diff --git a/feature/afternote/presentation/src/main/kotlin/com/afternote/feature/afternote/presentation/editor/AfternoteEditorRouteHelpers.kt b/feature/afternote/presentation/src/main/kotlin/com/afternote/feature/afternote/presentation/editor/AfternoteEditorRouteHelpers.kt
index 91b441a69..517276782 100644
--- a/feature/afternote/presentation/src/main/kotlin/com/afternote/feature/afternote/presentation/editor/AfternoteEditorRouteHelpers.kt
+++ b/feature/afternote/presentation/src/main/kotlin/com/afternote/feature/afternote/presentation/editor/AfternoteEditorRouteHelpers.kt
@@ -34,6 +34,10 @@ internal fun AfternoteEditorError.messageResId(): Int =
             R.string.afternote_editor_prefill_not_ready
         }
 
+        AfternoteEditorError.MediaSizeExceeded -> {
+            R.string.afternote_editor_media_size_exceeded
+        }
+
         is AfternoteEditorError.Upload -> {
             when (target) {
                 AfternoteEditorError.Upload.Target.THUMBNAIL -> R.string.afternote_editor_thumbnail_upload_failed
diff --git a/feature/afternote/presentation/src/main/kotlin/com/afternote/feature/afternote/presentation/editor/AfternoteEditorViewModel.kt b/feature/afternote/presentation/src/main/kotlin/com/afternote/feature/afternote/presentation/editor/AfternoteEditorViewModel.kt
index 08ef70304..c092b9b49 100644
--- a/feature/afternote/presentation/src/main/kotlin/com/afternote/feature/afternote/presentation/editor/AfternoteEditorViewModel.kt
+++ b/feature/afternote/presentation/src/main/kotlin/com/afternote/feature/afternote/presentation/editor/AfternoteEditorViewModel.kt
@@ -4,6 +4,7 @@ import android.util.Log
 import androidx.lifecycle.SavedStateHandle
 import androidx.lifecycle.viewModelScope
 import com.afternote.core.common.reporting.ErrorReporter
+import com.afternote.core.domain.error.FileUploadFailure
 import com.afternote.core.domain.repository.UserReceiverRepository
 import com.afternote.core.domain.result.runCatchingCancellable
 import com.afternote.core.ui.mvi.MviViewModel
@@ -899,9 +900,13 @@ private fun Throwable.toAfternoteEditorError(): AfternoteEditorError =
     when (this) {
         is AfternoteFailure -> {
             when (this) {
-                // 미디어 해석 실패는 사용자가 입력을 고쳐 푸는 검증 실패가 아니라 업로드 장애다.
+                // 크기 초과는 같은 파일의 재전송으로 풀리지 않으므로 일반 업로드 실패와 구분한다.
                 is AfternoteFailure.MediaSave -> {
-                    AfternoteEditorError.Upload(AfternoteEditorError.Upload.Target.SAVE_MEDIA)
+                    if (cause is FileUploadFailure.FileSizeExceeded) {
+                        AfternoteEditorError.MediaSizeExceeded
+                    } else {
+                        AfternoteEditorError.Upload(AfternoteEditorError.Upload.Target.SAVE_MEDIA)
+                    }
                 }
 
                 is AfternoteFailure.NetworkUnavailable -> {
diff --git a/feature/afternote/presentation/src/main/kotlin/com/afternote/feature/afternote/presentation/editor/state/AfternoteSaveState.kt b/feature/afternote/presentation/src/main/kotlin/com/afternote/feature/afternote/presentation/editor/state/AfternoteSaveState.kt
index e155b25d5..42252bce9 100644
--- a/feature/afternote/presentation/src/main/kotlin/com/afternote/feature/afternote/presentation/editor/state/AfternoteSaveState.kt
+++ b/feature/afternote/presentation/src/main/kotlin/com/afternote/feature/afternote/presentation/editor/state/AfternoteSaveState.kt
@@ -71,6 +71,9 @@ sealed interface AfternoteEditorError {
      */
     data object PrefillNotReady : AfternoteEditorError
 
+    /** 사진·영상 파일이 서버의 업로드 한도를 초과했다. 같은 파일의 재시도를 안내하지 않는다. */
+    data object MediaSizeExceeded : AfternoteEditorError
+
     data class Upload(
         val target: Target,
     ) : AfternoteEditorError {
diff --git a/feature/afternote/presentation/src/main/res/values/strings.xml b/feature/afternote/presentation/src/main/res/values/strings.xml
index dfc816b61..195f92e31 100644
--- a/feature/afternote/presentation/src/main/res/values/strings.xml
+++ b/feature/afternote/presentation/src/main/res/values/strings.xml
@@ -156,6 +156,7 @@
          말하지 않는다 — 곧 도착하므로 기다리면 저장할 수 있다. -->
     <string name="afternote_editor_prefill_not_ready">기존 내용을 불러오는 중입니다.\n잠시 후 다시 시도해 주세요.</string>
     <string name="afternote_editor_prefill_retry">다시 불러오기</string>
+    <string name="afternote_editor_media_size_exceeded">파일 크기가 업로드 허용 한도를 초과했습니다.</string>
     <string name="afternote_editor_thumbnail_upload_failed">영상 미리보기를 올리지 못했습니다.</string>
     <string name="afternote_editor_thumbnail_extract_failed">영상에서 미리보기를 만들지 못했습니다.</string>
     <string name="afternote_editor_thumbnail_retry">다시 시도</string>
diff --git a/feature/afternote/presentation/src/test/kotlin/com/afternote/feature/afternote/presentation/editor/AfternoteEditorMediaSizeExceededTest.kt b/feature/afternote/presentation/src/test/kotlin/com/afternote/feature/afternote/presentation/editor/AfternoteEditorMediaSizeExceededTest.kt
new file mode 100644
index 000000000..66b382e47
--- /dev/null
+++ b/feature/afternote/presentation/src/test/kotlin/com/afternote/feature/afternote/presentation/editor/AfternoteEditorMediaSizeExceededTest.kt
@@ -0,0 +1,196 @@
+package com.afternote.feature.afternote.presentation.editor
+
+import com.afternote.core.domain.error.FileUploadFailure
+import com.afternote.feature.afternote.domain.AfternoteType
+import com.afternote.feature.afternote.domain.repository.author.MediaInput
+import com.afternote.feature.afternote.domain.repository.author.MediaKind
+import com.afternote.feature.afternote.domain.repository.author.MemorialMediaUploadRepository
+import com.afternote.feature.afternote.domain.repository.author.MemorialThumbnailUploadRepository
+import com.afternote.feature.afternote.domain.testing.FakeAfternoteRepository
+import com.afternote.feature.afternote.domain.usecase.editor.ResolveMemorialMediaForSaveUseCase
+import com.afternote.feature.afternote.domain.usecase.editor.SaveAfternoteUseCase
+import com.afternote.feature.afternote.presentation.NoopAuthorErrorReporter
+import com.afternote.feature.afternote.presentation.R
+import com.afternote.feature.afternote.presentation.afternoteAuthorUserReceiverRepository
+import com.afternote.feature.afternote.presentation.afternoteEditorSavedStateHandle
+import com.afternote.feature.afternote.presentation.editor.model.RegisterAfternotePayload
+import com.afternote.feature.afternote.presentation.editor.state.AfternoteEditorError
+import com.afternote.feature.afternote.presentation.editor.state.EditableMemorialPhoto
+import com.afternote.feature.afternote.presentation.editor.state.EditableMemorialVideo
+import com.afternote.feature.afternote.presentation.editor.state.EditorFormState
+import com.afternote.feature.afternote.presentation.editorFlowRoute
+import kotlinx.coroutines.Dispatchers
+import kotlinx.coroutines.ExperimentalCoroutinesApi
+import kotlinx.coroutines.test.StandardTestDispatcher
+import kotlinx.coroutines.test.advanceUntilIdle
+import kotlinx.coroutines.test.resetMain
+import kotlinx.coroutines.test.runTest
+import kotlinx.coroutines.test.setMain
+import org.junit.After
+import org.junit.Assert.assertEquals
+import org.junit.Assert.assertFalse
+import org.junit.Assert.assertNotEquals
+import org.junit.Assert.assertNull
+import org.junit.Assert.assertTrue
+import org.junit.Before
+import org.junit.Test
+import org.junit.runner.RunWith
+import org.robolectric.RobolectricTestRunner
+import org.robolectric.annotation.Config
+import java.io.IOException
+
+/**
+ * 업로드 크기 초과(서버 code 1803)를 일반 저장 실패와 가른다 (#1868).
+ *
+ * 크기 초과는 재시도로 풀리지 않는 유일한 업로드 실패다 — 같은 파일을 다시 보내면 서버가 같은
+ * 코드로 다시 거절한다. 「저장에 실패했습니다」 로 뭉쳐 두면 사용자는 파일을 바꿔야 풀린다는 것도,
+ * 기다렸다 다시 눌러 봐야 소용없다는 것도 알 수 없다.
+ *
+ * 진입은 공개 [AfternoteEditorIntent.Save] 하나이고, 실패는 실제 [ResolveMemorialMediaForSaveUseCase]
+ * 를 통과해 온다 — 매핑만 직접 불러 확인하면 UseCase 가 cause 를 다르게 감싸도 초록으로 남는다.
+ */
+@OptIn(ExperimentalCoroutinesApi::class)
+@RunWith(RobolectricTestRunner::class)
+@Config(sdk = [35])
+class AfternoteEditorMediaSizeExceededTest {
+    private val dispatcher = StandardTestDispatcher()
+
+    @Before
+    fun setUp() {
+        Dispatchers.setMain(dispatcher)
+    }
+
+    @After
+    fun tearDown() {
+        Dispatchers.resetMain()
+    }
+
+    @Test
+    fun `영상이 한도를 넘으면 저장을 보내지 않고 크기 초과로 알린다`() {
+        assertResolveFailure(
+            failingKind = MediaKind.VIDEO,
+            uploadFailure = fileSizeExceeded(),
+            expected = AfternoteEditorError.MediaSizeExceeded,
+        )
+    }
+
+    @Test
+    fun `사진이 한도를 넘으면 저장을 보내지 않고 크기 초과로 알린다`() {
+        assertResolveFailure(
+            failingKind = MediaKind.PHOTO,
+            uploadFailure = fileSizeExceeded(),
+            expected = AfternoteEditorError.MediaSizeExceeded,
+        )
+    }
+
+    /**
+     * 갈래를 늘리면서 기존 안내를 뭉개지 않았는지 본다 — 사유를 확인하지 못한 업로드 실패는
+     * data 계층이 치환하지 않고 원본 그대로 흘려보내므로, 여기서도 종전 일반 오류로 남아야 한다.
+     */
+    @Test
+    fun `사유를 모르는 업로드 실패는 기존 저장 미디어 오류로 남는다`() {
+        assertResolveFailure(
+            failingKind = MediaKind.VIDEO,
+            uploadFailure = IOException("connection reset"),
+            expected = AfternoteEditorError.Upload(AfternoteEditorError.Upload.Target.SAVE_MEDIA),
+        )
+    }
+
+    @Test
+    fun `크기 초과는 일반 저장 실패와 다른 문구로 나가고 다시 시도를 권하지 않는다`() {
+        assertEquals(
+            R.string.afternote_editor_media_size_exceeded,
+            AfternoteEditorError.MediaSizeExceeded.messageResId(),
+        )
+        assertNotEquals(
+            "크기 초과가 일반 저장 실패와 같은 문구로 나가면 파일을 바꿔야 한다는 사실이 사라진다",
+            AfternoteEditorError.Upload(AfternoteEditorError.Upload.Target.SAVE_MEDIA).messageResId(),
+            AfternoteEditorError.MediaSizeExceeded.messageResId(),
+        )
+        assertFalse(
+            "같은 파일을 다시 보내면 서버가 같은 코드로 거절한다 — 재시도 액션을 붙이면 안 된다",
+            AfternoteEditorError.MediaSizeExceeded.offersMemorialThumbnailRetry(),
+        )
+    }
+
+    /**
+     * @param failingKind 업로드가 거절당하는 매체. 영상이 먼저 해석되므로 사진 갈래는 영상이
+     *   통과한 뒤에야 도달한다 ([ResolveMemorialMediaForSaveUseCase]).
+     */
+    private fun assertResolveFailure(
+        failingKind: MediaKind,
+        uploadFailure: Throwable,
+        expected: AfternoteEditorError,
+    ) = runTest(dispatcher) {
+        // strict fake — 저장 요청이 한 줄이라도 나가면 그 자리에서 터진다.
+        val repository = FakeAfternoteRepository.strict()
+        val viewModel = viewModel(repository, failingKind, uploadFailure)
+        viewModel.onIntent(AfternoteEditorIntent.SetMemorialPhoto(PHOTO_URI))
+        viewModel.onIntent(AfternoteEditorIntent.SetMemorialVideo(VIDEO_URI))
+
+        val pickedMedia =
+            viewModel.uiState.value.form
+                .memorialMediaForSave()
+        viewModel.onIntent(
+            AfternoteEditorIntent.Save(
+                payload = RegisterAfternotePayload(serviceName = "추억 노트", date = "2026.09.20"),
+                selectedReceiverIds = emptyList(),
+                memorialMedia = pickedMedia,
+            ),
+        )
+        advanceUntilIdle()
+
+        val state = viewModel.uiState.value
+        assertEquals(expected, state.error)
+        assertFalse("업로드에서 끊겼는데 저장 중 표시가 남으면 등록 버튼이 잠긴 채로 굳는다", state.isSaving)
+        assertNull(state.savedId)
+        // 업로드에서 끊겼으니 저장 요청 자체가 나가지 않는다 — 나갔다면 payload 가 기록된다.
+        assertTrue("미디어를 못 올렸는데 저장이 나가면 미디어 없는 기록이 확정된다", repository.memorialPayloads.isEmpty())
+        // 고른 파일은 그대로 둔다 — 한도를 넘긴 쪽만 바꿔 다시 저장할 수 있어야 한다.
+        assertEquals(PHOTO_URI, state.form.displayMemorialPhotoUri())
+        assertEquals(VIDEO_URI, state.form.displayedMemorialVideo?.url)
+    }
+
+    private fun viewModel(
+        repository: FakeAfternoteRepository,
+        failingKind: MediaKind,
+        uploadFailure: Throwable,
+    ): AfternoteEditorViewModel {
+        val savedStateHandle = afternoteEditorSavedStateHandle(initialType = AfternoteType.MEMORIAL)
+        return AfternoteEditorViewModel(
+            route = savedStateHandle.editorFlowRoute(),
+            savedStateHandle = savedStateHandle,
+            userReceiverRepository = afternoteAuthorUserReceiverRepository(),
+            afternoteRepository = repository,
+            memorialThumbnailUploadRepository =
+                MemorialThumbnailUploadRepository { error("썸네일 업로드가 호출되면 안 됩니다") },
+            resolveMemorialMediaForSave =
+                ResolveMemorialMediaForSaveUseCase(
+                    MemorialMediaUploadRepository { input, kind ->
+                        when {
+                            kind == failingKind -> Result.failure(uploadFailure)
+                            input is MediaInput.Local -> Result.success("https://cdn.test/${kind.name.lowercase()}")
+                            else -> Result.success(null)
+                        }
+                    },
+                ),
+            saveAfternoteUseCase = SaveAfternoteUseCase(repository),
+            errorReporter = NoopAuthorErrorReporter,
+        )
+    }
+
+    /** 서버 봉투의 code 1803 을 data 계층이 옮겨 놓은 모양 — presentation 은 이 타입만 보고 가른다. */
+    private fun fileSizeExceeded(): FileUploadFailure.FileSizeExceeded =
+        FileUploadFailure.FileSizeExceeded(IllegalStateException("code=1803 FILE_SIZE_EXCEEDED"))
+
+    private fun EditorFormState.memorialMediaForSave(): SaveAfternoteMemorialMedia =
+        SaveAfternoteMemorialMedia(
+            memorialVideo = memorialVideo ?: EditableMemorialVideo.empty(),
+            memorialPhoto = memorialPhoto ?: EditableMemorialPhoto.empty(),
+        )
+
+    private companion object {
+        const val PHOTO_URI = "content://photos/portrait"
+        const val VIDEO_URI = "content://videos/farewell"
+    }
+}
diff --git a/feature/afternote/presentation/src/test/kotlin/com/afternote/feature/afternote/presentation/editor/AfternoteEditorSnackbarActionTest.kt b/feature/afternote/presentation/src/test/kotlin/com/afternote/feature/afternote/presentation/editor/AfternoteEditorSnackbarActionTest.kt
index eda7c4876..000ac7e48 100644
--- a/feature/afternote/presentation/src/test/kotlin/com/afternote/feature/afternote/presentation/editor/AfternoteEditorSnackbarActionTest.kt
+++ b/feature/afternote/presentation/src/test/kotlin/com/afternote/feature/afternote/presentation/editor/AfternoteEditorSnackbarActionTest.kt
@@ -24,6 +24,8 @@ class AfternoteEditorSnackbarActionTest {
     fun `저장 실패와 그 밖의 오류에는 썸네일 재시도가 붙지 않는다`() {
         listOf(
             AfternoteEditorError.Upload(Target.SAVE_MEDIA),
+            // 크기 초과는 재시도로 풀리지 않는 유일한 업로드 실패다 — 다시 보내면 서버가 같은 코드로 거절한다 (#1868).
+            AfternoteEditorError.MediaSizeExceeded,
             AfternoteEditorError.Network,
             AfternoteEditorError.Server,
             AfternoteEditorError.ReceiverSelectionUnavailable,