thanks for your pointer I now have it working thus: int currentline = rtxtResults.GetLineFromCharIndex(rtxtResults.Find(texttofind)); int firstcharinline = rtxtResults.GetFirstCharIndexFromLine(currentline); int lastcharonline = firstcharinline + rtxtResults.Lines[currentline].Length; rtxtResults.Select(rtxtResults.Find(nexttextofind, firstcharinline, lastcharonline, RichTextBoxFinds.None), nexttextofind.lenght); Thanks