You can actually deduct expenses if you don’t have the receipts or documentation for them … a lot of the time. A good faith estimate is acceptable. However, just because you can do this, doesn’t mean you should slack on record keeping. Making a point of paying for things with a check, card, or electronic payment method is a good way to make sure you have at least some documentation of your expenses. There are types of expenses that you need to be able to provide receipts for, mainly related to travel and meals .