How to scan receipts with your phone properly

Flatten the receipt, put it on a surface that contrasts with the paper, hold the phone parallel to it rather than at an angle, fill the frame with the slip, and use ambient light instead of the flash. That is most of it. The photo is the only part of receipt scanning you fully control, and it determines the ceiling on everything the software can do afterwards.

Detail that isn’t in the image cannot be recovered later. So the whole of capture technique is about getting the printed characters into the file legibly, once.

Flat beats everything

A receipt that has been rolled or folded has a curved printing baseline. Software can correct mild curvature; a tight curl bends characters into shapes that recognition genuinely cannot resolve.

Flattening takes two seconds. Press it under a hand, run it over a table edge to reverse the curl, or put something heavy on it while you line up the shot. If a slip is stubbornly rolled, fold it flat rather than photographing the curl — a crease that doesn’t cross the total costs you far less than curvature does.

Contrast the background

Edge detection is what lets the software find the receipt and correct its perspective. It needs to be able to tell paper from not-paper.

A white receipt on a white table is the classic failure: the crop either grabs the whole table or cuts a corner off the slip. Put white paper on something dark. Dark surfaces work for essentially every receipt, which makes “one dark placemat where receipts get photographed” a genuinely effective piece of setup.

Shoot parallel, not at an angle

Hold the phone flat above the receipt, its plane parallel to the paper. Perspective correction exists and works, but it works by stretching pixels — the far end of a steeply angled receipt has fewer pixels per character, and stretching invents no new detail. Small text at the far end is where the losses land.

Directly overhead, and centred, means uniform resolution across the whole slip.

Fill the frame

The slip should occupy most of the image. A receipt photographed as a small object in the middle of a large room is a low-resolution receipt no matter how many megapixels the sensor has, because only a fraction of them are pointed at the paper.

Get close enough that the receipt nearly touches the frame edges, leaving a small margin so edge detection has something to work with. If your camera won’t focus that close, back off slightly rather than shooting out of focus — blur costs more than framing.

Light it evenly, and avoid the flash

Thermal receipt paper has a glossy coating. A direct flash reflects off it, and the reflection lands as a blown-out white patch — which, given where people hold phones, tends to sit right over the middle of the slip.

Ambient light, near a window or under room lighting, is almost always better. What you’re avoiding is any single bright source reflecting straight back at the lens. If the room is dim, move to a brighter one; if you must use light from one side, watch for your own hand or phone casting a shadow across the paper.

Check the shot before you bin the paper

The single habit that prevents the most rework: glance at the photo, confirm the total and date are legible to you, and only then throw the receipt away.

If you can’t read the total in the image, no software will. Two seconds of checking beats discovering the problem weeks later when the paper is gone.

Awkward cases

Very long receipts. A supermarket slip longer than the frame is a real problem. If you only need the total and date, photograph the bottom portion where both appear. If you need line items, take two overlapping photos rather than one distant photo of the whole thing — resolution matters more than having it in one file.

Faded receipts. Once thermal print has gone grey, capture technique can only do so much. Strong even light and high contrast help marginally. The real fix is upstream: photograph thermal receipts the day you get them, because fading is progressive and irreversible.

Crumpled receipts. Flatten as best you can, and prioritise the region containing the total. A crease across a number is worse than a crease anywhere else, so orient your flattening effort accordingly.

Emailed receipts. Don’t photograph a screen. Screen photos add moiré patterns, glare and pixel-grid artefacts to text that was perfectly clean as a file. Save the PDF or forward the email instead.

The two-thing version

If you only remember two things: flatten it and shoot straight down onto a contrasting surface. Those two habits fix the majority of capture failures, and everything else on this page is a refinement of them.