The methods
Five ordinary ways to keep grocery receipts. They answer different questions, and the useful thing is knowing which question you have.
Paper in a folder or envelope
Organizes by trip. Good at keeping the original purchase document, which is what a return or a dispute may ask for. Costs nothing and needs no setup.
Hard later: anything about a product. Finding what you paid for one item last spring means reading through the receipts one at a time.
If the only reason you keep receipts is an occasional return, this is enough.
Photos or scans in a folder
Organizes by file, usually by date. Good at keeping a copy without keeping the paper, and reachable from anywhere.
Hard later: a folder of images organizes documents. Text recognition can make the words inside them searchable, which helps if you remember how the store printed the item. You still get back a receipt to read rather than an answer.
Reasonable to stop here if you want a copy of the paper and nothing more.
Emailed receipts and retailer accounts
Organizes by retailer. Good at being automatic. You buy something and the record appears.
Hard later: it covers that retailer only, and what each one keeps, how much detail it shows and how long it stays available varies. Shop at three places and your shopping sits in three separate systems.
A spreadsheet you keep yourself
Organizes by whatever you decide, which is the point of it. You choose what to record and how to structure it, and you can enter purchases that never produced a receipt.
Hard later: it asks you to type, consistently, for as long as you keep it up. We publish a free template and an honest account of that cost: a grocery spending template and the rules that keep it accurate.
Itemized purchase records
Organizes by what was bought rather than by the trip it was bought on. The receipt is read once, each line becomes a record, and the document stops being the only way in.
Hard later: it depends on there being something itemized to read. A purchase with no itemized record, like a delivery with no breakdown, leaves nothing reliable to extract. Faint print reads badly. Where the evidence doesn’t establish a detail, it’s left blank rather than filled in with something plausible.
This is what CartEncore does. It isn’t the right answer for someone who wants a copy of the paper and nothing else.