diff --git a/CHANGES.md b/CHANGES.md
index 9c38282..6455edb 100644
--- a/CHANGES.md
+++ b/CHANGES.md
@@ -1,6 +1,7 @@
 # Changes
 
 ## Unreleased
+- Add splitBill(items, people) to split the taxed total into per-person shares.
 
 ## 1.2.0
 - total() rounds through roundCents().
diff --git a/src/lib/cart.js b/src/lib/cart.js
index 385fd69..903adb9 100644
--- a/src/lib/cart.js
+++ b/src/lib/cart.js
@@ -8,3 +8,15 @@ export function subtotal(items) {
 export function total(items) {
   return roundCents(subtotal(items) * (1 + TAX_RATE));
 }
+
+// Splits the taxed total between `people` (a count). Works in whole cents so the
+// shares always add up to total(); leftover cents go to the first people.
+export function splitBill(items, people) {
+  if (!Number.isInteger(people) || people < 1) {
+    throw new RangeError('people must be a positive integer');
+  }
+  const cents = roundCents(total(items) * 100);
+  const extra = cents % people;
+  const base = (cents - extra) / people;
+  return Array.from({ length: people }, (_, i) => (base + (i < extra ? 1 : 0)) / 100);
+}
diff --git a/tests/lib/cart.test.js b/tests/lib/cart.test.js
index 7a9eab3..901cf2b 100644
--- a/tests/lib/cart.test.js
+++ b/tests/lib/cart.test.js
@@ -1,6 +1,6 @@
 import { test } from 'node:test';
 import assert from 'node:assert/strict';
-import { subtotal, total } from '../../src/lib/cart.js';
+import { subtotal, total, splitBill } from '../../src/lib/cart.js';
 
 const items = [{ price: 10, qty: 2 }, { price: 5, qty: 1 }];
 
@@ -11,3 +11,26 @@ test('subtotal adds price times quantity', () => {
 test('total applies tax and rounds to cents', () => {
   assert.equal(total(items), 27);
 });
+
+test('splitBill splits the taxed total evenly', () => {
+  assert.deepEqual(splitBill(items, 2), [13.5, 13.5]);
+});
+
+test('splitBill shares always sum to the total, extra cents go to the first people', () => {
+  const shares = splitBill(items, 4); // 27.00 / 4
+  assert.deepEqual(shares, [6.75, 6.75, 6.75, 6.75]);
+  const uneven = splitBill(items, 7); // 2700 cents / 7
+  assert.equal(uneven.length, 7);
+  assert.deepEqual(uneven.slice(0, 5), [3.86, 3.86, 3.86, 3.86, 3.86]);
+  assert.deepEqual(uneven.slice(5), [3.85, 3.85]);
+  assert.equal(Math.round(uneven.reduce((a, b) => a + b, 0) * 100), 2700);
+});
+
+test('splitBill with one person returns the whole total', () => {
+  assert.deepEqual(splitBill(items, 1), [27]);
+});
+
+test('splitBill rejects an invalid number of people', () => {
+  assert.throws(() => splitBill(items, 0), RangeError);
+  assert.throws(() => splitBill(items, 1.5), RangeError);
+});