diff --git a/apps/api/test/fleet.test.ts b/apps/api/test/fleet.test.ts
index 79af3494..c83667cb 100644
--- a/apps/api/test/fleet.test.ts
+++ b/apps/api/test/fleet.test.ts
@@ -57,6 +57,7 @@ function createBox(headers: Record<string, string>, body: object) {
 }
 
 afterAll(async () => {
+	await sql`delete from burn_segment where session_id in (select s.id from session s join box b on b.id = s.box_id where b.user_id = any(${createdUserIds}))`;
 	await sql`delete from session where box_id in (select id from box where user_id = any(${createdUserIds}))`;
 	await sql`delete from box where user_id = any(${createdUserIds})`;
 	await sql`delete from game where id = any(${createdGameIds})`;
@@ -167,3 +168,41 @@ describe('Entitlement on a fleet machine', () => {
 		expect((await may(p.owner.userId)).entitled).toBe(false);
 	});
 });
+
+describe('Billing a run on the fleet', () => {
+	test('a live fleet run accrues against the box owner’s personal team', async () => {
+		const f = await fleet(1);
+		useFleet(f.organisationId);
+		const machineId = f.machines[0]!.id;
+		const p = await person('bill-fleet');
+		const box = ((await (await createBox(p.headers, { on: 'fleet' })).json()) as any).data;
+
+		const [game] = await Game.upsert({
+			id: Identifier.ascending('game'),
+			steamAppId: 990002,
+			slug: 'fleet-bill',
+			name: 'Fleet Bill'
+		});
+		createdGameIds.push(game!.id);
+		const run = await Session.request({
+			id: Identifier.ascending('session'),
+			boxId: box.id,
+			gameId: game!.id,
+			linkedAccountId: p.owner.linkedAccountId
+		});
+		const claimToken = 'fleet-bill-claim-token-0001';
+		for (const state of ['starting', 'live'] as const) {
+			const r = await Session.transition({ id: run.id, machineId, state, claimToken });
+			expect(r.outcome).toBe('moved');
+		}
+
+		const open = await sql`select team_id, ended_at from burn_segment where session_id = ${run.id}`;
+		expect(open.length).toBe(1);
+		expect(open[0]!.team_id).toBe(p.owner.teamId);
+		expect(open[0]!.ended_at).toBeNull();
+
+		await Session.transition({ id: run.id, machineId, state: 'ended', claimToken });
+		const closed = await sql`select ended_at from burn_segment where session_id = ${run.id}`;
+		expect(closed[0]!.ended_at).not.toBeNull();
+	});
+});
diff --git a/packages/core/src/billing/index.ts b/packages/core/src/billing/index.ts
index ea4fda70..3076da59 100644
--- a/packages/core/src/billing/index.ts
+++ b/packages/core/src/billing/index.ts
@@ -46,10 +46,11 @@ export namespace Billing {
 	/**
 	 * The team that pays for a box.
 	 *
-	 * A box runs on a host, and the host says who owns it. Fleet hardware
-	 * belongs to an organisation, which is not a billing subject — nothing is
-	 * placed there yet, and when it is, what grants it is a plan rather than
-	 * this lookup.
+	 * On a person's own hardware, the team the host is registered under. On
+	 * the fleet, the hardware belongs to an organisation, which is not a
+	 * billing subject — so the run is the box owner's, and is billed to their
+	 * personal team, the one every account has and the one a plan is bought
+	 * on.
 	 */
 	export const teamForBox = fn(z.string(), async (boxId) => {
 		const box = await Box.fromID(boxId);
@@ -57,11 +58,14 @@ export namespace Billing {
 			return null;
 		}
 		const machine = await Machine.fromID(box.machineId);
-		if (!machine?.teamId) {
+		const teamId =
+			machine?.teamId ??
+			(machine?.organisationId ? ((await Team.personalFor(box.userId))?.id ?? null) : null);
+		if (!machine || !teamId) {
 			return null;
 		}
 		return {
-			teamId: machine.teamId,
+			teamId,
 			tier: box.tier as Burn.Tier,
 			// Whose hardware decides the cost basis, and the machine is the only
 			// thing that knows. A host an organisation owns is ours to pay for;
diff --git a/packages/core/src/session/index.ts b/packages/core/src/session/index.ts
index a65a3135..9c5987b9 100644
--- a/packages/core/src/session/index.ts
+++ b/packages/core/src/session/index.ts
@@ -2,6 +2,7 @@ import { and, desc, eq, inArray, isNull, sql } from 'drizzle-orm';
 import z from 'zod';
 
 import { Burn } from '../billing/burn.js';
+import { Billing } from '../billing/index.js';
 import { BoxTable, BoxTier } from '../box/box.sql.js';
 import { Box } from '../box/index.js';
 import { Database } from '../db/index.js';
@@ -9,7 +10,6 @@ import { ErrorCodes, VisibleError } from '../error.js';
 import { Examples } from '../examples.js';
 import { fn } from '../fn.js';
 import { GameTable } from '../game/game.sql.js';
-import { Machine } from '../machine/index.js';
 import { SessionState, SessionTable } from './session.sql.js';
 
 /**
@@ -661,25 +661,27 @@ export namespace Session {
 				// `live` is where it starts rather than `starting`, because what
 				// is billed is an envelope actually held — a box that never
 				// finished coming up held nothing.
-				const machine = await Machine.fromID(input.machineId);
-				if (machine?.teamId) {
+				// Who pays is `Billing.teamForBox`'s answer and nobody else's: the
+				// host's team on someone's own hardware, the box owner's personal
+				// team on the fleet.
+				const payer = await Billing.teamForBox(moved.boxId);
+				if (payer) {
 					if (current.state !== 'live' && moved.state === 'live') {
 						// The rate is fixed here, from what this run actually is:
 						// the size it holds, and whose card it holds it on. Both
 						// are settled before the run starts, which is what lets a
 						// person be told the cost before committing to it.
-						const box = await Box.fromID(moved.boxId);
 						await Burn.start({
-							teamId: machine.teamId,
+							teamId: payer.teamId,
 							sessionId: moved.id,
-							tier: (box?.tier ?? 'sm') as Burn.Tier,
-							hostClass: machine.organisationId ? 'fleet' : 'byo'
+							tier: payer.tier,
+							hostClass: payer.hostClass
 						});
 					} else if (
 						ACCRUING.includes(current.state as (typeof ACCRUING)[number]) &&
 						!ACCRUING.includes(moved.state as (typeof ACCRUING)[number])
 					) {
-						await Burn.stop({ teamId: machine.teamId, sessionId: moved.id });
+						await Burn.stop({ teamId: payer.teamId, sessionId: moved.id });
 					}
 				}