diff --git a/src/main/java/com/interplug/qcast/batch/JobLauncherController.java b/src/main/java/com/interplug/qcast/batch/JobLauncherController.java
index 189a7cf6..bcac883b 100644
--- a/src/main/java/com/interplug/qcast/batch/JobLauncherController.java
+++ b/src/main/java/com/interplug/qcast/batch/JobLauncherController.java
@@ -163,9 +163,11 @@ public class JobLauncherController {
   /**
    * BOM 아이템 동기화 배치
    *
-
+   * [2026-05-13] 04:20 으로 이동 (estimateSyncJob 과 시간 스왑).
+   * 사유: estimateSyncJob 이 만성 timeout 으로 길어질 수 있어, 새벽 마지막 슬롯(05:20)으로 옮김.
+   * BOM 은 GET 단일 호출(0.7초 수준)이라 슬롯 영향 無.
    */
-  @Scheduled(cron = "0 20 05 * * *")
+  @Scheduled(cron = "0 20 04 * * *")
   public String bomJob() throws JobInstanceAlreadyCompleteException, JobExecutionAlreadyRunningException, JobParametersInvalidException, JobRestartException {
 
     return executeScheduledJob("bomJob");
@@ -246,9 +248,12 @@ public class JobLauncherController {
   /**
    * 견적서 전송 동기화 배치
    *
-
+   * [2026-05-13] 05:20 으로 이동 (bomJob 과 시간 스왑).
+   * 사유: 만성 QSP timeout 으로 chunk 분할 송신해도 길어질 수 있어, 새벽 마지막 슬롯에 배치.
+   * 다음 스케줄(23:50 storeAdditionalJob)까지 18시간 버퍼 확보 → 후속 job 침범 위험 제거.
+   * chunk 분할 로직은 EstimateSyncConfiguration 참고.
    */
-  @Scheduled(cron = "0 20 04 * * *")
+  @Scheduled(cron = "0 20 05 * * *")
   public String estimateSyncJob() throws JobInstanceAlreadyCompleteException, JobExecutionAlreadyRunningException, JobParametersInvalidException, JobRestartException {
 
     return executeScheduledJob("estimateSyncJob");
diff --git a/src/main/java/com/interplug/qcast/batch/estimate/EstimateSyncConfiguration.java b/src/main/java/com/interplug/qcast/batch/estimate/EstimateSyncConfiguration.java
index 801d0a73..d2fe4604 100644
--- a/src/main/java/com/interplug/qcast/batch/estimate/EstimateSyncConfiguration.java
+++ b/src/main/java/com/interplug/qcast/batch/estimate/EstimateSyncConfiguration.java
@@ -1,12 +1,15 @@
 package com.interplug.qcast.batch.estimate;
 
 import com.interplug.qcast.biz.estimate.EstimateService;
+import com.interplug.qcast.biz.estimate.dto.EstimateSendRequest;
+import com.interplug.qcast.biz.estimate.dto.EstimateSendResponse;
 import com.interplug.qcast.biz.estimate.dto.EstimateSyncResponse;
 import com.interplug.qcast.biz.estimate.dto.PlanSyncResponse;
 import com.interplug.qcast.util.InterfaceQsp;
 import java.util.ArrayList;
 import java.util.Collections;
 import java.util.List;
+import lombok.extern.slf4j.Slf4j;
 import org.springframework.batch.core.Job;
 import org.springframework.batch.core.JobExecutionListener;
 import org.springframework.batch.core.Step;
@@ -24,17 +27,24 @@ import org.springframework.http.HttpMethod;
 import org.springframework.transaction.PlatformTransactionManager;
 
 /** Plan 확정 Item 마스터 동기화 배치 */
+@Slf4j
 @Configuration
 public class EstimateSyncConfiguration implements JobExecutionListener {
   private final EstimateService estimateService;
 
   private final InterfaceQsp interfaceQsp;
 
-  EstimateSyncResponse estimateSyncResponse;
-
   @Value("${qsp.estimate-sync-batch-url}")
   private String qspInterfaceUrl;
 
+  // [2026-05-13] QSP 견적 동기화 chunk 크기 — 만성 120s timeout 회피 위해 분할 송신
+  @Value("${qsp.estimate-sync-chunk-size:50}")
+  private int estimateSyncChunkSize;
+
+  // [2026-05-13] 총 송신 시간 상한 (밀리초). 초과 시 남은 chunk 중단하여 다음 스케줄 job (04:50 materialJob) 침범 방지.
+  @Value("${qsp.estimate-sync-total-timeout-ms:1500000}")
+  private long estimateSyncTotalTimeoutMs;
+
   public EstimateSyncConfiguration(EstimateService estimateService, InterfaceQsp interfaceQsp) {
     this.estimateService = estimateService;
     this.interfaceQsp = interfaceQsp;
@@ -59,15 +69,94 @@ public class EstimateSyncConfiguration implements JobExecutionListener {
   @Bean
   @StepScope
   public ListItemReader<PlanSyncResponse> estimateSyncReader() throws Exception {
-    this.estimateSyncResponse =
-        interfaceQsp.callApiData(
-            HttpMethod.POST,
-            qspInterfaceUrl,
-            estimateService.selectEstimateSyncFailList(),
-            EstimateSyncResponse.class);
-    return (estimateSyncResponse != null)
-        ? new ListItemReader<>(estimateSyncResponse.getSuccessList())
-        : new ListItemReader<>(Collections.emptyList());
+    // [2026-05-13] 만성 timeout 회피: 전체 fail list 를 한 번에 POST 하지 않고 chunk 단위로 분할 송신.
+    // 각 chunk 는 try/catch — 일부 chunk 실패해도 다음 chunk 진행.
+    // 모든 chunk 실패 시에만 throw 하여 Step FAILED.
+    // 총 elapsed 가 상한 초과 시 남은 chunk 중단 (다음 스케줄 job 침범 방지).
+    EstimateSendRequest fullRequest = estimateService.selectEstimateSyncFailList();
+    List<EstimateSendResponse> quoteList =
+        (fullRequest != null) ? fullRequest.getQuoteList() : null;
+
+    if (quoteList == null || quoteList.isEmpty()) {
+      log.info("QSP 견적 동기화: 송신할 fail list 없음");
+      return new ListItemReader<>(Collections.emptyList());
+    }
+
+    int chunkSize = Math.max(1, estimateSyncChunkSize);
+    int totalChunks = (quoteList.size() + chunkSize - 1) / chunkSize;
+    List<PlanSyncResponse> mergedSuccessList = new ArrayList<>();
+    int successChunks = 0;
+    int abortedChunks = 0;
+    long startAt = System.currentTimeMillis();
+
+    log.info(
+        "QSP 견적 동기화 분할 송신 시작: totalItems={}, chunkSize={}, totalChunks={}",
+        quoteList.size(),
+        chunkSize,
+        totalChunks);
+
+    for (int i = 0; i < quoteList.size(); i += chunkSize) {
+      long elapsed = System.currentTimeMillis() - startAt;
+      if (elapsed > estimateSyncTotalTimeoutMs) {
+        abortedChunks = totalChunks - (i / chunkSize);
+        log.warn(
+            "QSP 견적 동기화 총 elapsed 상한 초과 — 남은 chunk 중단: elapsedMs={}, limitMs={}, abortedChunks={}",
+            elapsed,
+            estimateSyncTotalTimeoutMs,
+            abortedChunks);
+        break;
+      }
+
+      int end = Math.min(i + chunkSize, quoteList.size());
+      int chunkIndex = i / chunkSize;
+      List<EstimateSendResponse> sub = new ArrayList<>(quoteList.subList(i, end));
+      EstimateSendRequest subRequest = new EstimateSendRequest();
+      subRequest.setQuoteList(sub);
+
+      try {
+        EstimateSyncResponse chunkResponse =
+            interfaceQsp.callApiData(
+                HttpMethod.POST, qspInterfaceUrl, subRequest, EstimateSyncResponse.class);
+        if (chunkResponse != null && chunkResponse.getSuccessList() != null) {
+          mergedSuccessList.addAll(chunkResponse.getSuccessList());
+        }
+        successChunks++;
+        log.info(
+            "QSP 견적 동기화 chunk 성공: chunkIndex={}/{}, range=[{},{}), accumulatedSuccess={}",
+            chunkIndex,
+            totalChunks,
+            i,
+            end,
+            mergedSuccessList.size());
+      } catch (Exception e) {
+        log.error(
+            "QSP 견적 동기화 chunk 실패 — 다음 chunk 계속: chunkIndex={}/{}, range=[{},{})",
+            chunkIndex,
+            totalChunks,
+            i,
+            end,
+            e);
+      }
+    }
+
+    long totalElapsed = System.currentTimeMillis() - startAt;
+    log.info(
+        "QSP 견적 동기화 분할 송신 완료: totalChunks={}, successChunks={}, abortedChunks={}, mergedSuccess={}, totalElapsedMs={}",
+        totalChunks,
+        successChunks,
+        abortedChunks,
+        mergedSuccessList.size(),
+        totalElapsed);
+
+    if (successChunks == 0) {
+      throw new IllegalStateException(
+          "QSP 견적 동기화 모든 chunk 실패: totalChunks="
+              + totalChunks
+              + ", quoteSize="
+              + quoteList.size());
+    }
+
+    return new ListItemReader<>(mergedSuccessList);
   }
 
   @Bean