Draught Beer Stocktaking Guide

Last updated: 29 June 2026

Most pubs lose money on draught without realising it—not through outright theft, but through measurement error, temperature drift, and forgotten wastage that your till never sees. After 15 years running a Marston’s pub, I can tell you that a 1% stock loss on wet sales quietly costs a typical pub £3,000–£5,000 a year, and draught beer is where it happens first. The problem isn’t that you’re being robbed; it’s that you don’t know what you actually have. A proper weekly draught beer stocktaking routine catches this fast. This guide walks you through exactly how to count what you’ve got, spot where losses hide, and build a system that works in a busy pub without adding hours to your week.

Why Standard Stocktakes Miss Draught Loss

Most pubs run a full stocktake once a month or quarterly. You count bottles, count casks, write it down, and call it done. The problem is that by the time you’ve finished counting, you’ve lost sight of what happened during the month. A cask that’s been sitting in a warm cellar for three weeks doesn’t tell you anything from a snapshot count—you’ve already lost litres through evaporation and CO₂ loss. The number that actually matters is wet GP by line, not a single headline stock figure.

Draught beer hides losses in three places: over-pouring (a free-poured 25ml is often 32–35ml when measured), cellar temperature swings, and line cleaning waste. A monthly count catches the headline number but misses the pattern. A weekly line check tells you exactly which line is bleeding profit and when the problem started.

I was running stock on a tangle of spreadsheets and still losing track of partial kegs and spirit measures. I built a simple count routine around a dipstick and a set of scales, and the weekly variance went from guesswork to a number I could trust within a fortnight. That’s when I saw the real story: one line was consistently under by 5 litres a week—not because of theft, but because the line temperature was running 2°C too warm.

The Equipment You Actually Need

You don’t need gadgets. You need three things that cost under £50 total.

• A dipstick. Measure the depth of beer in every cask and partial keg. Record it against the volume graduation on the cask. Takes 30 seconds per cask. A wooden dipstick costs £8.
• A set of scales. If you’re running spirits alongside draught, weigh open bottles the same day you count. A 15kg digital scale costs £30. Spirits hide losses in over-pouring; scales don’t lie.
• A temperature probe. A cheap digital probe (£12) tells you your cellar is holding 10°C or 14°C. CO₂ loss accelerates sharply above 12°C. You need to know.

A notebook or a simple spreadsheet is fine for recording. Some pubs have moved to a tablet or phone app, and if that works for you, fine—but the discipline matters more than the medium. Write down the date, time, cask ID, dipstick reading, and any notes (line disconnected, temperature, spillage). Do it the same time every week.

Don’t overthink the tools. I’ve seen licensees spend £500 on a fancy cellar management app and then abandon it after a week because it’s slower than writing it down. A StockTap pub stock app or a spreadsheet does the job if you use it consistently. The magic isn’t the tool; it’s the routine.

The Weekly Line Check Method

A weekly draught stocktake takes 15–20 minutes if you’re disciplined and know what you’re counting. Here’s the exact routine I use.

Step 1: Before Service on the Same Day Each Week

Pick a quiet time—Monday morning is ideal. You want the line to be at rest, not immediately after the busy weekend. Take a dipstick to every cask and partial keg in the cellar. Measure the depth. Write it down alongside the cask ID or line name. If you’ve got a barrel with a gauge glass on the side, use that instead—it’s faster and more accurate.

Step 2: Check the Line Temperature

Stick a temperature probe in the coldest part of the cellar. Draught beer should sit between 8°C and 12°C. If it’s creeping above 12°C, you’re losing CO₂ and the beer will taste flat or sour within a few days. If it’s below 8°C, you’re wasting energy and the beer won’t pour properly. Record the temperature.

Step 3: Note Any Spillage or Waste

If a line was disconnected for cleaning, if someone dropped a cask, if you vented a line because the pressure went wrong—write it down. This is crucial. Most “stock loss” is actually forgotten wastage that nobody recorded. When you reconcile later, you need to explain every litre that moved.

Step 4: Cross-Reference Against Till Data

At the end of the day, pull your EPOS report for pints sold by line. Compare it to your dipstick reading. If you sold 40 pints from a line and the cask dropped by 48 litres (accounting for a pint being 568ml), something’s wrong. You’ve either got a leak, the line is running too fast (over-pouring), or your till data is miscategorising a line. This is where you find the real problem.

Reconciling Draught Against Till Data

This is the step most pubs skip—and it’s the only one that matters. Reconciling your draught count against till data the same day tells you whether you made money.

Here’s the maths. Let’s say your lager line shows:

• Monday dipstick reading: 80 litres remaining in cask
• Friday dipstick reading: 35 litres remaining in cask
• Difference: 45 litres poured out
• EPOS shows: 82 pints sold (82 × 0.568L = 46.6 litres)

You’re roughly in line. A difference of 1–2 litres is normal (head on the beer, line filling, spillage). A difference of 5+ litres is a flag. It could mean:

• The till didn’t ring through free pints (staff training issue)
• The line is leaking or over-pouring (cellar/line issue)
• Your opening or closing dipstick reading was inaccurate

You won’t know which without digging. But you know that something happened. That’s progress.

The mistake most pubs make is running the reconciliation once a month. By then, you’ve got five weeks of variance stacked on top of each other, and you can’t trace the problem. A weekly reconciliation takes an extra 10 minutes on Friday, and you know immediately which line is drifting. If it’s the same line every week, you’ve got a systematic problem—not a one-off accident.

Temperature and Wastage—The Hidden Drains

Spirits hide losses in over-pouring; draught hides it in poor cellar temperature and bad line cleaning waste. If your cellar is running warm, you’re not just losing money on taste—you’re losing volume.

Beer is mostly water. Water evaporates. A cask sitting in a 14°C cellar for a week will lose more CO₂ than one in a 10°C cellar. The beer becomes flat, tastes off, and customers leave it half-full. You can’t sell it; you dump it. Your till says you poured it; your cask count says it left. The difference never gets explained.

Temperature management is a direct profit lever. If your cellar drifts 2–3°C warmer than it should, and you’ve got four casks on draught, you’re leaking 5–10 litres a week through evaporation and CO₂ loss alone. Over a year, that’s 260–520 litres—roughly 10–20 casks. At £80–100 per cask, that’s £800–2,000 in lost profit.

Line cleaning wastage is equally brutal. Every time you clean a draught line—which you should do weekly—you’ll lose 2–5 litres to flushing and re-filling the line. If you’ve got four lines and you’re cleaning them all at once, that’s 8–20 litres gone. Record it. Your stocktake will show a drop; your till won’t. If you don’t account for it, you’ll think you’ve got a leak.

Common Mistakes That Waste Your Time

Mistake 1: Running a stocktake without a plan for what to do with the data. You count everything, write it down, and then never look at it again. The data only matters if you’re going to act on it. Set aside 15 minutes on Friday to reconcile your weekly count against till data. If there’s a variance, investigate immediately. If there’s a pattern, fix it.

Mistake 2: Assuming your brewery stocktaker will catch the problem. A brewery stocktaker visits maybe once a quarter. They’re also working on behalf of the brewery, not you. Their job is to confirm the casks they’ve supplied are accounted for—not to find out where your profit went. You’re the one who needs to know, week by week.

Mistake 3: Using visual guessing instead of measurement. “That cask looks about three-quarters full” is worthless. A dipstick takes 30 seconds and tells you exactly what you’ve got. The difference between guessing and measuring is often 5–10 litres per cask per week. Over 50 weeks and four lines, that’s 1,000–2,000 litres of untraced loss.

Mistake 4: Mixing up line cleaning waste with stock loss. You cleaned a line yesterday and flushed 5 litres. Your cask count is down 5 litres. Your till shows no sales. This isn’t loss—it’s planned waste. If you don’t record it, you’ll spend hours trying to find a leak that doesn’t exist.

Mistake 5: Not using a system. A spreadsheet, a notebook, or SmartPubTools cellar tracking—pick one and stick with it. The consistency matters more than the tool. I’ve seen licensees jump between three different methods in a year and then wonder why they’ve got gaps in their data.