Expense reports are the same failure every month: you photograph twenty to sixty receipts, open the expense tool, and the upload either times out or rejects the files for exceeding a per-file or per-report limit. Most platforms sit between 5MB and 10MB per attachment and cap the batch well below what a month of phone photos weighs. The receipts are all small text on flat paper, so the compression headroom is huge — you can take the whole set down 70-85% with the amounts still clearly readable. Compress the batch locally, export one ZIP, and the report goes through on the first attempt. Expense tools vary in what they accept, so keep a JPEG copy of each receipt after compressing. Nearly every platform takes JPEG, and none of them will reject a file for being too small.