diff --git a/src/food-market.api/Background/ReferencePriceRefreshJob.cs b/src/food-market.api/Background/ReferencePriceRefreshJob.cs
new file mode 100644
index 0000000..505d523
--- /dev/null
+++ b/src/food-market.api/Background/ReferencePriceRefreshJob.cs
@@ -0,0 +1,60 @@
+using foodmarket.Infrastructure.Persistence;
+using Microsoft.EntityFrameworkCore;
+
+namespace foodmarket.Api.Background;
+
+/// <summary>Раз в сутки переписывает ReferencePrice = Cost для товаров,
+/// у которых LastSupplyAt старше 30 дней и Cost > 0. Цель: устаревшая
+/// «эталонная» цена не остаётся годами — её сравнивают с актуальной
+/// себестоимостью. Если пользователь редактировал ReferencePrice вручную
+/// (через PUT /api/catalog/products/...), ReferencePriceUpdatedAt уходит
+/// в now, и таймер начинает 30 дней заново.</summary>
+public class ReferencePriceRefreshJob : BackgroundService
+{
+    private readonly IServiceProvider _services;
+    private readonly ILogger<ReferencePriceRefreshJob> _log;
+    // Запускаем каждые 24 часа. Промах между сутками не критичен — цена
+    // не падает, а лишь догоняет текущую Cost.
+    private static readonly TimeSpan Period = TimeSpan.FromHours(24);
+
+    public ReferencePriceRefreshJob(IServiceProvider services, ILogger<ReferencePriceRefreshJob> log)
+    {
+        _services = services;
+        _log = log;
+    }
+
+    protected override async Task ExecuteAsync(CancellationToken ct)
+    {
+        // Ждём 5 минут после старта чтобы не упасть на ещё не применённой миграции.
+        try { await Task.Delay(TimeSpan.FromMinutes(5), ct); } catch (TaskCanceledException) { return; }
+
+        using var timer = new PeriodicTimer(Period);
+        do
+        {
+            try { await RunOnceAsync(ct); }
+            catch (Exception ex) { _log.LogError(ex, "ReferencePriceRefreshJob: iteration failed"); }
+        }
+        while (await timer.WaitForNextTickAsync(ct));
+    }
+
+    public async Task RunOnceAsync(CancellationToken ct)
+    {
+        using var scope = _services.CreateScope();
+        var db = scope.ServiceProvider.GetRequiredService<AppDbContext>();
+        var threshold = DateTime.UtcNow.AddDays(-30);
+        // IgnoreQueryFilters — фоновый job работает над всеми organizations.
+        var stale = await db.Products
+            .IgnoreQueryFilters()
+            .Where(p => p.LastSupplyAt != null && p.LastSupplyAt < threshold && p.Cost > 0m)
+            .ToListAsync(ct);
+        if (stale.Count == 0) return;
+        var now = DateTime.UtcNow;
+        foreach (var p in stale)
+        {
+            p.ReferencePrice = p.Cost;
+            p.ReferencePriceUpdatedAt = now;
+        }
+        await db.SaveChangesAsync(ct);
+        _log.LogInformation("ReferencePriceRefreshJob: refreshed {Count} stale products", stale.Count);
+    }
+}
diff --git a/src/food-market.api/Controllers/Catalog/ProductsController.cs b/src/food-market.api/Controllers/Catalog/ProductsController.cs
index 83a45b2..1bd9b05 100644
--- a/src/food-market.api/Controllers/Catalog/ProductsController.cs
+++ b/src/food-market.api/Controllers/Catalog/ProductsController.cs
@@ -273,6 +273,59 @@ public async Task<IActionResult> Update(Guid id, [FromBody] ProductInput input,
         return NoContent();
     }
 
+    /// <summary>«Привести розничную к себестоимости»: ставит дефолтную
+    /// розничную цену = ceil(Cost * (1 + Group.MarkupPercent/100)). Если у
+    /// группы товара не задан MarkupPercent — 400 с подсказкой.</summary>
+    [HttpPost("{id:guid}/recalc-retail"), Authorize(Roles = "Admin,Manager,Storekeeper")]
+    public async Task<IActionResult> RecalcRetail(Guid id, CancellationToken ct)
+    {
+        var p = await _db.Products
+            .Include(x => x.ProductGroup)
+            .Include(x => x.Prices)
+            .FirstOrDefaultAsync(x => x.Id == id, ct);
+        if (p is null) return NotFound();
+        if (p.ProductGroup?.MarkupPercent is not decimal pct)
+            return BadRequest(new { error = "У группы не задана наценка. Задайте её в настройках или введите цену вручную." });
+
+        var allowFractional = await AllowFractionalAsync(ct);
+        var raw = p.Cost * (1m + pct / 100m);
+        var newRetail = allowFractional
+            ? Math.Ceiling(raw * 100m) / 100m
+            : Math.Ceiling(raw);
+
+        var defaultType = await _db.PriceTypes
+            .Where(pt => pt.IsActive)
+            .OrderByDescending(pt => pt.IsDefault)
+            .ThenByDescending(pt => pt.IsRetail)
+            .ThenBy(pt => pt.SortOrder)
+            .ThenBy(pt => pt.Name)
+            .FirstOrDefaultAsync(ct);
+        if (defaultType is null)
+            return BadRequest(new { error = "Нет ни одного активного типа цен. Создайте его в настройках." });
+
+        var fallbackCurrency = await _db.Organizations.Select(o => o.DefaultCurrencyId).FirstOrDefaultAsync(ct)
+            ?? await _db.Currencies.OrderBy(c => c.Code).Select(c => (Guid?)c.Id).FirstOrDefaultAsync(ct);
+        if (fallbackCurrency is null)
+            return BadRequest(new { error = "Не задана валюта по умолчанию." });
+
+        var existing = p.Prices.FirstOrDefault(x => x.PriceTypeId == defaultType.Id);
+        if (existing is null)
+        {
+            p.Prices.Add(new ProductPrice
+            {
+                PriceTypeId = defaultType.Id,
+                Amount = newRetail,
+                CurrencyId = fallbackCurrency.Value,
+            });
+        }
+        else
+        {
+            existing.Amount = newRetail;
+        }
+        await _db.SaveChangesAsync(ct);
+        return Ok(new { retail = newRetail });
+    }
+
     [HttpDelete("{id:guid}"), Authorize(Roles = "Admin,Manager")]
     public async Task<IActionResult> Delete(Guid id, CancellationToken ct)
     {
diff --git a/src/food-market.api/Program.cs b/src/food-market.api/Program.cs
index 5538013..e1431f4 100644
--- a/src/food-market.api/Program.cs
+++ b/src/food-market.api/Program.cs
@@ -138,6 +138,7 @@
     builder.Services.AddHostedService<OpenIddictClientSeeder>();
     builder.Services.AddHostedService<SystemReferenceSeeder>();
     builder.Services.AddHostedService<DevDataSeeder>();
+    builder.Services.AddHostedService<foodmarket.Api.Background.ReferencePriceRefreshJob>();
     // DemoCatalogSeeder disabled: real catalog is imported from MoySklad.
     // Keep the file as reference for anyone starting without MoySklad access —
     // just re-register here to turn demo data back on.