a/Documentation/NamingTemplates.md
+++ b/Documentation/NamingTemplates.md
@@ -105,13 +105,13 @@ As an example, this folder template will place all Liberated podcasts into a "Po
 ## Series Formatters
 |Formatter|Description|Example Usage|Example Result|
 |-|-|-|-|
-|\{N \| # \| ID\}|Formats the series using<br>the series part tags.<br>\{N\} = Series Name<br>\{#\} = Number order in series<br>\{ID\} = Audible Series ID<br><br>Default is \{N\}|`<first series>`<hr>`<first series[{N}]>`<hr>`<first series[{N}, {#}, {ID}]>`|Sherlock Holmes<hr>Sherlock Holmes<hr>Sherlock Holmes, 1, B08376S3R2|
+|\{N \| # \| ID\}|Formats the series using<br>the series part tags.<br>\{N\} = Series Name<br>\{#\} = Number order in series<br>\{#:[Number_Formatter](#number-formatters)\} = Number order in series, formatted<br>\{ID\} = Audible Series ID<br><br>Default is \{N\}|`<first series>`<hr>`<first series[{N}]>`<hr>`<first series[{N}, {#}, {ID}]>`<hr>`<first series[{N}, {ID}, {#:00.0}]>`|Sherlock Holmes<hr>Sherlock Holmes<hr>Sherlock Holmes, 1-6, B08376S3R2<hr>Sherlock Holmes, B08376S3R2, 01.0-06.0|
 
 ## Series List Formatters
 |Formatter|Description|Example Usage|Example Result|
 |-|-|-|-|
 |separator()|Speficy the text used to join<br>multiple series names.<br><br>Default is ", "|`<series[separator(; )]>`|Sherlock Holmes; Some Other Series|
-|format(\{N \| # \| ID\})|Formats the series properties<br>using the name series tags.<br>See [Series Formatter Usage](#series-formatters) above.|`<series[format({N}, {#})`<br>`separator(; )]>`<hr>`<author[format({L}, {ID}) separator(; )]>`|Sherlock Holmes, 1; Some Other Series, 1<hr>herlock Holmes, B08376S3R2; Some Other Series, B000000000|
+|format(\{N \| # \| ID\})|Formats the series properties<br>using the name series tags.<br>See [Series Formatter Usage](#series-formatters) above.|`<series[format({N}, {#})`<br>`separator(; )]>`<hr>`<series[format({ID}-{N}, {#:00.0})]>`|Sherlock Holmes, 1-6; Book Collection, 1<hr>B08376S3R2-Sherlock Holmes, 01.0-06.0, B000000000-Book Collection, 01.0|
 |max(#)|Only use the first # of series<br><br>Default is all series|`<series[max(1)]>`|Sherlock Holmes|
 
 ## Name Formatters
diff --git a/Source/FileLiberator/DownloadOptions.cs b/Source/FileLiberator/DownloadOptions.cs
index 0b761f6a..578c8ff5 100644
--- a/Source/FileLiberator/DownloadOptions.cs
+++ b/Source/FileLiberator/DownloadOptions.cs
@@ -26,7 +26,7 @@ namespace FileLiberator
 		public string Language => LibraryBook.Book.Language;
 		public string? AudibleProductId => LibraryBookDto.AudibleProductId;
 		public string? SeriesName => LibraryBookDto.FirstSeries?.Name;
-		public string? SeriesNumber => LibraryBookDto.FirstSeries?.Number;
+		public string? SeriesNumber => LibraryBookDto.FirstSeries?.Order?.ToString();
 		public NAudio.Lame.LameConfig? LameConfig { get; }
 		public string UserAgent => AudibleApi.Resources.Download_User_Agent;
 		public bool StripUnabridged => Config.AllowLibationFixup && Config.StripUnabridged;
diff --git a/Source/LibationFileManager/Templates/SeriesDto.cs b/Source/LibationFileManager/Templates/SeriesDto.cs
index cfd3d3fd..a2d7a867 100644
--- a/Source/LibationFileManager/Templates/SeriesDto.cs
+++ b/Source/LibationFileManager/Templates/SeriesDto.cs
@@ -1,27 +1,34 @@
 using System;
+using System.Text.RegularExpressions;
 
 #nullable enable
 namespace LibationFileManager.Templates;
 
-public record SeriesDto : IFormattable
+public partial record SeriesDto : IFormattable
 {
 	public string Name { get; }
 
-	public string? Number { get; }
+	public SeriesOrder Order { get; }
 	public string AudibleSeriesId { get; }
 	public SeriesDto(string name, string? number, string audibleSeriesId)
 	{
 		Name = name;
-		Number = number;
+		Order = SeriesOrder.Parse(number);
 		AudibleSeriesId = audibleSeriesId;
 	}
 
 	public override string ToString() => Name.Trim();
 	public string ToString(string? format, IFormatProvider? _)
 		=> string.IsNullOrWhiteSpace(format) ? ToString()
-		: format
-		.Replace("{N}", Name)
-		.Replace("{#}", Number?.ToString())
-		.Replace("{ID}", AudibleSeriesId)
-		.Trim();
+			: FormatRegex().Replace(format, MatchEvaluator)
+			.Replace("{N}", Name)
+			.Replace("{ID}", AudibleSeriesId)
+			.Trim();
+
+	private string MatchEvaluator(Match match)
+		=> Order?.ToString(match.Groups[1].Value, null) ?? "";
+
+	/// <summary> Format must have at least one of the string {N}, {#}, {ID} </summary>
+	[GeneratedRegex(@"{#(?:\:(.*?))?}")]
+	public static partial Regex FormatRegex();
 }
diff --git a/Source/LibationFileManager/Templates/SeriesListFormat.cs b/Source/LibationFileManager/Templates/SeriesListFormat.cs
index 1127eaa5..9db3e441 100644
--- a/Source/LibationFileManager/Templates/SeriesListFormat.cs
+++ b/Source/LibationFileManager/Templates/SeriesListFormat.cs
@@ -12,6 +12,6 @@ internal partial class SeriesListFormat : IListFormat<SeriesListFormat>
 		: IListFormat<SeriesListFormat>.Join(formatString, series);
 
 	/// <summary> Format must have at least one of the string {N}, {#}, {ID} </summary>
-	[GeneratedRegex(@"[Ff]ormat\((.*?(?:{[N#]}|{ID})+.*?)\)")]
+	[GeneratedRegex(@"[Ff]ormat\((.*?(?:{#(?:\:.*?)?}|{N}|{ID})+.*?)\)")]
 	public static partial Regex FormatRegex();
 }
diff --git a/Source/LibationFileManager/Templates/SeriesOrder.cs b/Source/LibationFileManager/Templates/SeriesOrder.cs
new file mode 100644
index 00000000..ddf31a63
--- /dev/null
+++ b/Source/LibationFileManager/Templates/SeriesOrder.cs
@@ -0,0 +1,88 @@
+using System;
+using System.Collections.Generic;
+using System.Diagnostics.CodeAnalysis;
+using System.Linq;
+
+#nullable enable
+namespace LibationFileManager.Templates;
+
+public class SeriesOrder : IFormattable
+{
+	public object[] OrderParts { get; }
+	private SeriesOrder(object[] orderParts)
+	{
+		OrderParts = orderParts;
+	}
+
+	public override string ToString() => ToString(null, null);
+
+	/// <summary>
+	/// Use float formatters to format the number parts of the order.
+	/// </summary>
+	public string ToString(string? format, IFormatProvider? formatProvider)
+		=> string.Concat(OrderParts.Select(p => p is float f ? f.ToString(format) : p.ToString())).Trim();
+
+	public static SeriesOrder Parse(string? order)
+	{
+		List<object> parts = new();
+		while (TryParseNumber(order, out var value, out var range))
+		{
+			var prefix = order[..range.Start.Value];
+			if(!string.IsNullOrWhiteSpace(prefix))
+				parts.Add(prefix);
+
+			parts.Add(value);
+
+			order = order[range.End.Value..];
+		}
+
+		if (!string.IsNullOrWhiteSpace(order))
+			parts.Add(order);
+
+		return new(parts.ToArray());
+	}
+
+	/// <summary>
+	/// Try to parse any positive number from within the string (greedy).
+	/// </summary>
+	/// <param name="numString">the string to search for a numeric value</param>
+	/// <param name="value">If this function succeeds, the number that was found; otherwise zero.</param>
+	/// <param name="range">If this function succeeds, the range of characters representing <paramref name="value"/> in <paramref name="numString"/>; otherwise default</param>
+	/// <returns>True if a number was found; otherwise false.</returns>
+	private static bool TryParseNumber([NotNullWhen(true)] string? numString, out float value, out Range range)
+	{
+		value = 0;
+		if (string.IsNullOrWhiteSpace(numString))
+		{
+			range = default;
+			return false;
+		}
+
+		for (int s = 0; s < numString.Length; s++)
+		{
+			//Assume any valid number will begin with a digit.
+			//This way, leading dots and dashes will never be considered part of a number, so
+			//no negative series numbers and no fractional series numbers < 1 (unless preceded with a '0').
+			if (!char.IsDigit(numString[s]))
+				continue;
+
+			for (int e = numString.Length; e > s; e--)
+			{
+				//The float parser will succeed with trailing whitespace,
+				//but we want to preserve it in the final display string.
+				if (char.IsWhiteSpace(numString[e - 1]))
+					continue;
+
+				var substring = numString[s..e];
+				if (float.TryParse(substring, out value))
+				{
+					range = new Range(s, e);
+					return true;
+				}
+			}
+		}
+
+		range = default;
+		return false;
+	}
+}
diff --git a/Source/LibationFileManager/Templates/Templates.cs b/Source/LibationFileManager/Templates/Templates.cs
index 5b36ae1a..e67acd6f 100644
--- a/Source/LibationFileManager/Templates/Templates.cs
+++ b/Source/LibationFileManager/Templates/Templates.cs
@@ -271,7 +271,7 @@ namespace LibationFileManager.Templates
 			{ TemplateTags.FirstNarrator, lb => lb.FirstNarrator, FormattableFormatter },
 			{ TemplateTags.Series, lb => lb.Series, SeriesListFormat.Formatter },
 			{ TemplateTags.FirstSeries, lb => lb.FirstSeries, FormattableFormatter },
-			{ TemplateTags.SeriesNumber, lb => lb.FirstSeries?.Number },
+			{ TemplateTags.SeriesNumber, lb => lb.FirstSeries?.Order, FormattableFormatter },
 			{ TemplateTags.Language, lb => lb.Language },
 			//Don't allow formatting of LanguageShort
 			{ TemplateTags.LanguageShort, lb =>lb.Language, getLanguageShort },
diff --git a/Source/_Tests/LibationFileManager.Tests/TemplatesTests.cs b/Source/_Tests/LibationFileManager.Tests/TemplatesTests.cs
index cb853d15..15da05ea 100644
--- a/Source/_Tests/LibationFileManager.Tests/TemplatesTests.cs
+++ b/Source/_Tests/LibationFileManager.Tests/TemplatesTests.cs
@@ -388,6 +388,7 @@ namespace TemplatesTests
 		[DataRow("<first series>", "Series A")]
 		[DataRow("<first series[]>", "Series A")]
 		[DataRow("<first series[{N}, {#}, {ID}]>", "Series A, 1, B1")]
+		[DataRow("<first series[{N}, {#:00.0}]>", "Series A, 01.0")]
 		public void SeriesFormat_formatters(string template, string expected)
 		{
 			var bookDto = GetLibraryBook();
@@ -406,6 +407,30 @@ namespace TemplatesTests
 				.Should().Be(expected);
 		}
 
+		[TestMethod]
+		[DataRow("<first series[{#}]>", "1-6", "1-6")]
+		[DataRow("<series[format({#:F2})]>", "1-6", "1.00-6.00")]
+		[DataRow("<first series[{#:F2}]>", "1-6", "1.00-6.00")]
+		[DataRow("<series#[F2]>", "1-6", "1.00-6.00")]
+		[DataRow("<series#[F2]>", "front 1-6 back", "front 1.00-6.00 back")]
+		[DataRow("<series#[F2]>", "front    1 - 6    back", "front 1.00 - 6.00 back")]
+		[DataRow("<series#[F2]>", "f.1", "f.1.00")]
+		[DataRow("<series#[F2]>", "f1g", "f1.00g")]
+		[DataRow("<series#[F2]>", "   f1g   ", "f1.00g")]
+		[DataRow("<series#[]>", "1", "1")]
+		[DataRow("<series#>", "1", "1")]
+		public void SeriesOrder_formatters(string template, string seriesOrder, string expected)
+		{
+			var bookDto = GetLibraryBook();
+			bookDto.Series = [new("Series A", seriesOrder,  "B1")];
+
+			Templates.TryGetTemplate<Templates.FileTemplate>(template, out var fileTemplate).Should().BeTrue();
+			fileTemplate
+				.GetFilename(bookDto, "", "", Replacements)
+				.PathWithoutPrefix
+				.Should().Be(expected);
+		}
+
 		[TestMethod]
 		[DataRow(@"C:\a\b", @"C:\a\b\foobar.ext", PlatformID.Win32NT)]
 		[DataRow(@"/a/b", @"/a/b/foobar.ext", PlatformID.Unix)]
@@ -496,7 +521,7 @@ namespace Templates_Other
 			var sb = new System.Text.StringBuilder();
 			sb.Append('0', 300);
 			var longText = sb.ToString();
-			Assert.ThrowsException<PathTooLongException>(() => NEW_GetValidFilename_FileNamingTemplate(baseDir, template, "my: book " + longText, "txt"));
+			Assert.ThrowsExactly<PathTooLongException>(() => NEW_GetValidFilename_FileNamingTemplate(baseDir, template, "my: book " + longText, "txt"));
 		}
 
 		private class TemplateTag : ITemplateTag