Birthday dinner for 12

A full itemized restaurant split, worked example: 12 people, one birthday, a mid-priced neighborhood restaurant, and one payer who covers the whole check.

The setup

Twelve people, one of them (Maya) turning thirty. Reservation at a neighborhood restaurant with an average entree around $24. One person (Ben) puts the whole check on his card because the restaurant won't split more than two ways. The group agrees: Maya doesn't pay, her share gets split among the other eleven.

The itemized subtotal

After food and drinks, the pre-tax subtotal breaks down as:

  • Maya (guest of honor): entree $28, cocktail $14, dessert $9 → $51
  • Ben (payer): entree $26, cocktail $13, appetizer share $6 → $45
  • Chris: entree $22, beer $8, appetizer share $6 → $36
  • Dana: entree $24, wine $12, appetizer share $6 → $42
  • Elle: entree $28, water, appetizer share $6 → $34
  • Fatima: salad $16, no drink → $16
  • Greg: entree $24, two beers $16 → $40
  • Hannah: entree $22, cocktail $14 → $36
  • Ivan: entree $26, wine $12, dessert $9 → $47
  • Jules: entree $22, cocktail $14 → $36
  • Kai: entree $24, beer $8 → $32
  • Lena: salmon $30, cocktail $14 → $44

Subtotal: $459.

Tax, tip, and fees

  • Sales tax at 8%: $459 × 0.08 = $36.72
  • Tip at 22% on pre-tax subtotal: $459 × 0.22 = $100.98
  • No service fees

Extras total: $137.70. Final bill: $596.70.

Splitting Maya's share among the other eleven

Maya's subtotal is $51. Her share of the extras is (51 / 459) × $137.70 = $15.30. Maya's full total would have been $51 + $15.30 = $66.30.

The other eleven split Maya's $66.30 evenly: $66.30 ÷ 11 = $6.03 added to each of their proportional totals.

Everyone's final number

Each person's proportional share of the total bill (their subtotal ÷ $459, times $596.70), plus $6.03 for covering Maya's share. Rounded to the nearest cent:

  • Ben (payer): $58.50 + $6.03 = $64.53
  • Chris: $46.80 + $6.03 = $52.83
  • Dana: $54.60 + $6.03 = $60.63
  • Elle: $44.20 + $6.03 = $50.23
  • Fatima: $20.80 + $6.03 = $26.83
  • Greg: $52.00 + $6.03 = $58.03
  • Hannah: $46.80 + $6.03 = $52.83
  • Ivan: $61.10 + $6.03 = $67.13
  • Jules: $46.80 + $6.03 = $52.83
  • Kai: $41.60 + $6.03 = $47.63
  • Lena: $57.20 + $6.03 = $63.23
  • Maya: $0

Check: $64.53 + $52.83 + $60.63 + $50.23 + $26.83 + $58.03 + $52.83 + $67.13 + $52.83 + $47.63 + $63.23 = $596.73 (three cents of rounding, absorbed by the payer).

What made this work

Three things kept this simple:

  • Everyone knew before ordering that Maya wasn't paying and her share would be covered.
  • Ben used proportional tax and tip (not even splits), so Fatima's $16 salad didn't cost her $50.
  • Ben sent each person a specific number the same night, before anyone had time to forget what they ordered.

For a bill this size, doing the math by hand is a chore. Use BillSplitterApp to enter the items once, let each friend claim their own, and get every number automatically — including the guest-of-honor cover math.