diff --git a/apps/web/src/app/shared/grid/lines-grid.html b/apps/web/src/app/shared/grid/lines-grid.html
index 05bda82..e2e6ad5 100644
--- a/apps/web/src/app/shared/grid/lines-grid.html
+++ b/apps/web/src/app/shared/grid/lines-grid.html
@@ -14,11 +14,11 @@
     <thead>
       <tr>
         <th class="rn">#</th>
-        @for (c of columns(); track c.key) {
+        @for (c of columns(); track c.key; let j = $index) {
           <th sboColResize [style.width]="c.width" [style.text-align]="alignOf(c)" [class.req]="c.required">{{ c.title }}</th>
-        }
-        @if (hasDetails()) {
-          <th class="det">Lotes / Series</th>
+          @if (hasDetails() && j === detailAt()) {
+            <th class="det">Lotes / Series</th>
+          }
         }
         @if (!readonly()) {
           <th class="del"><span class="sr">Quitar</span></th>
@@ -69,13 +69,13 @@
                 />
               }
             </td>
-          }
-          @if (hasDetails()) {
-            <td class="det">
-              @for (d of detailsOf(line); track d.key) {
-                <button type="button" class="detbtn" [attr.aria-label]="d.title + ' de la línea ' + (i + 1)" (click)="openDetail(i, d)">{{ d.summary(line) }}</button>
-              }
-            </td>
+            @if (hasDetails() && j === detailAt()) {
+              <td class="det">
+                @for (d of detailsOf(line); track d.key) {
+                  <button type="button" class="detbtn" [attr.aria-label]="d.title + ' de la línea ' + (i + 1)" (click)="openDetail(i, d)">{{ d.summary(line) }}</button>
+                }
+              </td>
+            }
           }
           @if (!readonly()) {
             <td class="del">
diff --git a/apps/web/src/app/shared/grid/lines-grid.spec.ts b/apps/web/src/app/shared/grid/lines-grid.spec.ts
index d9862fd..364f169 100644
--- a/apps/web/src/app/shared/grid/lines-grid.spec.ts
+++ b/apps/web/src/app/shared/grid/lines-grid.spec.ts
@@ -580,3 +580,37 @@ describe('LinesGrid: detalles de línea (lotes)', () => {
     expect(el.querySelector('sbo-line-detail-dialog footer .btn.main')).toBeNull();
   });
 });
+
+describe('LinesGrid: dónde va la columna de lotes y series', () => {
+  @Component({
+    imports: [LinesGrid],
+    template: `<sbo-lines-grid [columns]="columns" [(lines)]="lines" [newLine]="newLine" [details]="details" />`,
+  })
+  class PlaceHost {
+    columns = [
+      { key: 'ItemCode', title: 'Artículo' },
+      { key: 'Quantity', title: 'Cantidad', type: 'number' as const },
+      { key: 'Price', title: 'Precio', type: 'number' as const },
+      { key: 'CostingCode', title: 'Dim. 1' },
+    ];
+    lines = signal<readonly GridLine[]>([{ ItemCode: 'SU01', Quantity: 1, _manageBatches: true }]);
+    newLine = () => ({});
+    details = [{ key: 'BatchNumbers', title: 'Lotes', applies: () => true, columns: [], summary: () => 'Indicar lotes' }];
+  }
+
+  it('va justo después de la cantidad, no al final tras todas las demás columnas', async () => {
+    await TestBed.configureTestingModule({ imports: [PlaceHost], providers: [provideHttpClient(), provideHttpClientTesting()] }).compileComponents();
+    const fixture = TestBed.createComponent(PlaceHost);
+    fixture.detectChanges();
+    await fixture.whenStable();
+    fixture.detectChanges();
+    const el = fixture.nativeElement as HTMLElement;
+    const heads = [...el.querySelectorAll('thead th')].map((t) => t.textContent?.trim());
+    expect(heads.slice(1, 5)).toEqual(['Artículo', 'Cantidad', 'Lotes / Series', 'Precio']);
+    const cells = [...el.querySelectorAll('tbody tr:first-child td')];
+    expect(cells[3].classList.contains('det')).toBe(true);
+    expect(cells[3].textContent?.trim()).toBe('Indicar lotes');
+    // los índices de columna (teclado) no cuentan la columna de lotes
+    expect(el.querySelector('input[data-r="0"][data-c="2"]')).toBeTruthy();
+  });
+});
diff --git a/apps/web/src/app/shared/grid/lines-grid.ts b/apps/web/src/app/shared/grid/lines-grid.ts
index 29ed822..3a8a779 100644
--- a/apps/web/src/app/shared/grid/lines-grid.ts
+++ b/apps/web/src/app/shared/grid/lines-grid.ts
@@ -68,6 +68,12 @@ export class LinesGrid {
   protected readonly multiOpen = signal(false);
   protected readonly lookup = computed(() => this.lookupTarget()?.column.lookup?.config);
   protected readonly hasDetails = computed(() => this.details().length > 0);
+  /** Posición de la columna «Lotes / Series»: justo después de la cantidad (si no hay, al final). */
+  protected readonly detailAt = computed(() => {
+    const cols = this.columns();
+    const q = cols.findIndex((c) => c.key === 'Quantity');
+    return q >= 0 ? q : cols.length - 1;
+  });
   /** Filas con que se abre la ventana (estable mientras no cambie la línea: la ventana edita una copia). */
   protected readonly detailInitial = computed<readonly Record<string, unknown>[]>(() => {
     const t = this.detailTarget();