diff --git a/web/src/components/SessionList.tsx b/web/src/components/SessionList.tsx
index 0c64b565..294fcc36 100644
--- a/web/src/components/SessionList.tsx
+++ b/web/src/components/SessionList.tsx
@@ -10,6 +10,7 @@ import { ConfirmDialog } from '@/components/ui/ConfirmDialog'
 import { CopyIcon, CheckIcon } from '@/components/icons'
 import { cn } from '@/lib/utils'
 import { useTranslation } from '@/lib/use-translation'
+import { DEFAULT_SESSION_PREVIEW_LIMIT, useSessionPreviewLimit } from '@/hooks/useSessionPreviewLimit'
 
 type SessionGroup = {
     key: string
@@ -91,7 +92,7 @@ function getGroupDisplayName(directory: string): string {
 }
 
 export const UNKNOWN_MACHINE_ID = '__unknown__'
-export const GROUP_SESSION_PREVIEW_LIMIT = 8
+export const GROUP_SESSION_PREVIEW_LIMIT = DEFAULT_SESSION_PREVIEW_LIMIT
 
 export function deduplicateSessionsByAgentId(sessions: SessionSummary[], selectedSessionId?: string | null): SessionSummary[] {
     const byAgentId = new Map<string, SessionSummary[]>()
@@ -698,6 +699,7 @@ export function SessionList(props: {
 }) {
     const { t } = useTranslation()
     const { renderHeader = true, api, selectedSessionId, machineLabelsById = {}, onNewSessionInDirectory } = props
+    const { sessionPreviewLimit } = useSessionPreviewLimit()
     const [searchQuery, setSearchQuery] = useState('')
     const normalizedQuery = normalizeSearch(searchQuery)
     const isSearching = normalizedQuery.length > 0
@@ -756,7 +758,7 @@ export function SessionList(props: {
     }
 
     const isSessionGroupExpanded = (group: SessionGroup): boolean => {
-        if (isSearching || group.sessions.length <= GROUP_SESSION_PREVIEW_LIMIT) return true
+        if (isSearching || group.sessions.length <= sessionPreviewLimit) return true
         const key = `sessions::${group.key}`
         const override = collapseOverrides.get(key)
         if (override !== undefined) return !override
@@ -778,7 +780,8 @@ export function SessionList(props: {
             group.sessions,
             {
                 expanded: isSessionGroupExpanded(group),
-                selectedSessionId
+                selectedSessionId,
+                limit: sessionPreviewLimit
             }
         )
     }
@@ -955,7 +958,7 @@ export function SessionList(props: {
                                                                 selected={s.id === selectedSessionId}
                                                             />
                                                         ))}
-                                                        {!isSearching && group.sessions.length > GROUP_SESSION_PREVIEW_LIMIT && (sessionGroupExpanded || hiddenSessionCount > 0) ? (
+                                                        {!isSearching && group.sessions.length > sessionPreviewLimit && (sessionGroupExpanded || hiddenSessionCount > 0) ? (
                                                             <button
                                                                 type="button"
                                                                 onClick={() => toggleSessionGroup(group)}
diff --git a/web/src/hooks/useSessionPreviewLimit.test.ts b/web/src/hooks/useSessionPreviewLimit.test.ts
new file mode 100644
index 00000000..87bd592b
--- /dev/null
+++ b/web/src/hooks/useSessionPreviewLimit.test.ts
@@ -0,0 +1,41 @@
+import { beforeEach, describe, expect, it } from 'vitest'
+import {
+    DEFAULT_SESSION_PREVIEW_LIMIT,
+    MAX_SESSION_PREVIEW_LIMIT,
+    MIN_SESSION_PREVIEW_LIMIT,
+    getInitialSessionPreviewLimit,
+    normalizeSessionPreviewLimit,
+} from './useSessionPreviewLimit'
+
+describe('useSessionPreviewLimit helpers', () => {
+    beforeEach(() => {
+        window.localStorage.clear()
+    })
+
+    it('falls back to the default for missing or invalid values', () => {
+        expect(getInitialSessionPreviewLimit()).toBe(DEFAULT_SESSION_PREVIEW_LIMIT)
+
+        window.localStorage.setItem('hapi-session-preview-limit', 'invalid')
+        expect(getInitialSessionPreviewLimit()).toBe(DEFAULT_SESSION_PREVIEW_LIMIT)
+
+        window.localStorage.setItem('hapi-session-preview-limit', '12.5')
+        expect(getInitialSessionPreviewLimit()).toBe(DEFAULT_SESSION_PREVIEW_LIMIT)
+    })
+
+    it('reads valid stored values', () => {
+        window.localStorage.setItem('hapi-session-preview-limit', '12')
+
+        expect(getInitialSessionPreviewLimit()).toBe(12)
+    })
+
+    it('clamps values to the supported range', () => {
+        expect(normalizeSessionPreviewLimit(0)).toBe(MIN_SESSION_PREVIEW_LIMIT)
+        expect(normalizeSessionPreviewLimit(120)).toBe(MAX_SESSION_PREVIEW_LIMIT)
+
+        window.localStorage.setItem('hapi-session-preview-limit', '0')
+        expect(getInitialSessionPreviewLimit()).toBe(MIN_SESSION_PREVIEW_LIMIT)
+
+        window.localStorage.setItem('hapi-session-preview-limit', '120')
+        expect(getInitialSessionPreviewLimit()).toBe(MAX_SESSION_PREVIEW_LIMIT)
+    })
+})
diff --git a/web/src/hooks/useSessionPreviewLimit.ts b/web/src/hooks/useSessionPreviewLimit.ts
new file mode 100644
index 00000000..1f6f7ce5
--- /dev/null
+++ b/web/src/hooks/useSessionPreviewLimit.ts
@@ -0,0 +1,117 @@
+import { useCallback, useEffect, useState } from 'react'
+
+export const DEFAULT_SESSION_PREVIEW_LIMIT = 8
+export const MIN_SESSION_PREVIEW_LIMIT = 1
+export const MAX_SESSION_PREVIEW_LIMIT = 99
+const SESSION_PREVIEW_LIMIT_CHANGED_EVENT = 'hapi-session-preview-limit-changed'
+
+function getSessionPreviewLimitStorageKey(): string {
+    return 'hapi-session-preview-limit'
+}
+
+function isBrowser(): boolean {
+    return typeof window !== 'undefined' && typeof document !== 'undefined'
+}
+
+function safeGetItem(key: string): string | null {
+    if (!isBrowser()) {
+        return null
+    }
+    try {
+        return localStorage.getItem(key)
+    } catch {
+        return null
+    }
+}
+
+function safeSetItem(key: string, value: string): void {
+    if (!isBrowser()) {
+        return
+    }
+    try {
+        localStorage.setItem(key, value)
+    } catch {
+        // Ignore storage errors
+    }
+}
+
+function safeRemoveItem(key: string): void {
+    if (!isBrowser()) {
+        return
+    }
+    try {
+        localStorage.removeItem(key)
+    } catch {
+        // Ignore storage errors
+    }
+}
+
+export function normalizeSessionPreviewLimit(value: number): number {
+    if (!Number.isInteger(value)) {
+        return DEFAULT_SESSION_PREVIEW_LIMIT
+    }
+    return Math.min(MAX_SESSION_PREVIEW_LIMIT, Math.max(MIN_SESSION_PREVIEW_LIMIT, value))
+}
+
+function parseSessionPreviewLimit(raw: string | null): number {
+    if (raw === null || raw.trim() === '') {
+        return DEFAULT_SESSION_PREVIEW_LIMIT
+    }
+    const value = Number(raw)
+    return normalizeSessionPreviewLimit(value)
+}
+
+export function getInitialSessionPreviewLimit(): number {
+    return parseSessionPreviewLimit(safeGetItem(getSessionPreviewLimitStorageKey()))
+}
+
+export function useSessionPreviewLimit(): {
+    sessionPreviewLimit: number
+    setSessionPreviewLimit: (limit: number) => void
+} {
+    const [sessionPreviewLimit, setSessionPreviewLimitState] = useState<number>(getInitialSessionPreviewLimit)
+
+    useEffect(() => {
+        if (!isBrowser()) {
+            return
+        }
+
+        const onStorage = (event: StorageEvent) => {
+            if (event.key !== getSessionPreviewLimitStorageKey()) {
+                return
+            }
+            setSessionPreviewLimitState(parseSessionPreviewLimit(event.newValue))
+        }
+
+        const onLocalChange = (event: Event) => {
+            const next = event instanceof CustomEvent ? event.detail : null
+            if (typeof next === 'number') {
+                setSessionPreviewLimitState(normalizeSessionPreviewLimit(next))
+            }
+        }
+
+        window.addEventListener('storage', onStorage)
+        window.addEventListener(SESSION_PREVIEW_LIMIT_CHANGED_EVENT, onLocalChange)
+        return () => {
+            window.removeEventListener('storage', onStorage)
+            window.removeEventListener(SESSION_PREVIEW_LIMIT_CHANGED_EVENT, onLocalChange)
+        }
+    }, [])
+
+    const setSessionPreviewLimit = useCallback((limit: number) => {
+        const normalized = normalizeSessionPreviewLimit(limit)
+        setSessionPreviewLimitState(normalized)
+
+        if (normalized === DEFAULT_SESSION_PREVIEW_LIMIT) {
+            safeRemoveItem(getSessionPreviewLimitStorageKey())
+        } else {
+            safeSetItem(getSessionPreviewLimitStorageKey(), String(normalized))
+        }
+
+        if (isBrowser()) {
+            window.dispatchEvent(new CustomEvent(SESSION_PREVIEW_LIMIT_CHANGED_EVENT, { detail: normalized }))
+        }
+    }, [])
+
+    return { sessionPreviewLimit, setSessionPreviewLimit }
+}
diff --git a/web/src/lib/locales/en.ts b/web/src/lib/locales/en.ts
index deba651a..c0bf00ce 100644
--- a/web/src/lib/locales/en.ts
+++ b/web/src/lib/locales/en.ts
@@ -374,6 +374,9 @@ export default {
   'settings.display.appearance.light': 'Light',
   'settings.display.fontSize': 'Font Size',
   'settings.display.terminalFontSize': 'Terminal Font Size',
+  'settings.display.sessionPreviewLimit': 'Sessions Before Folding',
+  'settings.display.sessionPreviewLimit.decrease': 'Show fewer sessions before folding',
+  'settings.display.sessionPreviewLimit.increase': 'Show more sessions before folding',
   'settings.chat.title': 'Chat',
   'settings.chat.enterBehavior': 'Enter Key',
   'settings.chat.enterBehavior.send': 'Send message',
diff --git a/web/src/lib/locales/zh-CN.ts b/web/src/lib/locales/zh-CN.ts
index 82fc8c03..1b767676 100644
--- a/web/src/lib/locales/zh-CN.ts
+++ b/web/src/lib/locales/zh-CN.ts
@@ -376,6 +376,9 @@ export default {
   'settings.display.appearance.light': '浅色',
   'settings.display.fontSize': '字体大小',
   'settings.display.terminalFontSize': '终端字体大小',
+  'settings.display.sessionPreviewLimit': '会话折叠阈值',
+  'settings.display.sessionPreviewLimit.decrease': '减少折叠前显示的会话数',
+  'settings.display.sessionPreviewLimit.increase': '增加折叠前显示的会话数',
   'settings.chat.title': '聊天',
   'settings.chat.enterBehavior': '回车键行为',
   'settings.chat.enterBehavior.send': '发送消息',
diff --git a/web/src/routes/settings/index.test.tsx b/web/src/routes/settings/index.test.tsx
index c3d2a000..daf059a4 100644
--- a/web/src/routes/settings/index.test.tsx
+++ b/web/src/routes/settings/index.test.tsx
@@ -51,6 +51,13 @@ vi.mock('@/hooks/useTerminalToolDisplayMode', () => ({
     ],
 }))
 
+vi.mock('@/hooks/useSessionPreviewLimit', () => ({
+    MIN_SESSION_PREVIEW_LIMIT: 1,
+    MAX_SESSION_PREVIEW_LIMIT: 99,
+    normalizeSessionPreviewLimit: (value: number) => Number.isInteger(value) ? Math.min(99, Math.max(1, value)) : 8,
+    useSessionPreviewLimit: () => ({ sessionPreviewLimit: 8, setSessionPreviewLimit: vi.fn() }),
+}))
+
 vi.mock('@/hooks/useChatSurfaceColors', () => ({
     useChatSurfaceColors: () => ({
         toolGroupBackground: 'default',
@@ -170,6 +177,9 @@ describe('SettingsPage', () => {
         const calledKeys = spyT.mock.calls.map((call) => call[0])
         expect(calledKeys).toContain('settings.display.appearance')
         expect(calledKeys).toContain('settings.display.appearance.system')
+        expect(calledKeys).toContain('settings.display.sessionPreviewLimit')
+        expect(calledKeys).toContain('settings.display.sessionPreviewLimit.decrease')
+        expect(calledKeys).toContain('settings.display.sessionPreviewLimit.increase')
     })
 
     it('renders the Terminal Font Size setting', () => {
@@ -178,6 +188,14 @@ describe('SettingsPage', () => {
         expect(screen.getAllByText('13px').length).toBeGreaterThanOrEqual(1)
     })
 
+    it('renders the Session Preview Limit setting', () => {
+        renderWithProviders(<SettingsPage />)
+        expect(screen.getAllByText('Sessions Before Folding').length).toBeGreaterThanOrEqual(1)
+        expect(screen.getByLabelText('Sessions Before Folding')).toHaveValue(8)
+        expect(screen.getAllByLabelText('Show fewer sessions before folding').length).toBeGreaterThanOrEqual(1)
+        expect(screen.getAllByLabelText('Show more sessions before folding').length).toBeGreaterThanOrEqual(1)
+    })
+
     it('renders the Enter Key setting', () => {
         renderWithProviders(<SettingsPage />)
         expect(screen.getAllByText('Enter Key').length).toBeGreaterThanOrEqual(1)
diff --git a/web/src/routes/settings/index.tsx b/web/src/routes/settings/index.tsx
index a3e6d00a..78dc263d 100644
--- a/web/src/routes/settings/index.tsx
+++ b/web/src/routes/settings/index.tsx
@@ -6,6 +6,12 @@ import { getFontScaleOptions, useFontScale, type FontScale } from '@/hooks/useFo
 import { getTerminalFontSizeOptions, useTerminalFontSize, type TerminalFontSize } from '@/hooks/useTerminalFontSize'
 import { getComposerEnterBehaviorOptions, useComposerEnterBehavior, type ComposerEnterBehavior } from '@/hooks/useComposerEnterBehavior'
 import { getTerminalToolDisplayModeOptions, useTerminalToolDisplayMode, type TerminalToolDisplayMode } from '@/hooks/useTerminalToolDisplayMode'
+import {
+    MAX_SESSION_PREVIEW_LIMIT,
+    MIN_SESSION_PREVIEW_LIMIT,
+    normalizeSessionPreviewLimit,
+    useSessionPreviewLimit,
+} from '@/hooks/useSessionPreviewLimit'
 import {
     getChatSurfaceColorPickerValue,
     getChatSurfaceColorPresetOptions,
@@ -82,6 +88,125 @@ function ChevronDownIcon(props: { className?: string }) {
     )
 }
 
+function MinusIcon(props: { className?: string }) {
+    return (
+        <svg
+            xmlns="http://www.w3.org/2000/svg"
+            width="16"
+            height="16"
+            viewBox="0 0 24 24"
+            fill="none"
+            stroke="currentColor"
+            strokeWidth="2"
+            strokeLinecap="round"
+            strokeLinejoin="round"
+            className={props.className}
+        >
+            <line x1="5" y1="12" x2="19" y2="12" />
+        </svg>
+    )
+}
+
+function PlusIcon(props: { className?: string }) {
+    return (
+        <svg
+            xmlns="http://www.w3.org/2000/svg"
+            width="16"
+            height="16"
+            viewBox="0 0 24 24"
+            fill="none"
+            stroke="currentColor"
+            strokeWidth="2"
+            strokeLinecap="round"
+            strokeLinejoin="round"
+            className={props.className}
+        >
+            <line x1="12" y1="5" x2="12" y2="19" />
+            <line x1="5" y1="12" x2="19" y2="12" />
+        </svg>
+    )
+}
+
+function SessionPreviewLimitControl(props: {
+    label: string
+    value: number
+    onChange: (value: number) => void
+    decreaseLabel: string
+    increaseLabel: string
+}) {
+    const [draft, setDraft] = useState(String(props.value))
+
+    useEffect(() => {
+        setDraft(String(props.value))
+    }, [props.value])
+
+    const commitDraft = () => {
+        const parsed = draft.trim() === '' ? props.value : Number(draft)
+        const next = normalizeSessionPreviewLimit(parsed)
+        props.onChange(next)
+        setDraft(String(next))
+    }
+
+    const step = (delta: number) => {
+        const next = normalizeSessionPreviewLimit(props.value + delta)
+        props.onChange(next)
+        setDraft(String(next))
+    }
+
+    return (
+        <div className="flex w-full items-center justify-between gap-3 px-3 py-3">
+            <label htmlFor="session-preview-limit" className="text-[var(--app-fg)]">
+                {props.label}
+            </label>
+            <div className="flex h-9 shrink-0 items-center rounded-lg border border-[var(--app-border)] bg-[var(--app-bg)] shadow-sm">
+                <button
+                    type="button"
+                    onClick={() => step(-1)}
+                    disabled={props.value <= MIN_SESSION_PREVIEW_LIMIT}
+                    aria-label={props.decreaseLabel}
+                    title={props.decreaseLabel}
+                    className="flex h-8 w-8 items-center justify-center rounded-l-lg text-[var(--app-hint)] transition-colors hover:bg-[var(--app-subtle-bg)] hover:text-[var(--app-fg)] disabled:cursor-not-allowed disabled:opacity-40"
+                >
+                    <MinusIcon className="h-3.5 w-3.5" />
+                </button>
+                <input
+                    id="session-preview-limit"
+                    type="number"
+                    inputMode="numeric"
+                    min={MIN_SESSION_PREVIEW_LIMIT}
+                    max={MAX_SESSION_PREVIEW_LIMIT}
+                    value={draft}
+                    onChange={(event) => setDraft(event.target.value)}
+                    onBlur={commitDraft}
+                    onKeyDown={(event) => {
+                        if (event.key === 'Enter') {
+                            event.preventDefault()
+                            commitDraft()
+                            event.currentTarget.blur()
+                        }
+                        if (event.key === 'Escape') {
+                            event.preventDefault()
+                            setDraft(String(props.value))
+                            event.currentTarget.blur()
+                        }
+                    }}
+                    className="h-8 w-14 border-x border-[var(--app-border)] bg-transparent text-center text-sm font-medium tabular-nums text-[var(--app-fg)] outline-none focus:bg-[var(--app-subtle-bg)]"
+                />
+                <button
+                    type="button"
+                    onClick={() => step(1)}
+                    disabled={props.value >= MAX_SESSION_PREVIEW_LIMIT}
+                    aria-label={props.increaseLabel}
+                    title={props.increaseLabel}
+                    className="flex h-8 w-8 items-center justify-center rounded-r-lg text-[var(--app-hint)] transition-colors hover:bg-[var(--app-subtle-bg)] hover:text-[var(--app-fg)] disabled:cursor-not-allowed disabled:opacity-40"
+                >
+                    <PlusIcon className="h-3.5 w-3.5" />
+                </button>
+            </div>
+        </div>
+    )
+}
+
 function ChatSurfaceColorControl(props: {
     label: string
     preference: ChatSurfaceColorPreference
@@ -158,6 +283,7 @@ export default function SettingsPage() {
     const voiceContainerRef = useRef<HTMLDivElement>(null)
     const { fontScale, setFontScale } = useFontScale()
     const { terminalFontSize, setTerminalFontSize } = useTerminalFontSize()
+    const { sessionPreviewLimit, setSessionPreviewLimit } = useSessionPreviewLimit()
     const { composerEnterBehavior, setComposerEnterBehavior } = useComposerEnterBehavior()
     const { terminalToolDisplayMode, setTerminalToolDisplayMode } = useTerminalToolDisplayMode()
     const {
@@ -499,6 +625,13 @@ export default function SettingsPage() {
                                 </div>
                             )}
                         </div>
+                        <SessionPreviewLimitControl
+                            label={t('settings.display.sessionPreviewLimit')}
+                            value={sessionPreviewLimit}
+                            onChange={setSessionPreviewLimit}
+                            decreaseLabel={t('settings.display.sessionPreviewLimit.decrease')}
+                            increaseLabel={t('settings.display.sessionPreviewLimit.increase')}
+                        />
                     </div>
 
                     {/* Chat section */}