diff --git a/beamline_editor/table_utils.py b/beamline_editor/table_utils.py
index d9217dc..b712d68 100644
--- a/beamline_editor/table_utils.py
+++ b/beamline_editor/table_utils.py
@@ -910,3 +910,159 @@ def populate_table_comparison(
 
     header.reset_filters()
     table.setUpdatesEnabled(True)
+
+
+# ── Excel export ──────────────────────────────────────────────────────────────
+
+def export_table_to_excel(
+    table:      QTableWidget,
+    file_path:  str,
+    sheet_name: str,
+    include_hidden_rows: bool = False,
+) -> bool:
+    """
+    Write the visible contents of *table* to an Excel file, preserving the
+    row background colours and bold fonts used in the widget.
+
+    Nothing is written when the table has no rows (or no visible rows) —
+    the function returns False in that case and leaves any existing file
+    untouched.
+
+    Parameters
+    ----------
+    table : QTableWidget
+        The table to export.  Header labels become the first sheet row.
+    file_path : str
+        Destination .xlsx path.  Created if missing, overwritten if present.
+    sheet_name : str
+        Name of the worksheet tab inside the workbook.
+    include_hidden_rows : bool
+        When False (default) rows hidden by column filters are skipped, so
+        the export matches exactly what the user sees.  When True every row
+        is written regardless of filter state.
+
+    Returns
+    -------
+    bool
+        True  — file written (table had at least one exported row).
+        False — nothing written (table was empty / fully filtered out).
+
+    Raises
+    ------
+    ImportError
+        If openpyxl is not installed.
+
+    Notes
+    -----
+    - Cell background colours are taken from each QTableWidgetItem's
+      background brush, so the same _GROUP_COLORS palette used on screen
+      is reproduced in the workbook.
+    - Cells rendered in bold on screen (e.g. differing values or the
+      "New Element" / "Difference" / "Unresolved Element" comments) are
+      written in bold too.
+    - Numeric-looking strings are written as numbers so Excel can sort
+      and chart them; everything else is written as text.
+    """
+    try:
+        from openpyxl            import Workbook
+        from openpyxl.styles     import Font, PatternFill, Alignment, Border, Side
+        from openpyxl.utils      import get_column_letter
+    except ImportError:
+        raise ImportError(
+            "openpyxl is required for Excel export: pip install openpyxl"
+        ) from None
+
+    n_rows = table.rowCount()
+    n_cols = table.columnCount()
+    if n_rows == 0 or n_cols == 0:
+        return False
+
+    # Determine which rows to export
+    export_rows = [
+        r for r in range(n_rows)
+        if include_hidden_rows or not table.isRowHidden(r)
+    ]
+    if not export_rows:
+        return False
+
+    wb = Workbook()
+    ws = wb.active
+    ws.title = sheet_name
+
+    # ── header row ────────────────────────────────────────────────────────────
+    header_font = Font(name="Arial", size=10, bold=True, color="FFFFFFFF")
+    header_fill = PatternFill("solid", fgColor="FF404040")
+    thin        = Side(style="thin", color="FFBFBFBF")
+    border      = Border(left=thin, right=thin, top=thin, bottom=thin)
+
+    for col in range(n_cols):
+        hdr_item = table.horizontalHeaderItem(col)
+        label    = hdr_item.text() if hdr_item is not None else f"Column {col+1}"
+        cell = ws.cell(row=1, column=col + 1, value=label)
+        cell.font      = header_font
+        cell.fill      = header_fill
+        cell.alignment = Alignment(horizontal="center", vertical="center")
+        cell.border    = border
+
+    # ── data rows ─────────────────────────────────────────────────────────────
+    def _argb(qcolor) -> str | None:
+        """Convert a QColor to an openpyxl ARGB hex string, or None if white."""
+        if qcolor is None or not qcolor.isValid():
+            return None
+        # Skip pure white / fully transparent — leave the cell unfilled
+        if qcolor.alpha() == 0:
+            return None
+        if (qcolor.red(), qcolor.green(), qcolor.blue()) == (255, 255, 255):
+            return None
+        return f"FF{qcolor.red():02X}{qcolor.green():02X}{qcolor.blue():02X}"
+
+    for out_row, src_row in enumerate(export_rows, start=2):
+        for col in range(n_cols):
+            item = table.item(src_row, col)
+            text = item.text() if item is not None else ""
+
+            # Write numbers as numbers so Excel can sort/plot them
+            value: Any = text
+            if text not in ("", "-"):
+                try:
+                    if "/" not in text:          # skip "a / b" diff strings
+                        value = float(text)
+                        if value.is_integer() and "." not in text:
+                            value = int(value)
+                except (ValueError, TypeError):
+                    value = text
+
+            cell = ws.cell(row=out_row, column=col + 1, value=value)
+            cell.border = border
+
+            if item is not None:
+                # Background colour
+                argb = _argb(item.background().color())
+                if argb:
+                    cell.fill = PatternFill("solid", fgColor=argb)
+                # Bold font
+                is_bold  = item.font().bold()
+                cell.font = Font(name="Arial", size=10, bold=is_bold,
+                                 color="FF000000")
+            else:
+                cell.font = Font(name="Arial", size=10, color="FF000000")
+
+    # ── column widths ─────────────────────────────────────────────────────────
+    for col in range(n_cols):
+        max_len = 0
+        hdr_item = table.horizontalHeaderItem(col)
+        if hdr_item is not None:
+            max_len = len(hdr_item.text())
+        for src_row in export_rows:
+            item = table.item(src_row, col)
+            if item is not None:
+                max_len = max(max_len, len(item.text()))
+        ws.column_dimensions[get_column_letter(col + 1)].width = min(
+            max(10, max_len + 3), 40
+        )
+
+    # Freeze the header row so it stays visible while scrolling
+    ws.freeze_panes = "A2"
+
+    wb.save(file_path)
+    return True
diff --git a/main.py b/main.py
index 60a9986..47dc813 100644
--- a/main.py
+++ b/main.py
@@ -8,7 +8,7 @@ from PyQt5 import QtWidgets
 
 from ui.BeamlineGUI import Ui_BeamlineGUI
 from beamline_editor import BeamlineEditorWidget
-from beamline_editor.table_utils import populate_table, populate_table_comparison
+from beamline_editor.table_utils import populate_table, populate_table_comparison, export_table_to_excel
 from beamline_editor.excel_utils import read_excel_sheet
 from beamline_editor.checkbox_table import (
     populate_checkbox_table,
@@ -54,6 +54,7 @@ class BeamlineEditor(QtWidgets.QMainWindow, Ui_BeamlineGUI):
         self.actionLoad.triggered.connect(self.load)
 
         self.actionCompareLayout.triggered.connect(self.compareLayout)
+        self.actionExport_as_Proto_List.triggered.connect(self.exportLayoutasPL)
         self.actionExportOnlineModel.triggered.connect(self.exportOnlineModel)
 
         # elements, lines and branch points
@@ -193,6 +194,10 @@ class BeamlineEditor(QtWidgets.QMainWindow, Ui_BeamlineGUI):
             self.exporter.writeDomain(references[sec],sec,domain.LengthRes,subsec)
         self.exporter.buildCaseFooter()
 
+    def exportLayoutasPL(self):
+        ok = export_table_to_excel(self.UIProtoList,"Protolist/Export/protolist.xlsx","Proto-HL")
+        if not ok:
+            print("Table is empty — nothing exported")
 
     def compareLayout(self):
         if len(self.plrecs) == 0: