diff --git a/OpenNest.Posts.Cincinnati/CincinnatiPartSubprogramWriter.cs b/OpenNest.Posts.Cincinnati/CincinnatiPartSubprogramWriter.cs
index 25a0674..f3cc40a 100644
--- a/OpenNest.Posts.Cincinnati/CincinnatiPartSubprogramWriter.cs
+++ b/OpenNest.Posts.Cincinnati/CincinnatiPartSubprogramWriter.cs
@@ -1,5 +1,6 @@
 using System.Collections.Generic;
 using System.IO;
+using System.Text;
 using OpenNest.CNC;
 using OpenNest.Geometry;
 
@@ -136,4 +137,61 @@ public sealed class CincinnatiPartSubprogramWriter
 
         return (mapping, entries);
     }
+
+    /// <summary>
+    /// Scans all parts across all plates and builds a nest-level registry of unique
+    /// hole sub-programs. Deduplicates by comparing sub-program code content.
+    /// </summary>
+    internal static (Dictionary<int, int> modelToPostMapping, List<(int subNum, Program program)> entries)
+        BuildHoleRegistry(IEnumerable<Plate> plates, int startNumber)
+    {
+        var mapping = new Dictionary<int, int>();
+        var entries = new List<(int, Program)>();
+        var contentIndex = new Dictionary<string, int>();
+        var nextSubNum = startNumber;
+
+        foreach (var plate in plates)
+        {
+            foreach (var part in plate.Parts)
+            {
+                if (part.BaseDrawing.IsCutOff) continue;
+                foreach (var code in part.Program.Codes)
+                {
+                    if (code is not SubProgramCall call) continue;
+                    if (mapping.ContainsKey(call.Id)) continue;
+
+                    var canonical = ProgramToCanonical(call.Program);
+                    if (contentIndex.TryGetValue(canonical, out var existingNum))
+                    {
+                        mapping[call.Id] = existingNum;
+                    }
+                    else
+                    {
+                        var subNum = nextSubNum++;
+                        mapping[call.Id] = subNum;
+                        contentIndex[canonical] = subNum;
+                        entries.Add((subNum, call.Program));
+                    }
+                }
+            }
+        }
+
+        return (mapping, entries);
+    }
+
+    private static string ProgramToCanonical(Program pgm)
+    {
+        var sb = new StringBuilder();
+        sb.Append(pgm.Mode == Mode.Absolute ? "A" : "I");
+        foreach (var code in pgm.Codes)
+        {
+            if (code is LinearMove lm)
+                sb.Append($"L{lm.EndPoint.X:F6},{lm.EndPoint.Y:F6},{(int)lm.Layer}");
+            else if (code is ArcMove am)
+                sb.Append($"A{am.EndPoint.X:F6},{am.EndPoint.Y:F6},{am.CenterPoint.X:F6},{am.CenterPoint.Y:F6},{(int)am.Rotation},{(int)am.Layer}");
+            else if (code is RapidMove rm)
+                sb.Append($"R{rm.EndPoint.X:F6},{rm.EndPoint.Y:F6}");
+        }
+        return sb.ToString();
+    }
 }
diff --git a/OpenNest.Posts.Cincinnati/CincinnatiPostProcessor.cs b/OpenNest.Posts.Cincinnati/CincinnatiPostProcessor.cs
index 4d508de..0699b05 100644
--- a/OpenNest.Posts.Cincinnati/CincinnatiPostProcessor.cs
+++ b/OpenNest.Posts.Cincinnati/CincinnatiPostProcessor.cs
@@ -89,9 +89,15 @@ namespace OpenNest.Posts.Cincinnati
             if (Config.UsePartSubprograms)
                 (partSubprograms, subprogramEntries) = CincinnatiPartSubprogramWriter.BuildRegistry(plates, Config.PartSubprogramStart);
 
+            // 5b. Build hole sub-program registry (SubProgramCalls across all parts)
+            var holeStartNumber = Config.PartSubprogramStart
+                + (subprogramEntries?.Count ?? 0);
+            var (holeMapping, holeEntries) = CincinnatiPartSubprogramWriter.BuildHoleRegistry(plates, holeStartNumber);
+
             // 6. Create writers
             var preamble = new CincinnatiPreambleWriter(Config);
-            var sheetWriter = new CincinnatiSheetWriter(Config, vars);
+            var sheetWriter = new CincinnatiSheetWriter(Config, vars,
+                holeMapping.Count > 0 ? holeMapping : null);
 
             // 7. Build material description from nest
             var material = nest.Material;
@@ -135,6 +141,23 @@ namespace OpenNest.Posts.Cincinnati
                 }
             }
 
+            // Hole sub-programs (SubProgramCall definitions)
+            if (holeEntries.Count > 0)
+            {
+                var holeSubWriter = new CincinnatiPartSubprogramWriter(Config);
+                var sheetDiagonal = firstPlate != null
+                    ? System.Math.Sqrt(firstPlate.Size.Width * firstPlate.Size.Width
+                        + firstPlate.Size.Length * firstPlate.Size.Length)
+                    : 100.0;
+
+                foreach (var (subNum, pgm) in holeEntries)
+                {
+                    CincinnatiPartSubprogramWriter.EnsureLeadingRapid(pgm);
+                    holeSubWriter.Write(writer, pgm, "HOLE", subNum,
+                        initialCutLibrary, etchLibrary, sheetDiagonal);
+                }
+            }
+
             writer.Flush();
         }
 
diff --git a/OpenNest.Posts.Cincinnati/CincinnatiSheetWriter.cs b/OpenNest.Posts.Cincinnati/CincinnatiSheetWriter.cs
index b2b9e9c..a8f4bc9 100644
--- a/OpenNest.Posts.Cincinnati/CincinnatiSheetWriter.cs
+++ b/OpenNest.Posts.Cincinnati/CincinnatiSheetWriter.cs
@@ -17,13 +17,16 @@ public sealed class CincinnatiSheetWriter
     private readonly ProgramVariableManager _vars;
     private readonly CoordinateFormatter _fmt;
     private readonly CincinnatiFeatureWriter _featureWriter;
+    private readonly Dictionary<int, int> _holeSubprograms;
 
-    public CincinnatiSheetWriter(CincinnatiPostConfig config, ProgramVariableManager vars)
+    public CincinnatiSheetWriter(CincinnatiPostConfig config, ProgramVariableManager vars,
+        Dictionary<int, int> holeSubprograms = null)
     {
         _config = config;
         _vars = vars;
         _fmt = new CoordinateFormatter(config.PostedAccuracy);
         _featureWriter = new CincinnatiFeatureWriter(config);
+        _holeSubprograms = holeSubprograms;
     }
 
     /// <summary>
@@ -132,11 +135,21 @@ public sealed class CincinnatiSheetWriter
                 for (var f = 0; f < features.Count; f++)
                 {
                     var (codes, isEtch) = features[f];
+                    var isLastFeature = isLastPart && f == features.Count - 1;
+
+                    // SubProgramCall features are emitted as M98 hole calls
+                    if (codes.Count == 1 && codes[0] is SubProgramCall holeCall)
+                    {
+                        WriteHoleSubprogramCall(w, holeCall, featureIndex, isLastFeature);
+                        featureIndex++;
+                        lastPartName = partName;
+                        continue;
+                    }
+
                     var featureNumber = featureIndex == 0
                         ? _config.FeatureLineNumberStart
                         : 1000 + featureIndex + 1;
 
-                    var isLastFeature = isLastPart && f == features.Count - 1;
                     var cutDistance = FeatureUtils.ComputeCutDistance(codes);
 
                     var ctx = new FeatureContext
@@ -204,6 +217,25 @@ public sealed class CincinnatiSheetWriter
             w.WriteLine("M47");
     }
 
+    private void WriteHoleSubprogramCall(TextWriter w, SubProgramCall call, int featureIndex, bool isLastFeature)
+    {
+        var postSubNum = _holeSubprograms != null && _holeSubprograms.TryGetValue(call.Id, out var num)
+            ? num : call.Id;
+
+        var featureNumber = featureIndex == 0
+            ? _config.FeatureLineNumberStart
+            : 1000 + featureIndex + 1;
+
+        var sb = new StringBuilder();
+        if (_config.UseLineNumbers)
+            sb.Append($"N{featureNumber} ");
+        sb.Append($"M98 P{postSubNum} X{_fmt.FormatCoord(call.Offset.X)} Y{_fmt.FormatCoord(call.Offset.Y)}");
+        w.WriteLine(sb.ToString());
+
+        if (!isLastFeature)
+            w.WriteLine("M47");
+    }
+
     private void WritePartsInline(TextWriter w, List<Part> allParts,
         string cutLibrary, string etchLibrary, double sheetDiagonal,
         double plateWidth, double plateLength,
@@ -228,6 +260,14 @@ public sealed class CincinnatiSheetWriter
             var isSafetyHeadraise = partName != lastPartName && lastPartName != "";
             var isLastFeature = i == features.Count - 1;
 
+            // SubProgramCall features are emitted as M98 hole calls
+            if (codes.Count == 1 && codes[0] is SubProgramCall holeCall)
+            {
+                WriteHoleSubprogramCall(w, holeCall, i, isLastFeature);
+                lastPartName = partName;
+                continue;
+            }
+
             var featureNumber = i == 0
                 ? _config.FeatureLineNumberStart
                 : 1000 + i + 1;
diff --git a/OpenNest.Posts.Cincinnati/FeatureUtils.cs b/OpenNest.Posts.Cincinnati/FeatureUtils.cs
index d31d3a2..e75b5b2 100644
--- a/OpenNest.Posts.Cincinnati/FeatureUtils.cs
+++ b/OpenNest.Posts.Cincinnati/FeatureUtils.cs
@@ -21,7 +21,16 @@ public static class FeatureUtils
 
         foreach (var code in codes)
         {
-            if (code is RapidMove)
+            if (code is SubProgramCall)
+            {
+                // Flush any pending feature
+                if (current != null)
+                    features.Add(current);
+                // SubProgramCall is its own feature
+                features.Add(new List<ICode> { code });
+                current = null;
+            }
+            else if (code is RapidMove)
             {
                 if (current != null)
                     features.Add(current);