How to Split a Restaurant Bill and Calculate Tip

A dinner for six ends with a single bill and five phones out. The check shows a $120.00 subtotal, 8% sales tax, and no tip line item filled in — the server is waiting. What each person owes is not one calculation but three: the tip, the tax, and the split itself. Getting the order of those calculations right matters, because the wrong order changes the answer, and a split that is off by even a few dollars is the kind of thing a table remembers.

This guide works through the exact formulas, a complete example for an evenly split dinner, the proportional method for tables where one person ordered the lobster and another ordered the salad, and the cent-reconciliation problem that catches almost every manual split. It also covers the tipping conventions that decide which numbers go into the formulas: pre-tax versus post-tax tipping, and how service charges interact with the tip.

The three formulas, in order

The bill has a natural order of operations: tip and tax are both calculated from the pre-tax subtotal, the grand total is the sum of all three parts, and the split is applied to the grand total last.

1. Tip = subtotal × tip rate ÷ 100. The tip is calculated on the pre-tax subtotal, not on the amount after tax. The reason is a matter of convention, not arithmetic: the tip rewards the service, and tax is not part of the service. Most etiquette guides in the United States state 18–20% of the pre-tax bill as the standard for sit-down table service, with 15% on the low end and 25% for exceptional service.

2. Tax = subtotal × tax rate ÷ 100. The tax rate is printed on the receipt in US states, or worked backwards from the bill in countries where prices include tax.

3. Total = subtotal + tip + tax. Then: per person = total ÷ number of people.

The order matters because the tip base must be the subtotal alone. Tipping on the taxed total is not wrong — it is simply slightly more generous. On a $100 subtotal with 8% tax, a 20% tip on the pre-tax amount is $20.00, while 20% on the taxed amount ($108) is $21.60 — a difference of $1.60. If the table has agreed on 20% pre-tax and someone applies it post-tax, the collected total will be a few dollars short or long, and nobody will know whose arithmetic was off.

The tip calculator on this site applies the same formulas: tip on the pre-tax amount, tax added separately, and an even split across the headcount.

Worked example: a $120 dinner split six ways

Six friends share a dinner. The receipt shows:

• Subtotal: $120.00
• Sales tax: 8%
• Tip: 18% on the pre-tax subtotal
• People splitting: 6

Step 1 — Tax. $120.00 × 8 ÷ 100 = $9.60. The tax is always computed on the subtotal.

Step 2 — Tip. $120.00 × 18 ÷ 100 = $21.60. Note that the 18% applies to $120.00, not to $129.60 (the subtotal plus tax). If the tip were applied to $129.60, it would come to $23.33 — an extra $1.73 that the table did not agree to pay.

Step 3 — Grand total. $120.00 + $9.60 + $21.60 = $151.20.

Step 4 — Split. $151.20 ÷ 6 = $25.20 per person.

The check that confirms the arithmetic: 6 × $25.20 = $151.20, which matches the grand total exactly. When every share is identical, the multiplication check always closes cleanly.

A useful shortcut for estimating at the table: 10% of the subtotal is a decimal shift ($12.00 here), so 20% is twice that ($24.00) and 15% is 10% plus half of 10% ($12.00 + $6.00 = $18.00). These estimates land within a dollar or two of the exact tip for most bills, and they are fast enough to settle the tip question before the server returns.

The tip rate to use

The right percentage depends on the service and the country. The most commonly cited US bands are:

These are conventions, not laws, and they vary by country: in Japan and South Korea tipping is not customary and can be refused, while in many European countries a small rounding-up or 5–10% is sufficient because service is typically included in menu prices. When travelling, the local custom outranks any formula.

The percentage calculator is handy for any off-standard rate: a 22% tip on a $120 bill is $120 × 0.22 = $26.40.

Uneven orders: the proportional split

An even split is the simplest fair answer when everyone ordered roughly the same. When one person ordered a $48 steak and another ordered a $22 salad, an even split overcharges the salad and undercharges the steak. The fair method is proportional: each person pays their own subtotal, plus their share of the tax and tip in proportion to what they ordered.

Work it through with two diners, A and B:

• A ordered $48.00 of food; B ordered $22.00. Combined subtotal: $70.00.
• Tax at 8%: $70.00 × 0.08 = $5.60.
• Tip at 18% pre-tax: $70.00 × 0.18 = $12.60.
• Grand total: $70.00 + $5.60 + $12.60 = $88.20.

Each person’s share of the tax and tip is proportional to their share of the subtotal:

Diner A’s share of the subtotal: $48.00 ÷ $70.00 = 0.6857 (68.57%).
– A’s tax: $5.60 × 0.6857 = $3.84
– A’s tip: $12.60 × 0.6857 = $8.64
– A’s total: $48.00 + $3.84 + $8.64 = $60.48

Diner B’s share of the subtotal: $22.00 ÷ $70.00 = 0.3143 (31.43%).
– B’s tax: $5.60 × 0.3143 = $1.76
– B’s tip: $12.60 × 0.3143 = $3.96
– B’s total: $22.00 + $1.76 + $3.96 = $27.72

The reconciliation check: $60.48 + $27.72 = $88.20, exactly the grand total. The method works for any headcount — each person is taxed and tipped in proportion to their own ordering — and it is the only split method where the person who ordered the steak pays the steak’s tax and the steak’s tip.

A simpler shortcut the table sometimes uses is to split the tax and tip evenly while itemizing only the food: each person pays their own food plus an equal share of tax + tip. On the example above, that would give A $48.00 + $9.10 = $57.10 and B $22.00 + $9.10 = $31.10. It is quicker, but it is not fully fair: the tax and tip on the steak should not be shared with the person who ate the salad. For a table of friends who want speed over precision, the shortcut is acceptable; for a work dinner or a group where orders differ wildly, use the proportional method.

The missing-cent problem

Here is the calculation error that catches nearly every manual split. A grand total of $101.95 split four ways:

$101.95 ÷ 4 = $25.4875, which rounds to $25.49 per person. But 4 × $25.49 = $101.96 — one cent more than the bill.

The reverse problem is more common: a $100.00 total split three ways gives $33.33 per person after rounding, and 3 × $33.33 = $99.99 — one cent less than the bill. Someone always covers the missing cent without noticing, or the group discovers the shortfall at the register.

The correct fix is the largest-remainder method, worked in whole cents rather than decimal dollars:

1. Convert the total to cents: $101.95 = 10,195 cents.
2. Divide by the headcount: 10,195 ÷ 4 = 2,548 remainder 3.
3. Give each person 2,548 cents ($25.48), then distribute the 3 leftover cents one at a time to the first three people.

The result: three people pay $25.49 and one pays $25.48. The shares sum to exactly $101.95. Who gets the extra cents is arbitrary — rotate the order or let the person who ordered the most expensive item take the first one.

Whenever the per-person amounts do not multiply back to the exact total, the split is wrong, and the fix is always to work in cents with the remainder distributed one cent at a time. No manual split should ever end with “we’re a few cents short, I’ll cover it.”

Pre-tax versus post-tax tipping: the detail that shifts the total

The convention in the United States is to tip on the pre-tax subtotal. The reasoning is straightforward: the tip is a gratuity for the service, and the tax is a government levy that the server did not provide. Tipping on the taxed amount effectively tips the tax collector, and over a year of dinners, the difference adds up: on a weekly $100 dinner with 8% tax, tipping 20% post-tax instead of pre-tax costs an extra $1.60 a week, or about $83 a year.

Some POS terminals, however, default to suggesting tip percentages on the post-tax total, and many diners tip on whatever the screen suggests. Neither choice is a breach of etiquette — post-tax tipping is simply more generous. What matters for the split is consistency: the whole table must use the same base. A table where three people tipped on $120 and three tipped on $129.60 will collect an amount that matches nobody’s calculation, and the reconciliation will fail for no visible reason.

In countries where prices include tax (most of Europe, Australia, Japan), the distinction does not arise: the bill is the bill, and the tip is calculated on it directly.

Service charges, autograt, and double tipping

Before calculating a tip, check the receipt for a service charge or automatic gratuity. Many US restaurants add an automatic gratuity of 18–20% for parties of six or more; it is printed on the receipt as “service charge” or “autograt.” That charge IS the tip — adding a further 18–20% on top of it is double tipping.

The rule for the split: if a service charge is present, tip = the service charge (adjust up only if the service genuinely warranted more, and note that some states treat a mandatory service charge as restaurant revenue, not as a gratuity to the server). If there is no service charge, calculate the tip with the formula above. Reading the receipt before doing any math is the single highest-value step in the whole process.

Rounding up for cash

When the table pays in cash, exact cents are impractical. The common approach is to round each person’s share up to the next whole dollar. On the six-person example, $25.20 per person rounds to $26.00 — an extra $0.80 per person, or $4.80 over the bill. The server keeps the excess, which is the point: rounding up guarantees the tip is never shorted by the rounding.

The rounding should be disclosed before it happens: “everyone round your $25.20 up to $26 and the server gets the extra” is transparent; silent over-collection is how a $151.20 bill becomes $160 in the envelope with no one able to say why. If the extra amount feels large, round up only to the nearest dollar on the total, not per person.

A quick-reference checklist for the table

1. Read the receipt for a service charge before doing any math.
2. Agree the tip rate (18–20% pre-tax is the US default) before calculating.
3. Tip on the pre-tax subtotal, not the taxed total — unless the table agrees otherwise.
4. Calculate tax and tip, then sum for the grand total.
5. Split evenly when orders are similar; split proportionally when they differ.
6. Reconcile in cents: multiply each share back and confirm the sum equals the total; distribute leftover cents one at a time.
7. Round up openly for cash, and say so before collecting.

The sales tax calculator handles step 4’s tax portion for any state rate, and the discount off calculator is the companion calculation when a coupon or restaurant promo reduces the subtotal before the tip — note that etiquette generally says to tip on the pre-discount subtotal, since the server served the full meal.

Frequently asked questions

How do you calculate a tip on a restaurant bill?

Multiply the pre-tax subtotal by the tip rate and divide by 100: tip = subtotal × rate ÷ 100. On a $120 subtotal at 18%, the tip is $120 × 0.18 = $21.60. Then add the tip and the tax to the subtotal for the grand total. The US convention is to tip on the pre-tax amount, not on the taxed total.

How do you split a restaurant bill evenly?

Add the subtotal, the tip, and the tax together for the grand total, then divide by the number of people: per person = total ÷ people. For a $151.20 total across six people, each person pays $25.20. An even split is fair when everyone ordered similar-priced items.

How do you split a bill fairly when people ordered different things?

Use the proportional method. Each person pays their own food subtotal, plus their proportional share of the tax and tip: a person whose order is 68.57% of the combined subtotal pays 68.57% of the tax and 68.57% of the tip. In the worked example, the $48-order diner pays $60.48 total and the $22-order diner pays $27.72, and the two shares sum to the exact $88.20 grand total.

Should the tip be calculated before or after tax?

Before tax. The US convention is to tip on the pre-tax subtotal, because tax is not a service the restaurant provided. Tipping after tax is not wrong — it is just slightly more generous: on a $100 bill with 8% tax, a 20% tip is $20.00 pre-tax versus $21.60 post-tax. The critical thing is that everyone at the table uses the same base.

What is a good tip percentage at a restaurant in 2026?

For sit-down table service in the US, 18–20% of the pre-tax bill is the current standard, with 15% on the low end and 25% for exceptional service. These bands have crept upward over the decades — 15% was the standard in the 1990s — but they vary by country, and in some countries tipping is not customary at all.

How do you handle the cents when splitting a bill?

Work in whole cents and distribute the remainder one cent at a time. Convert the total to cents, divide by the headcount, give each person the floor of that division, then hand out the leftover cents one apiece starting from the first person. Three people on $100.00 pay $33.34, $33.33, and $33.33 — which sums to exactly $100.00.

What if the restaurant already added a service charge?

Then the tip is already included — do not add another full tip on top. A service charge or automatic gratuity (common for parties of six or more, usually 18–20%) is the gratuity. Check the receipt for it before calculating anything; double tipping is the most expensive arithmetic mistake at a restaurant.

Should you tip on the full price when you have a coupon or discount?

Yes — tip on the pre-discount subtotal. The server provided the full meal regardless of the promo, so tipping on the discounted amount short-changes them. If a $120 dinner is discounted to $96, the 18% tip should still be calculated on $120, i.e. $21.60, not $17.28.

How do you split a bill when someone leaves before it arrives?

The fair approach is to calculate that person’s share at the time they leave — their items, plus their proportional share of tax and the agreed tip — and collect it then. Waiting until the end of the meal and trying to reconstruct the order from memory is how disputes start. The proportional split method handles this cleanly: their subtotal is known, so their share is computable immediately.

Does an even split ever under-tip the server?

Yes, through a subtle path. An even split calculates the tip correctly on the full bill, so the server is fine. The under-tipping risk comes earlier: when each person “tips on their own portion” mentally and rounds down their own share. Six people each rounding $25.20 down to $25.00 removes $1.20 from the collected total — and that $1.20 comes out of the tip first. Always reconcile each share back to the exact total, and round up, never down.