diff --git a/src/main/runtime/owned-session-teardown-policy.test.ts b/src/main/runtime/owned-session-teardown-policy.test.ts
index fffbd4fa109..06bad768a44 100644
--- a/src/main/runtime/owned-session-teardown-policy.test.ts
+++ b/src/main/runtime/owned-session-teardown-policy.test.ts
@@ -1,8 +1,14 @@
+import { readdirSync, readFileSync } from 'node:fs'
+import { join } from 'node:path'
 import { describe, expect, it, vi } from 'vitest'
 import type { RuntimeClientEvent } from '../../shared/runtime-client-events'
 import type { RuntimeNotifier } from './runtime-notifier-contract'
 import type { AgentBrowserBridge } from '../browser/agent-browser-bridge'
-import { OWNED_SESSION_KINDS, OWNED_SESSION_TEARDOWN } from './owned-session-teardown-policy'
+import {
+  OWNED_SESSION_KINDS,
+  OWNED_SESSION_TEARDOWN,
+  type OwnedSessionKind
+} from './owned-session-teardown-policy'
 import {
   getRuntimeBrowserPageRegistry,
   type RuntimeBrowserClientPage
@@ -146,4 +152,77 @@ describe('owned-session teardown policy', () => {
       expect(release.mock.calls.map(([worktreeId]) => worktreeId)).toEqual(released)
     }
   )
+
+  it("stops every project workspace's terminals under one deadline, not one after another", async () => {
+    const { runtime, runtimeStore } = makeRuntime()
+    const [repo] = runtimeStore.getRepos()
+    const slow = `${repo.id}::/slow`
+    const fast = `${repo.id}::/fast`
+    // oxlint-disable-next-line typescript/consistent-type-assertions -- SAFETY: the sweep reads only id and repoId.
+    const worktrees = new Map([slow, fast].map((id) => [id, { id, repoId: repo.id }])) as never
+    vi.spyOn(runtime, 'getResolvedWorktreeMap').mockResolvedValue(worktrees)
+    const stop = vi.spyOn(runtime, 'stopTerminalsForWorktree').mockImplementation(
+      async (selector) =>
+        await new Promise<{ stopped: number }>((resolve) => {
+          // The slow workspace's provider never answers; the fast one takes a moment.
+          if (selector === `id:${fast}`) {
+            setTimeout(() => resolve({ stopped: 1 }), 20)
+          }
+        })
+    )
+
+    const result = await runtime.stopTerminalsForProject(repo, { deadline: Date.now() + 500 })
+
+    expect(stop.mock.calls.map(([selector]) => selector).sort()).toEqual([
+      `id:${fast}`,
+      `id:${slow}`
+    ])
+    expect(result.stopped).toBe(1)
+  })
+})
+
+// Every exported or method-level stop/close/teardown of a workspace's sessions in src/main/runtime,
+// and the owned-session kinds it ends. A new one fails here until someone classifies it.
+const TEARDOWN_FUNCTIONS: Readonly<Record<string, readonly OwnedSessionKind[]>> = {
+  closeClientHostedBrowserPagesForWorktree: ['host-browser'],
+  closeStructuredSessionsForProject: ['structured-chat'],
+  closeStructuredSessionsForWorktree: ['structured-chat'],
+  retireStructuredSessionTabsForWorktree: ['structured-chat'],
+  closeTerminalsForWorktree: ['pty'],
+  killAllProcessesForWorktree: ['pty', 'structured-chat'],
+  sleepTerminalsForWorktree: ['pty'],
+  stopExactTerminalsForWorktree: ['pty'],
+  stopTerminalsForWorktree: ['pty'],
+  stopTerminalsForProject: ['pty', 'structured-chat', 'host-browser', 'launch']
+}
+
+// Functions, `const` arrows and class members; a call or import matching it is harmless.
+const TEARDOWN_NAME =
+  /(?:^(?:export )?(?:async )?function |^(?:export )?(?:const|let) |^\s+(?:(?:async|private|protected|public|override|static|abstract|readonly) )*)((?:stop|close|teardown|kill|sleep|retire|forget)\w*For(?:Worktree|Project)s?)\b/gm
+
+function declaredTeardownFunctions(dir: string): string[] {
+  return readdirSync(dir, { withFileTypes: true }).flatMap((entry) => {
+    const path = join(dir, entry.name)
+    if (entry.isDirectory()) {
+      return declaredTeardownFunctions(path)
+    }
+    if (!entry.name.endsWith('.ts') || /\.(test|spec)\.ts$|\.test-fixture\.ts$/.test(entry.name)) {
+      return []
+    }
+    return [...readFileSync(path, 'utf8').matchAll(TEARDOWN_NAME)].map((match) => match[1])
+  })
+}
+
+describe('owned-session teardown walk', () => {
+  const declared = new Set(declaredTeardownFunctions(__dirname))
+
+  it('classifies every stop, close and teardown of a workspace in src/main/runtime', () => {
+    expect([...declared].filter((name) => !(name in TEARDOWN_FUNCTIONS)).sort()).toEqual([])
+    expect(Object.keys(TEARDOWN_FUNCTIONS).filter((name) => !declared.has(name))).toEqual([])
+  })
+
+  it('reaches every owned-session kind', () => {
+    const reached = new Set(Object.values(TEARDOWN_FUNCTIONS).flat())
+    expect(OWNED_SESSION_KINDS.filter((kind) => !reached.has(kind))).toEqual([])
+  })
 })
diff --git a/src/main/runtime/terminal/stop/project-terminal-stop.ts b/src/main/runtime/terminal/stop/project-terminal-stop.ts
index 1ac942109c4..3b16c32e831 100644
--- a/src/main/runtime/terminal/stop/project-terminal-stop.ts
+++ b/src/main/runtime/terminal/stop/project-terminal-stop.ts
@@ -170,11 +170,12 @@ export abstract class OrcaRuntimeWithStopTerminalsForProject extends OrcaRuntime
     if (this.projectSiblingSharesFence(repo)) {
       return { stopped: 0, worktreeIds: [] }
     }
-    let stopped = 0
     for (const id of listProjectTerminalWorktreeIds(repo.id, this.leaves, this.ptysById)) {
       projectWorktreeIds.add(id)
     }
-    for (const id of projectWorktreeIds) {
+    // Why all at once: one deadline covers the project, so a slow worktree must not spend the
+    // budget its siblings' stops need; each still holds only its own worktree's lock.
+    const stopWorktree = async (id: string): Promise<number> => {
       const opts = { resolvedWorktreeId: id, ...fence, ...options, requestStopsPastDeadline: true }
       // Why exclusive: it waits out a spawn that holds the shared lease, so its PTY is registered
       // and stopped. Bounded by the deadline so repo.rm still answers; past it PTYs are only asked.
@@ -190,11 +191,32 @@ export abstract class OrcaRuntimeWithStopTerminalsForProject extends OrcaRuntime
           this.stopTerminalsForWorktree(`id:${id}`, opts),
           options.deadline
         )
-        stopped += result?.stopped ?? 0
+        return result?.stopped ?? 0
       } finally {
         release?.()
       }
     }
+    // Why rounds: the inventory refresh may still add workspaces after its own budget gave up.
+    const started = new Set<string>()
+    const stops: PromiseSettledResult<number>[] = []
+    for (;;) {
+      const added = [...projectWorktreeIds].filter((id) => !started.has(id))
+      if (added.length === 0) {
+        break
+      }
+      for (const id of added) {
+        started.add(id)
+      }
+      stops.push(...(await Promise.allSettled(added.map(stopWorktree))))
+    }
+    const failure = stops.find((stop) => stop.status === 'rejected')
+    if (failure) {
+      throw failure.reason
+    }
+    const stopped = stops.reduce(
+      (total, stop) => total + (stop.status === 'fulfilled' ? stop.value : 0),
+      0
+    )
     return { stopped, worktreeIds: [...projectWorktreeIds] }
   }