Dawn100 Minto

Hello, My husband is a sole trader and is working for a client on a freelance basis. He regularly posts parcels for the client and pays for the postage. He invoices the client at the end of each month for the postage and also the hours he has worked. He scans in the postage receipts and submits the originals paper copies to the client with his invoice. My questions are, 1) when doing his tax return this year, will these postage costs be classed as an expense, and thus be tax free? 2) does it matter that the original receipts are held by the client and he only keeps the digital copy? Thanks for your help,