My solution is not the first; however, I think, it is rather universal and very short - less than 20 lines of the code. The algorithm is simple: to bypass all the rows, starting from the second at the bottom, to the top. If a cell value is the same as a value in the previous (lower) row, then increase RowSpan and make the lower cell invisible, and so forth. The code that merges the cells is very short: public class GridDecorator { public static void MergeRows(GridView gridView) { for (int rowIndex = gridView.Rows.Count - 2; rowIndex >= 0; rowIndex--) { GridViewRow row = gridView.Rows[rowIndex]; GridViewRow previousRow = gridView.Rows[rowIndex + 1]; for (int i = 0; i < row.Cells.Count; i++) { if (row.Cells[i].Text == previousRow.Cells[i].Text) { row.Cells[i].RowSpan = previousRow.Cells[i].RowSpan < 2 ? 2 :