How to split a restaurant bill with tax and tip

1. Start with the itemized receipt

Take a photo or upload a receipt, then check the extracted items and amounts. A line's cost is its unit price multiplied by its quantity. Two teas at $3 each should total $6. Correct scan errors and compare the calculated bill total with the receipt before sharing.

Check whether a gratuity is already included so you do not accidentally add it twice. Keep mandatory fees separate from the food and drinks.

2. Assign individual items and shared dishes

Each person selects what they had. Equal portions divide a dish evenly among its claimants. Portions of 2 and 1 divide a $24 pizza into $16 and $8. They are relative weights, not a fixed fraction: if a third person claims 1 portion, the split becomes $12, $6 and $6.

To share the whole bill evenly, give everyone equal portions of every food and drink item. Their item subtotals, tax and tip will then match apart from cent-rounding differences. There is no separate equal-bill button.

You can do the whole split on one device. As organizer, use Add in the People row, select each person, then assign their items and portions. Hold a name on a phone or double-click it on desktop to rename it. In the summary, choose Finalize tab, or expand a person's breakdown to review their items separately.

Live splitting is optional. Share an invitation link or QR code if friends want to pick their own items in their browsers. Changes update across connected devices. Someone you already added can choose their existing name when joining.

3. Divide tax, tip and service charges

The item subtotal includes food and drinks, before service charges, tax and tip. ShareTheTab divides the tax amount entered for the bill; it does not calculate local tax rates or separate taxable and tax-exempt items.

• Tax and tip always follow each person's item subtotal. There is no equal or custom per-person allocation setting for either.
• Service charges default to proportional. In receipt review, choose % of food or Equal. The choice applies to all service charges together.
• Equal service charges divide the fee among everyone added to the split, including people with no selected items. An expected guest counts only once added by the organizer or joined through the invitation.

Your tax share = total tax × your item subtotal ÷ the full food and drink subtotal.

The same formula applies to tip and proportional service charges. For example, 40% of the item subtotal means 40% of each charge, before cent rounding. With a zero item subtotal, proportional shares are zero.

Choose the total tip

Enter the total tip amount during receipt review. If the tip is missing later, choose Add tip for 15%, 18%, 20% and 25% presets or a custom amount. Choose No tip on the item-selection screen if none is needed. Presets use the food and drink subtotal, excluding tax and service charges. On a $30 subtotal, 20% adds $6.

To tip on a different base, calculate that amount and enter it as a custom total. Either way, the app divides the resulting tip proportionally. It does not assign a different tip rate to each person.

How rounding works

Each item's shares are allocated in cents first. Those amounts make up each person's subtotal, which is then used to divide the fees. Fractional cents are rounded down, and remaining cents go to the largest fractional remainders. Equal remainders keep their existing order.

A $10 dish shared equally three ways becomes $3.34, $3.33 and $3.33. Tax, tip and service charges are allocated separately, then added to each person's items. This avoids losing a cent by rounding every share independently.

Example: a shared pizza, two drinks and a $41.40 bill

Alice eats two thirds of a $24 pizza; Bob eats one third and has two $3 teas. Their item subtotal is $30. The receipt also has a $3 service charge, $2.40 tax and $6 tip. With proportional service charges, the bill splits like this:

Alice's tax is $2.40 × $16 ÷ $30 = $1.28. Bob's is $1.12. With equal service charges, each pays $1.50 for service. Alice then owes $21.98 and Bob $19.42, still totaling $41.40. Tax and tip do not change.

4. Confirm everyone’s items before settling up

Totals stay pending until everyone expected has been added or joined, every food and drink item is claimed, and each person's selections are confirmed. The organizer's Finalize tab button skips individual reviews once the full bill is allocated. Missing people and unclaimed items must still be resolved.

Check the final breakdown and total tip together, then pay outside the app. Confirmation does not lock the bill permanently. Reopening selections or editing the receipt can change the totals.