diff --git a/src/constants.ts b/src/constants.ts
index dbcf1bd3..d212c1bb 100644
--- a/src/constants.ts
+++ b/src/constants.ts
@@ -162,6 +162,20 @@ export const PUBLISH_MULTI_RELAY_CONNECTION_CAP_MS = 12_000
 /** Max merged URLs per REQ / timeline relay list (see `relay-url-priority`). */
 export const MAX_REQ_RELAY_URLS = MAX_CONCURRENT_RELAY_CONNECTIONS
 
+/** Session-park relays that finish REQ waves much slower than peers (see {@link relaySessionStrikes}). */
+export const RELAY_SLOW_PARK_ABSOLUTE_MS = 10_000
+/** Multiplier over batch median EOSE latency to count a relay as slow in multi-relay waves. */
+export const RELAY_SLOW_PARK_MEDIAN_MULTIPLIER = 2.5
+/** Slow signals within a session before omitting the relay from multi-relay read stacks. */
+export const RELAY_SLOW_PARK_SIGNALS_THRESHOLD = 2
+/** How long a session-parked slow relay stays out of multi-relay reads. */
+export const RELAY_SLOW_PARK_COOLDOWN_MS = 5 * 60 * 1000
+
+/** Close pooled WebSocket when no SUBs and no pool activity for this long (see {@link initRelayPoolIdle}). */
+export const RELAY_POOL_SOCKET_IDLE_MS = 90_000
+/** How often to scan for idle relay sockets. */
+export const RELAY_POOL_IDLE_SWEEP_INTERVAL_MS = 45_000
+
 /**
  * Maximum `kinds` length in a single NIP-01 filter. Some relays NOTICE "too many kinds" and reject the
  * entire REQ (e.g. strfry derivatives, relay.vukihreedia.xyz). QueryService splits larger arrays into
diff --git a/src/lib/relay-pool-idle.ts b/src/lib/relay-pool-idle.ts
new file mode 100644
index 00000000..62a9889c
--- /dev/null
+++ b/src/lib/relay-pool-idle.ts
@@ -0,0 +1,107 @@
+import { RELAY_POOL_IDLE_SWEEP_INTERVAL_MS, RELAY_POOL_SOCKET_IDLE_MS } from '@/constants'
+import logger from '@/lib/logger'
+import { canonicalRelaySessionKey, normalizeAnyRelayUrl } from '@/lib/url'
+import type { SimplePool } from 'nostr-tools'
+
+type HasActiveSubsFn = (canonicalRelayKey: string) => boolean
+
+let pool: SimplePool | null = null
+let hasActiveSubs: HasActiveSubsFn | null = null
+let sweepTimer: ReturnType<typeof setInterval> | null = null
+const lastActivityMs = new Map<string, number>()
+
+function canon(url: string): string {
+  return canonicalRelaySessionKey(normalizeAnyRelayUrl(url) || url.trim())
+}
+
+/** Mark relay URL as recently used (connect, REQ, publish). */
+export function touchRelayPoolActivity(url: string): void {
+  const key = canon(url)
+  if (!key) return
+  lastActivityMs.set(key, Date.now())
+}
+
+/**
+ * Wire idle socket sweeps to the app pool. Safe to call once from {@link ClientService} constructor.
+ */
+export function initRelayPoolIdle(nextPool: SimplePool, nextHasActiveSubs: HasActiveSubsFn): void {
+  pool = nextPool
+  hasActiveSubs = nextHasActiveSubs
+  if (sweepTimer != null) return
+  sweepTimer = setInterval(() => {
+    sweepIdleRelayPoolSockets()
+  }, RELAY_POOL_IDLE_SWEEP_INTERVAL_MS)
+}
+
+/** Close connected sockets that have no active SUBs and exceeded {@link RELAY_POOL_SOCKET_IDLE_MS}. */
+export function sweepIdleRelayPoolSockets(): void {
+  if (!pool || !hasActiveSubs) return
+  const now = Date.now()
+  let status: Map<string, boolean>
+  try {
+    status = pool.listConnectionStatus()
+  } catch {
+    return
+  }
+
+  const toClose: string[] = []
+  for (const [url, connected] of status) {
+    if (!connected) continue
+    const key = canon(url)
+    if (!key) continue
+    if (hasActiveSubs(key)) continue
+    const last = lastActivityMs.get(key) ?? 0
+    if (now - last < RELAY_POOL_SOCKET_IDLE_MS) continue
+    toClose.push(normalizeAnyRelayUrl(url) || url)
+  }
+
+  if (toClose.length === 0) return
+  try {
+    pool.close(toClose)
+    logger.debug('[RelayPoolIdle] closed idle sockets', { count: toClose.length, relays: toClose })
+  } catch {
+    /* ignore */
+  }
+  for (const url of toClose) {
+    lastActivityMs.delete(canon(url))
+  }
+}
+
+/** Close specific relays when they are connected, have no active SUBs, and are not session-parked hot. */
+export function closeRelayPoolSocketsIfIdle(urls: readonly string[]): void {
+  if (!pool || !hasActiveSubs || urls.length === 0) return
+  let status: Map<string, boolean>
+  try {
+    status = pool.listConnectionStatus()
+  } catch {
+    return
+  }
+
+  const toClose: string[] = []
+  for (const raw of urls) {
+    const key = canon(raw)
+    if (!key || hasActiveSubs(key)) continue
+    const normalized = normalizeAnyRelayUrl(raw) || raw
+    const connected = [...status.entries()].some(
+      ([u, ok]) => ok && canon(u) === key
+    )
+    if (connected) toClose.push(normalized)
+  }
+  if (toClose.length === 0) return
+  try {
+    pool.close(toClose)
+    logger.debug('[RelayPoolIdle] closed sockets after slow-park', { relays: toClose })
+  } catch {
+    /* ignore */
+  }
+}
+
+export function resetRelayPoolIdleForTests(): void {
+  if (sweepTimer != null) {
+    clearInterval(sweepTimer)
+    sweepTimer = null
+  }
+  pool = null
+  hasActiveSubs = null
+  lastActivityMs.clear()
+}
diff --git a/src/lib/relay-strikes.test.ts b/src/lib/relay-strikes.test.ts
new file mode 100644
index 00000000..3b57e46b
--- /dev/null
+++ b/src/lib/relay-strikes.test.ts
@@ -0,0 +1,44 @@
+import { describe, expect, it, beforeEach } from 'vitest'
+import { relaySessionStrikes } from './relay-strikes'
+import type { RelayOpTerminalRow } from '@/services/relay-operation-log.service'
+
+function row(
+  url: string,
+  outcome: RelayOpTerminalRow['outcome'],
+  msFromBatchStart: number
+): RelayOpTerminalRow {
+  return { cmdIndex: 0, relayUrl: url, outcome, msFromBatchStart }
+}
+
+describe('relaySessionStrikes.observeSubscribeBatch', () => {
+  beforeEach(() => {
+    relaySessionStrikes.reset()
+  })
+
+  it('session-parks a relay much slower than batch median after two slow waves', () => {
+    const slow = 'wss://slow.example.com/'
+    const fast = 'wss://fast.example.com/'
+
+    relaySessionStrikes.observeSubscribeBatch([
+      row(fast, 'eose', 400),
+      row(slow, 'eose', 12_000)
+    ])
+    expect(relaySessionStrikes.isReadHttpSkipped(slow)).toBe(false)
+
+    relaySessionStrikes.observeSubscribeBatch([
+      row(fast, 'eose', 500),
+      row(slow, 'eose', 11_000)
+    ])
+    expect(relaySessionStrikes.isReadHttpSkipped(slow)).toBe(true)
+    expect(relaySessionStrikes.isReadHttpSkipped(fast)).toBe(false)
+  })
+
+  it('clears slow parking on fast EOSE via recordReadSuccess', () => {
+    const url = 'wss://recover.example.com/'
+    relaySessionStrikes.observeSubscribeBatch([row(url, 'eose', 15_000)])
+    relaySessionStrikes.observeSubscribeBatch([row(url, 'eose', 14_000)])
+    expect(relaySessionStrikes.isReadHttpSkipped(url)).toBe(true)
+    relaySessionStrikes.recordReadSuccess(url)
+    expect(relaySessionStrikes.isReadHttpSkipped(url)).toBe(false)
+  })
+})
diff --git a/src/lib/relay-strikes.ts b/src/lib/relay-strikes.ts
index 460ce74a..78be33b8 100644
--- a/src/lib/relay-strikes.ts
+++ b/src/lib/relay-strikes.ts
@@ -1,7 +1,14 @@
+import {
+  RELAY_SLOW_PARK_ABSOLUTE_MS,
+  RELAY_SLOW_PARK_COOLDOWN_MS,
+  RELAY_SLOW_PARK_MEDIAN_MULTIPLIER,
+  RELAY_SLOW_PARK_SIGNALS_THRESHOLD
+} from '@/constants'
 import type { Event } from 'nostr-tools'
 import { getRelayListFromEvent } from '@/lib/event-metadata'
 import logger from '@/lib/logger'
 import { canonicalRelaySessionKey, isHttpRelayUrl } from '@/lib/url'
+import type { RelayOpTerminalRow } from '@/services/relay-operation-log.service'
 
 /** Conservative: 5 read/publish failures → skip until this many ms after last qualifying failure. */
 const STRIKE_FAILURES_THRESHOLD = 5
@@ -31,6 +38,8 @@ type StrikeEntry = {
   readFailures: number
   readLastStrikeIncrementAt: number
   readStrikeSkipUntil: number
+  slowSignals: number
+  slowParkUntil: number
   publishFailures: number
   publishLastStrikeIncrementAt: number
   publishStrikeSkipUntil: number
@@ -47,6 +56,8 @@ function emptyEntry(): StrikeEntry {
     readFailures: 0,
     readLastStrikeIncrementAt: 0,
     readStrikeSkipUntil: 0,
+    slowSignals: 0,
+    slowParkUntil: 0,
     publishFailures: 0,
     publishLastStrikeIncrementAt: 0,
     publishStrikeSkipUntil: 0,
@@ -103,7 +114,7 @@ class RelaySessionStrikes {
     if (!key) return false
     const e = this.byKey.get(key)
     if (!e) return false
-    return Date.now() < Math.max(e.rateLimitUntil, e.readStrikeSkipUntil)
+    return Date.now() < Math.max(e.rateLimitUntil, e.readStrikeSkipUntil, e.slowParkUntil)
   }
 
   /** True when publish should omit this relay (unless single-target override). */
@@ -172,6 +183,70 @@ class RelaySessionStrikes {
     e.readFailures = 0
     e.readStrikeSkipUntil = 0
     e.readLastStrikeIncrementAt = 0
+    e.slowSignals = 0
+    e.slowParkUntil = 0
+  }
+
+  /**
+   * After a subscribe/query wave: session-park relays that were much slower than peers (or timed out).
+   * Returns URLs whose pooled sockets should be closed when idle.
+   */
+  observeSubscribeBatch(rows: readonly RelayOpTerminalRow[]): string[] {
+    if (rows.length === 0) return []
+    const now = Date.now()
+    const socketsToClose: string[] = []
+
+    const eoseRows = rows.filter((r) => r.outcome === 'eose')
+    const sortedLatencies =
+      eoseRows.length > 0 ? [...eoseRows.map((r) => r.msFromBatchStart)].sort((a, b) => a - b) : []
+    const medianMs =
+      sortedLatencies.length > 0
+        ? sortedLatencies[Math.floor((sortedLatencies.length - 1) / 2)]!
+        : RELAY_SLOW_PARK_ABSOLUTE_MS
+
+    const slowThresholdMs =
+      rows.length > 1
+        ? Math.max(RELAY_SLOW_PARK_ABSOLUTE_MS, Math.round(medianMs * RELAY_SLOW_PARK_MEDIAN_MULTIPLIER))
+        : RELAY_SLOW_PARK_ABSOLUTE_MS
+
+    for (const row of rows) {
+      const key = sessionKey(row.relayUrl)
+      if (!key) continue
+
+      const timedOut = row.outcome === 'timeout'
+      const slowEose = row.outcome === 'eose' && row.msFromBatchStart >= slowThresholdMs
+      const fastEose = row.outcome === 'eose' && row.msFromBatchStart < slowThresholdMs * 0.6
+
+      if (timedOut || slowEose) {
+        const parked = this.recordSlowSignalKey(key, now)
+        if (parked) socketsToClose.push(row.relayUrl)
+        if (timedOut) this.recordReadFailureKey(key, 'connection')
+        continue
+      }
+
+      if (fastEose) {
+        const e = this.byKey.get(key)
+        if (e && e.slowSignals > 0) {
+          e.slowSignals = Math.max(0, e.slowSignals - 1)
+        }
+      }
+    }
+
+    return socketsToClose
+  }
+
+  private recordSlowSignalKey(key: string, now: number): boolean {
+    const e = this.getEntry(key)
+    if (this.cacheRelayKeys.has(key)) return false
+    e.slowSignals += 1
+    if (e.slowSignals < RELAY_SLOW_PARK_SIGNALS_THRESHOLD) return false
+    e.slowParkUntil = Math.max(e.slowParkUntil, now + RELAY_SLOW_PARK_COOLDOWN_MS)
+    logger.warn('[RelayStrikes] session-parked slow relay', {
+      key,
+      slowSignals: e.slowSignals,
+      cooldownMs: RELAY_SLOW_PARK_COOLDOWN_MS
+    })
+    return true
   }
 
   recordPublishFailure(url: string): void {
diff --git a/src/services/client-query.service.ts b/src/services/client-query.service.ts
index 938468c3..4d497af6 100644
--- a/src/services/client-query.service.ts
+++ b/src/services/client-query.service.ts
@@ -351,6 +351,13 @@ export class QueryService {
     }
   }
 
+  /** True when this relay still has at least one open REQ subscription (live timeline, etc.). */
+  relayHasActiveSubscriptions(relayKeyOrUrl: string): boolean {
+    const key = canonicalRelaySessionKey(normalizeUrl(relayKeyOrUrl) || relayKeyOrUrl.trim())
+    if (!key) return false
+    return (this.activeSubCountByRelay.get(key) ?? 0) > 0
+  }
+
   private canonicalSeenOnEventId(eventId: string): string {
     const t = eventId.trim()
     return /^[0-9a-f]{64}$/i.test(t) ? t.toLowerCase() : t
diff --git a/src/services/client.service.ts b/src/services/client.service.ts
index fcaa7537..d0c3a4ee 100644
--- a/src/services/client.service.ts
+++ b/src/services/client.service.ts
@@ -150,6 +150,7 @@ import {
 } from '@/lib/url'
 import { canonicalFeedFilter, canonicalRelayUrls } from '@/features/feed/descriptor'
 import { feedRelayPolicyUrls } from '@/features/feed/relay-policy'
+import { initRelayPoolIdle, touchRelayPoolActivity } from '@/lib/relay-pool-idle'
 import { relaySessionStrikes } from '@/lib/relay-strikes'
 import { isSafari } from '@/lib/utils'
 import {
@@ -421,6 +422,7 @@ class ClientService extends EventTarget {
       })
       patchPoolRelayAuthRaceAndFeedback(relay)
       applyRelayNip42AckTimeout(relay)
+      touchRelayPoolActivity(url)
       return relay
     }
 
@@ -456,6 +458,10 @@ class ClientService extends EventTarget {
       }
     })
     this.bookstrService = createBookstrService(this.queryService)
+
+    initRelayPoolIdle(this.pool, (relayKeyOrUrl) =>
+      this.queryService.relayHasActiveSubscriptions(relayKeyOrUrl)
+    )
   }
 
   public static getInstance(): ClientService {
diff --git a/src/services/relay-operation-log.service.ts b/src/services/relay-operation-log.service.ts
index 1a0b8fb3..b1c7fbcd 100644
--- a/src/services/relay-operation-log.service.ts
+++ b/src/services/relay-operation-log.service.ts
@@ -1,3 +1,5 @@
+import { closeRelayPoolSocketsIfIdle } from '@/lib/relay-pool-idle'
+import { relaySessionStrikes } from '@/lib/relay-strikes'
 import logger from '@/lib/logger'
 import { normalizeAnyRelayUrl } from '@/lib/url'
 import type { Filter } from 'nostr-tools'
@@ -307,6 +309,11 @@ export class RelaySubscribeOpBatch {
       }
     }
 
+    const parkedCloseUrls = relaySessionStrikes.observeSubscribeBatch(rows)
+    if (parkedCloseUrls.length > 0) {
+      closeRelayPoolSocketsIfIdle(parkedCloseUrls)
+    }
+
     this.onBatchEnd?.(rows)
   }
 }