COGS Tracking Monthly: The Single Metric That Predicts Restaurant Failure

What COGS is and why it matters more than revenue#

Revenue tells you how busy you are. COGS tells you whether being busy is actually making you money. Cost of Goods Sold in a restaurant is the direct cost of the food and beverages consumed to generate your sales — what was bought, less what was left in stock. If you started the month with £8,000 of stock, bought £22,000 more, and ended with £6,500, your COGS was £23,500. If your revenue was £72,000, your gross margin was 67.4%. If your COGS was £26,000 on the same revenue, your gross margin was 63.9% — a 3.5 percentage point difference that translates to £2,520/month in lost margin. COGS is the denominator of every restaurant financial decision. Without it, you are running blind.

Why most restaurants do not track COGS properly#

Proper COGS calculation requires an accurate opening stock count, accurate recording of all purchases during the period, and an accurate closing stock count. Most restaurants do the middle part (they have supplier invoices), miss or approximate the stock counts, and therefore cannot calculate a true COGS figure. Instead, they use total purchases as a proxy for COGS — which is significantly less accurate because it ignores the change in stock value. A month where you stocked up for Christmas has high purchases but the stock is not consumed until December. Using purchases as COGS would overstate your costs in November and understate them in December. The distortion can be £2,000-£5,000 for a mid-size restaurant, making month-on-month comparisons meaningless.

Monthly COGS tracking with AskBiz#

AskBiz maintains a running stock value at all times: opening balance updated by deliveries received and reduced by sales (via recipe deductions from the POS) and waste logged. At end of month, AskBiz calculates COGS automatically: opening stock + purchases − closing stock count (you do a physical count to verify the system balance). The physical count takes 30-45 minutes for a mid-size restaurant when you are using AskBiz — because the system tells you what the balance should be, and you are spot-checking the high-value items rather than counting everything from scratch. The result: an accurate COGS figure available by the 5th of the following month at the latest, not the 25th when your accountant sends the management accounts.

Warning signs in monthly COGS trends#

The most valuable use of monthly COGS tracking is trend analysis. A single month of 35% COGS may be explainable — high wastage due to a quiet month, a one-off expensive event, a seasonal spike in ingredient prices. Three consecutive months of 35% COGS is a structural problem that needs investigation. AskBiz shows COGS percentage over the trailing 12 months as a line chart on the management dashboard. When the line starts trending up — from 30% to 31% to 32% over three months — it is visible before it reaches 35%. The early visibility allows intervention: recipe review, waste reduction initiative, supplier price negotiation. By the time month-end accounts arrive from your accountant, it is already too late to act on that month's COGS.

Separating food COGS from beverage COGS#

Food and beverage have different COGS benchmarks. Food typically runs 28-35% COGS for casual dining. Beverage — particularly wine and cocktails — should run 20-28% COGS. If you track them blended, a high-beverage-revenue Saturday evening artificially improves your apparent COGS (because drinks have lower cost percentages), masking a problem on the food side. Equally, if your bar is running 35% COGS on spirits (possible with premium cocktail programmes), blending it with food hides the bar's underperformance. AskBiz separates food and beverage inventory and reports COGS for each category independently. You can benchmark your kitchen and bar separately and intervene where the problem actually is.

COGS as a predictor of near-term viability#

Research on restaurant failure patterns consistently shows that rising COGS percentage is one of the earliest indicators — typically 4-6 months before cash flow becomes critical. The mechanism: rising COGS compresses gross margin, which compresses cash generation from operations, which reduces the buffer against fixed costs. A restaurant with a 68% gross margin has significant headroom to absorb a slow January. A restaurant with a 60% gross margin has very little. If COGS has been rising for three months before January, the restaurant enters the slow season with a structural disadvantage that the season itself exposes. Monthly COGS tracking through AskBiz identifies this trend while there is still time to act.

Sharing COGS data with your accountant effectively#

The most productive conversation you can have with your accountant is one where you both have the same timely data in front of you. When you present monthly COGS data by the 5th of each following month, your accountant can provide meaningful analysis — rather than retrospective commentary on accounts prepared on day 25. AskBiz exports a management accounts pack monthly: P&L with COGS breakdown, gross margin by category, stock movement report, and trend analysis over 12 months. This pack replaces the ad hoc data requests that typically delay management account preparation by two to three weeks. Faster accounts means faster decisions.

• Restaurants that close usually had visible warning signs 4-6 months before: COGS trending up, margin trending down, cash reserves thinning.
• The problem is they had no system to see these signals early.
• AskBiz tracks COGS monthly so you know in October what will become a crisis in January.