diff --git a/components/extensions/general/BookDirectlyDialog.tsx b/components/extensions/general/BookDirectlyDialog.tsx
index 1151583d..10e5ddbc 100644
--- a/components/extensions/general/BookDirectlyDialog.tsx
+++ b/components/extensions/general/BookDirectlyDialog.tsx
@@ -14,8 +14,9 @@ import { Label } from '@/components/ui/label'
 import { Textarea } from '@/components/ui/textarea'
 import { Badge } from '@/components/ui/badge'
 import { useToast } from '@/components/ui/use-toast'
-import { Loader2, Plus, Trash2, AlertTriangle, Search, Check, BookmarkPlus } from 'lucide-react'
+import { Loader2, Plus, Trash2, Search, Check, BookmarkPlus } from 'lucide-react'
 import { cn, formatCurrency } from '@/lib/utils'
+import { roundOre } from '@/lib/money'
 import AccountCombobox from '@/components/bookkeeping/AccountCombobox'
 import { loadBasCatalog, type CatalogAccount } from '@/lib/bookkeeping/bas-catalog-client'
 import DocumentViewerPane from '@/components/bookkeeping/DocumentViewerPane'
@@ -533,6 +534,37 @@ export default function BookDirectlyDialog({ open, onOpenChange, item, docUrl =
     setLines((prev) => prev.length <= 2 ? prev : prev.filter((_, i) => i !== idx))
   }, [])
 
+  // Outstanding imbalance from every line except `excludeIndex`.
+  // Positive => debit side is short (a debit on the target row balances it);
+  // negative => credit side is short. Same semantics as JournalEntryForm.
+  const computeBalancingDiff = useCallback(
+    (excludeIndex: number) => {
+      const others = lines.filter((_, i) => i !== excludeIndex)
+      const d = others.reduce((sum, l) => sum + (parseFloat(l.debit_amount) || 0), 0)
+      const c = others.reduce((sum, l) => sum + (parseFloat(l.credit_amount) || 0), 0)
+      return roundOre(c - d)
+    },
+    [lines]
+  )
+
+  // Opt-in balancing (ported from JournalEntryForm): double-click a debit or
+  // credit field to fill the amount that makes the entry balance. No-op if
+  // already balanced or if the balancing entry belongs on the other side.
+  const handleFillBalance = useCallback(
+    (idx: number, side: 'debit' | 'credit') => {
+      const diff = computeBalancingDiff(idx)
+      const fill = side === 'debit' ? diff : -diff
+      if (fill <= 0) return
+      updateLine(
+        idx,
+        side === 'debit'
+          ? { debit_amount: fill.toFixed(2), credit_amount: '' }
+          : { credit_amount: fill.toFixed(2), debit_amount: '' }
+      )
+    },
+    [computeBalancingDiff, updateLine]
+  )
+
   // Replace the line set with a booking template's computed rows. The picker
   // hands back JournalEntryForm-shaped lines; we keep only the three fields
   // book-direct posts. A meaningful supplier description is preserved: the
@@ -879,6 +911,7 @@ export default function BookDirectlyDialog({ open, onOpenChange, item, docUrl =
                           inputMode="decimal"
                           value={line.debit_amount}
                           onChange={(e) => updateLine(idx, { debit_amount: e.target.value, credit_amount: e.target.value ? '' : line.credit_amount })}
+                          onDoubleClick={() => handleFillBalance(idx, 'debit')}
                           disabled={isSubmitting}
                           className="text-right tabular-nums"
                           placeholder="0,00"
@@ -891,6 +924,7 @@ export default function BookDirectlyDialog({ open, onOpenChange, item, docUrl =
                           inputMode="decimal"
                           value={line.credit_amount}
                           onChange={(e) => updateLine(idx, { credit_amount: e.target.value, debit_amount: e.target.value ? '' : line.debit_amount })}
+                          onDoubleClick={() => handleFillBalance(idx, 'credit')}
                           disabled={isSubmitting}
                           className="text-right tabular-nums"
                           placeholder="0,00"
@@ -914,13 +948,36 @@ export default function BookDirectlyDialog({ open, onOpenChange, item, docUrl =
                 </tbody>
                 <tfoot className="bg-muted/20 text-xs">
                   <tr>
-                    <td className="px-3 py-2 text-right font-medium uppercase tracking-wider text-muted-foreground">
-                      Summa
+                    <td className="px-3 py-2">
+                      <div className="flex items-center justify-between gap-3">
+                        {/* The remaining debit/credit gap, right where the user
+                            reconciles the sums: what is still missing to balance. */}
+                        {totals.diff !== 0 ? (
+                          <span className="tabular-nums font-medium text-destructive">
+                            Differens {Math.abs(totals.diff).toFixed(2)}
+                          </span>
+                        ) : (
+                          <span />
+                        )}
+                        <span className="text-right font-medium uppercase tracking-wider text-muted-foreground">
+                          Summa
+                        </span>
+                      </div>
                     </td>
-                    <td className="px-3 py-2 text-right tabular-nums font-medium">
+                    <td
+                      className={cn(
+                        'px-3 py-2 text-right tabular-nums font-medium',
+                        totals.diff !== 0 && 'text-destructive'
+                      )}
+                    >
                       {totals.debit.toFixed(2)}
                     </td>
-                    <td className="px-3 py-2 text-right tabular-nums font-medium">
+                    <td
+                      className={cn(
+                        'px-3 py-2 text-right tabular-nums font-medium',
+                        totals.diff !== 0 && 'text-destructive'
+                      )}
+                    >
                       {totals.credit.toFixed(2)}
                     </td>
                     <td />
@@ -969,12 +1026,11 @@ export default function BookDirectlyDialog({ open, onOpenChange, item, docUrl =
                 <Badge variant="success" className="text-[11px]">
                   Balanserad
                 </Badge>
-              ) : (
-                <span className="text-xs text-muted-foreground flex items-center gap-1.5 tabular-nums">
-                  <AlertTriangle className="h-3.5 w-3.5 text-warning" />
-                  Diff {totals.diff.toFixed(2)}
+              ) : totals.diff !== 0 ? (
+                <span className="text-xs text-muted-foreground">
+                  Dubbelklicka i ett tomt beloppsfält för att fylla i differensen
                 </span>
-              )}
+              ) : null}
             </div>
           </div>