The Senior Deputy Speaker has asked me, as Chair of the Services Committee, to respond on his behalf. In total, 1,254,748 items of mail were received on the Parliamentary Estate in 2019. The destination of mail is not recorded but it is estimated that approximately 15 per cent of these items were destined for the House of Lords. These figures do not include parcels, courier items or internal mail.
Please note that this figure refers to the whole Parliamentary Estate, not just the Palace of Westminster.