Its not a matter of having receipts, its a matter of whether or not you will be in a position to justify the deductions you include. You should not include anything that you might have a problem justifying if challenged later on. Of course this is arbitrary as this will depend mostly on your own circumstances and those of your business. This applies to all overheads not just those in sundry expenses. If this confuses you, then perhaps you need professional advice before finalising your return, even if this means being late.