How to split a grocery receipt with roommates, to the cent

Three people, one card, one receipt. Dividing the total by three is quick, and it is fair only when everyone eats roughly the same things. Once one roommate buys protein bars and another buys shampoo, an even split quietly moves money from one person to another. The fix takes about five minutes a receipt: tag every line, split the shared lines, share the coupon and the tax in proportion, and settle up once a month.

01Pick how strict you want to be

There are three common ways to split groceries. None is wrong. They trade effort for precision.

This guide uses line by line, because it is the only method that gives an exact answer on a mixed receipt. If your apartment runs an even split, the settle-up section still applies.

02Decide what counts as shared

Agree on the rules once, not at every receipt. A short list covers almost everything:

• Shared: staples everyone uses (milk, eggs, bread, oil, spices) and anything that keeps the apartment running (toilet paper, dish soap, hand soap, trash bags).
• Personal: anything one person asked for, eats alone, or would be annoyed to find finished.
• Special diets are personal. If one of you drinks oat milk and the others drink dairy, the oat milk is personal and the dairy is shared, even though both are milk.
• A saving printed under one item, such as a member price, belongs to whoever owns that item.

Pin the rules in the group chat so nobody has to remember them. If the abbreviations on your receipts make lines hard to identify, how to read a grocery receipt walks through the codes.

03The example receipt

Maya, Jonah and Priya share an apartment. Maya paid for this week's shop. Lines marked T were taxed and the rest were not, and a store coupon came off the whole bill.

Tag every line. Shared lines are split three ways, and the rest go to one person.

• Shared, $44.61: whole milk, eggs, sourdough, bananas, olive oil, toilet paper and hand soap.
• Maya, $13.37: oat milk and Greek yogurt.
• Jonah, $23.97: protein bars and frozen pizza.
• Priya, $16.48: ground coffee and shampoo.

Check the tags before going further: 44.61 + 13.37 + 23.97 + 16.48 = 98.43, the subtotal. If your tagged amounts don't reach the subtotal, a line is missing or tagged twice.

04Split the coupon and the tax in proportion

Lines are easy because each one has an owner. The coupon and the tax don't. The fair rule is proportion: each person gets a share of the coupon equal to their share of the spending, and a share of the tax equal to their share of the taxed lines.

1. 1Add up each person's spending before the coupon: their own lines plus a third of the shared lines. The shared lines come to 44.61, which is 14.87 each. Maya: 13.37 + 14.87 = 28.24. Jonah: 38.84. Priya: 31.35.
2. 2Coupon: multiply the coupon by each person's spending and divide by the subtotal. Maya: 5.00 × 28.24 ÷ 98.43 = 1.43.
3. 3Tax: find each person's taxed amount first. The shared taxed lines (toilet paper and hand soap) come to 15.48, or 5.16 each. Priya adds her shampoo for 12.15. Then multiply the tax by each taxed amount and divide by all taxed lines. Priya: 1.80 × 12.15 ÷ 22.47 = 0.97.
4. 4Round each share to the cent and add up the column. If it comes out a cent short or over, the person with the biggest share in that column takes the difference. Agree on that rule once and nobody argues over a penny.

Spreading the tax over the whole bill is simpler, and less fair. On this receipt only three lines were taxed, and one of them was Priya's shampoo. Spreading the tax over all spending would charge Jonah 0.71 in tax instead of 0.41, partly for Priya's shampoo. It is cents here and dollars on a big household shop.

05The split, to the cent

Jonah's coupon share works out to 1.973 and Priya's tax share to 0.973. Rounded down, each column is a cent short, so each extra cent goes to the biggest share in its column: Jonah's coupon becomes 1.98 and Priya's tax 0.98. Now the three amounts add up to exactly $95.23, the receipt total.

For comparison, an even split is $31.74 each, with one person paying $31.75. Maya would pay $4.52 more than her share, Priya about $1 more, and Jonah $5.53 less. If every week looked like this one, Maya and Priya would put about $288 a year toward Jonah's shopping.

06Settle up once a month

Paying each other back after every shop means dozens of tiny transfers. Keep a running tab instead. After each shop, whoever paid writes down the date, the total and each person's share. At the end of the month, each person's balance is what they paid at the till minus what they owed.

A positive balance means the others owe you, and a negative one means you owe. The balances always add up to zero (34.36 − 3.47 − 30.89 = 0), which is your check that nothing was mistyped. Here two transfers close the month: Jonah sends Maya $3.47 and Priya sends Maya $30.89. Three people never need more than two transfers, however many shops there were.

Keep the receipts, or photos of them, until the month is settled. If someone questions a share, the paper settles it faster than anyone's memory. Settling up fits well into a monthly money review, since you are already looking at the month's receipts.

07Where Sorayli fits, and where it doesn't

The Sorayli app has no bill-splitting feature, only the free split tool on this site. There is no shared ledger, no roommate balance and no settle-up screen, and it won't work out who owes whom. Each account is one person's own ledger. Keep the tab in a shared spreadsheet or a bill-splitting app alongside it.

What it does is the tedious first step. Scan the receipt and Sorayli reads each line with its quantity and price and suggests a category for each, like the Food & Dining and Personal Care tags above. You tag shared and personal from a clean list instead of faded thermal paper, and the photo stays with your account in case anyone asks to see it.

It also keeps your own spending accurate. On the review screen, on the web or the iPhone app, you can edit, remove or add lines before saving, and when a receipt has more than one line, each line is saved as its own transaction. As the payer, Maya can remove Jonah's and Priya's personal lines, keep her own two, and replace the shared lines with one line for the rest of her share: 27.22 − 13.37 = 13.85, named something like "Shared groceries, my share". Her ledger then shows $27.22 of groceries, which is what she really spent, so a grocery budget measures the right number. The trade-off is that her ledger won't match the $95.23 card charge, so the receipt photo is her record of the full bill.

• On the iPhone app, the review screen takes one note for the whole receipt, such as "Split three ways, Maya paid", and copies it onto every line.
• On the web, the Transactions page searches by name, filters by date (this month, last month or a custom range), and shows the total of what is listed. Name your share lines the same way each time and a month of them is one search.
• Sorayli reads the tax to check the receipt's arithmetic, but doesn't show it or add it to your lines. On a receipt with tax added at the bottom, like this one, the lines are usually recorded at their printed prices, before the coupon. Do the split itself from the paper or the photo, as above.
• Roommates who didn't pay can type their share in by hand. Typing is unlimited on every plan, and the Free plan includes 10 scans a month, enough for a weekly shop. Compare plans if you need more.