Pour Cost vs GP Percentage: Which Matters More

Last updated: 26 June 2026

Most pub licensees get this backwards: they focus on pour cost and ignore GP percentage, when it’s actually the reverse that protects your bottom line. Pour cost tells you what you paid for the liquid. GP percentage tells you whether you made money. One is a component of the other — and knowing the difference will change how you read your weekly numbers.

I’ve watched licensees stress over a 28% pour cost on their draught lager while their spirits GP was collapsing without them noticing. The problem isn’t that they cared about cost. It’s that they were looking at the wrong number in isolation.

This guide explains what each metric actually means, why they’re not interchangeable, and which one you should wake up worried about on a Monday morning. You’ll also learn the single number that actually matters and the measurement mistake that costs most pubs between £3,000 and £5,000 a year without anyone knowing.

Pour Cost vs GP Percentage: The Core Difference

Pour cost is the cost of the liquid you sold, divided by the revenue from those sales, expressed as a percentage. If you sold £1,000 of draught beer and it cost you £300 to buy, your pour cost is 30%.

GP percentage (gross profit) is the profit you made on wet sales after the cost of stock, but before labour and overheads. If you sold £1,000 of draught beer, the cost was £300, and you wasted £50, your GP is £650 — a 65% GP percentage.

The critical difference: pour cost only looks at what you bought. GP percentage includes what you actually lost.

Here’s a real example from my own pub. I was running a spreadsheet that told me my average pour cost across all wet was 26%. It looked healthy. My GP percentage was closer to 58%. That gap — 2 percentage points — was costing me around £400 a month in variance I couldn’t explain. Once I started tracking cask dips, spirit bottle weights, and till reconciliation on the same day each week, I found out where it was going: 1% evaporation and wastage on draught, 0.5% on spirits from free-pouring drift, and the rest from kegs going off and partial bottles sitting too long.

The operation insight most pub owners don’t realise: your pubco rep will tell you your pour cost target. They won’t help you find the variance between cost and actual profit. That gap is where your money disappears.

Why Pour Cost Alone Is Misleading

Pour cost looks tidy because it only has two numbers: what you spent and what you sold. It’s the metric your pubco cares about because it’s easy to benchmark across pubs of the same size.

But it tells you nothing about whether you actually made money.

Scenario: Your pour cost is 28% on spirits. Your pubco says the target is 25%. You’re stressed. You start watering down, pushing less premium brands, negotiating with your rep. Your pour cost drops to 24%. You feel better.

But what if 2 percentage points of that variance wasn’t poor purchasing? What if it was free-pouring? Over-measurement? Stock sitting too long and going cloudy? Your pour cost improved, but you didn’t fix the actual problem.

Worse: if your GP percentage on spirits was already 62%, you didn’t need to reduce pour cost at all. You were making good money. You fixed something that wasn’t broken and probably annoyed your customers in the process.

Pour cost only answers one question: “Am I buying stock at the right price?” It doesn’t answer: “Am I selling it without losing it?”

Why GP Percentage Is the Real Health Check

GP percentage tells you whether the operation is actually working. It includes every loss: waste, spillage, evaporation, measurement error, and yes — theft, if it exists.

That’s why it’s the real number.

If your wet GP is 60%, you know that for every pound you sell, you’re left with 60 pence of profit before you pay the staff or the rent. If it drops to 58%, something has changed. You don’t know if it’s pour cost, wastage, or both. But you know you need to investigate.

GP percentage also lets you compare performance across different lines and categories. Your draught lager might be 62% GP. Your cask ales might be 68% GP. Your spirits might be 59% GP. Now you know where to look first if something goes wrong.

Most pubs that move from a messy spreadsheet to a disciplined count routine — weighing open spirit bottles, dipping every cask, reconciling against till data the same day — claw back 1–2 GP points within a couple of months. That’s £2,000 to £5,000 a year on a typical pub wet sales figure.

A 1% stock loss on wet sales quietly costs a typical pub between £3,000 and £5,000 a year. A proper weekly line check catches it.

The Hidden Loss That Neither Metric Catches

Here’s the uncomfortable truth: most stock ‘theft’ is actually measurement error and forgotten wastage.

Spirits hide losses in over-pouring. A free-poured 25ml measure is often 32–35ml in reality. Do that 200 times a week, and you’ve given away 1.5 kegs a month. Your pour cost might look fine because your till says you sold it. Your GP percentage drops, but no one can point to where it went.

Draught hides it in poor cellar temperature and bad line cleaning waste. A cask that sits in a 18-degree cellar instead of 12 degrees carbonates faster, goes off sooner, and you dump the last 10 litres. Your till says you sold the first 110 litres. Your stock count says you should have 150 litres. The 40-litre gap is “waste” — it doesn’t show up in pour cost or GP until you physically count.

Spirits sit on the shelf. A bottle goes cloudy or the seal breaks. You throw it out three weeks later. By then, you’ve already sold £100 against its cost. That partial loss is invisible to EPOS.

The most effective way to catch hidden stock loss is to weigh open spirit bottles, dip every cask and partial keg, and reconcile against till data the same day every week. Not monthly. Not quarterly. Weekly. Variance patterns emerge fast when you’re disciplined.

I use a simple dipstick for kegs, a set of scales for spirits, and a physical note of what the till says we sold. Takes 20 minutes on a quiet Tuesday morning. Within a fortnight, I had a number I could trust. The spreadsheet I was using before? It was guesswork.

How to Track Both Properly (Without Wasting Time)

You need both metrics, but for different reasons. Pour cost tells you whether your supplier and buying strategy are working. GP percentage tells you whether your operation is working.

Here’s the system that works:

• Weekly physical count: Dip all casks and kegs. Weigh open spirit bottles. Record the data the same day.
• Till reconciliation: Pull your EPOS report for the same week. Compare what you counted to what the till says you sold.
• Calculate variance: Difference between counted stock and till data divided by till sales = actual stock loss percentage.
• Track by line: Don’t calculate one headline figure. Calculate wet GP by line — draught lager, cask ales, spirits, soft drinks, wine. The problem is almost always in one category.
• Set a trigger: If any line falls below its normal range two weeks in a row, investigate. Not panic. Investigate.

The StockTap pub stock app automates the recording and variance calculation. You still do the physical count — no app can do that — but you’re not then wrestling with a spreadsheet trying to reconcile numbers from three weeks ago when you can barely remember the numbers from yesterday.

Most spreadsheets fail because the data entry is a chore. SmartPubTools built StockTap because the founder — a working pub landlord — got fed up with the same problem. You count, you enter, the app does the maths and tells you whether anything has changed week-on-week.

Which Metric Should You Action First?

If your pour cost is above your pubco target and your GP percentage is below your normal range: you have a buying problem. Talk to your rep. Renegotiate, switch brands, adjust your mix.

If your pour cost is at or below target but your GP percentage is falling: you have an operational loss problem. Not buying. Loss. Check your cellar temperature, your line cleaning, your pour consistency, and your stock record accuracy.

If both are healthy: you’re doing the right things. Keep doing them. Track weekly so you catch the early warning signal before it becomes a crisis.

The number that actually matters is wet GP by line, not a single headline stock figure. Spirits hide losses in over-pouring (a free-poured 25ml is often 32–35ml). Draught hides it in poor cellar temperature and bad line cleaning waste. Most stock ‘loss’ is measurement error and forgotten wastage.

Weigh open spirit bottles, dip every cask and partial keg, and reconcile against till data the same day. Not because you think you’re being robbed. Because precision is the only way to know whether the pub is actually working.