Cask Ale ABV and Beer Duty Bands Explained

Last updated: 29 June 2026

Most pub licensees never look at the ABV figure on a cask until the brewery’s invoiced them. By then it’s too late—the duty band is locked in, and it’s already eating into your margin. The difference between a 3.8% bitter and a 4.2% bitter can cost you £40–£60 per cask in duty alone, and if you’re not tracking which beers sit in which duty bands, you’re flying blind on one of your biggest cost levers.

I spent three years rotating cask ales through my cellar without understanding why some suppliers’ invoices looked different from others at the same volume. Turns out I was mixing duty bands without even realising it—which meant my GP per pint was wildly inconsistent, and I couldn’t price accurately because I didn’t know my true landed cost.

This article explains exactly how duty bands work, why ABV matters to your bottom line, and how to track cask ale duty so you know whether you’re making money or subsidising your customers’ pints.

How Beer Duty Bands Work in the UK

Beer duty in the UK is a tax levied per litre of beer sold, calculated according to the alcoholic strength (ABV) of the liquid in the container. The rate changes at set ABV thresholds, and the brewery calculates and pays the duty upfront—then passes it on to you in the invoice price. You don’t pay HMRC directly; the duty is already embedded in what you pay per cask.

This is important because it means your cost per cask is fixed the moment you order it. The duty band is determined at the point of production. You cannot negotiate it, move it to a different band, or apply for relief once you’ve received the cask.

The HM Revenue and Customs (HMRC) publishes duty rates annually and adjusts them for inflation. In 2026, there are five main duty bands for beer, each with a specific threshold in ABV percentage.

What most licensees don’t realise is that a brewery can produce the same beer—same recipe, same water, same hops—in two slightly different versions with different ABV targets, purely to hit a lower duty band. A 3.8% session bitter costs less duty per cask than a 4.2% version of the same ale, even though the flavour and shelf life are nearly identical. The brewery will often label these differently (Session, Classic, Reserve, etc.) to keep them distinct in your eyes. But for your cost tracking, you need to know which SKU sits in which band.

ABV Thresholds and Duty Rates in 2026

As of 2026, the UK beer duty system operates on five bands:

• 0.0% to 1.2% ABV: Zero duty (low-alcohol and alcohol-free beers)
• 1.2% to 2.8% ABV: Band A rate (the lowest duty-bearing band)
• 2.8% to 4.3% ABV: Band B rate (most session bitters and pale ales sit here)
• 4.3% to 6.9% ABV: Band C rate (standard strength and premium ales)
• Above 6.9% ABV: Band D rate (strong ales, barley wines, imperial stouts)

The actual pence-per-litre rates are adjusted by HMRC each March and are published on the HMRC beer duty guidance page. Rather than quote specific figures (which change annually), the key principle is this: each threshold represents a significant jump in cost per pint, and the jump becomes steeper as ABV rises.

For practical purposes: a cask at 4.2% ABV (Band C) will cost you roughly 30–40% more in duty per pint than a cask at 3.5% ABV (Band B). That difference is pure cost; you don’t get extra volume or flavour to offset it. So if you’re pricing both at £3.50 a pint, you’re actually making less GP on the stronger beer.

The critical insight is that ABV thresholds are hard boundaries. A beer at 4.29% ABV sits in Band B. Move it to 4.31% and it jumps to Band C. The brewery controls this, and they set it deliberately. Some suppliers will stock a 4.2% and a 4.1% version of the same ale specifically to give licensees a choice—often without highlighting the duty-band difference in their promotional material.

Why Cask Ale Duty Matters to Your GP

Here’s where this gets real: your gross profit per pint depends entirely on three things: the price you sell at, the volume you sell, and the cost you paid to the brewery. Duty is baked into that cost. If you don’t know the duty band of every cask in your cellar, you cannot calculate accurate GP by line.

A typical mid-range cask ale in Band C might cost you £85–£95 landed, depending on your supplier and discount. That same ale in Band B might cost £75–£82. If you’re buying blind—just “we’ll have a cask of that bitter”—you might be paying more than you think, and your GP math will be wrong.

Here’s a real example from my own pub: I was stocking a particular brew in two variants—one at 3.8% (Band B) and one at 4.1% (Band C). I was selling both at the same price because I didn’t bother checking ABV. The Band C version was costing me £8 more per cask in duty alone. Over a year, stocking two Band C casks a week instead of Band B, that’s over £800 in unnecessary duty cost. I was subsidising the stronger version without knowing it.

Most stock losses are not theft—they’re measurement error and forgotten wastage. But when you’re also mispricing beers across duty bands, you’re not just losing money on loss; you’re losing it on every pint sold.

The solution is simple: know the ABV of every cask you order. Check it before you order. Add it to your supplier order notes. When the cask arrives, verify it on the invoice. Then, when you do your StockTap pub stock app counts, record the duty band alongside the dip and wastage. That way, when you reconcile GP by line, you’re comparing apples to apples.

Tracking Cask ABV and Duty Across Your Cellar

The easiest way to track duty band liability is to make ABV part of your standard cellar record. When you receive a cask, the invoice tells you the ABV and the duty-inclusive price. Write both down.

For cask ales, I use a simple approach:

• On delivery, check the cask label and invoice for ABV. Note it in your cellar book or your counting system.
• Record the delivered cost and the duty band (A, B, C, or D).
• When you dip the cask or count partial kegs, you already know which duty band you’re tracking.
• When you sell the cask out, you reconcile the volume sold against the till and calculate GP for that specific line.

If you’re moving from spreadsheets to a structured cellar system, this is where things get concrete. A 1% stock loss on wet sales quietly costs a typical pub £3,000–£5,000 a year. But that’s just the loss figure. The bigger cost is that you don’t know whether the loss is happening on Band A beers (lower impact) or Band D strong ales (higher impact). Without knowing the duty band, you can’t even prioritise which lines to investigate first.

When I switched from a tangle of spreadsheets to a proper dipstick and scale routine, I started recording ABV at the same time as I recorded the dip. Within a fortnight, my weekly variance went from guesswork to a number I could trust. More importantly, I could see that my Pale Ale (Band C) was consistently short by 2–3 pints per week, while my Session Bitter (Band B) was bang on. That told me something was wrong with the pale ale line—either over-pouring, temperature, or cellar waste. Without tracking ABV alongside the dip, I would never have spotted the difference.

Common Duty Band Mistakes That Cost You Money

Mistake 1: Not checking the ABV when you order

You ring your supplier and say “send me a cask of the usual bitter.” Your supplier sends what they have in stock, which might be a slightly different version (or strength) than last week. You don’t notice. It arrives at a different price point, but you’re already pricing it based on last week’s margin assumption. By the time you notice the price is different, you’ve already sold the cask at the wrong margin.

Mistake 2: Mixing duty bands without reconciling the difference

You have three similar-looking ales on the bar—a session pale at 3.8%, a classic pale at 4.1%, and a reserve pale at 4.4%. They’re all under the “Pale Ale” category in your head, but they’re in three different duty bands. When you do your weekly stocktake, you lump them together as “pale ale wastage” without breaking down which specific SKU is costing you money.

Mistake 3: Assuming your brewery’s invoice is correct without verification

Most invoices are correct, but I’ve seen cases where a cask has been mislabelled at the brewery, or where the invoiced ABV doesn’t match the cask label. If you’re relying on the invoice alone and never checking the physical cask, you might be holding the wrong duty band liability in your records.

Mistake 4: Not accounting for duty liability in your cash position

This is subtle but important. When you pay for a cask, the cash has left your account. But the duty liability is already embedded in the price. If you’re analysing your cash position week-to-week without understanding duty, you might think you’ve had a good week on sales when actually you’ve just stocked more high-duty beers, which cost more cash upfront but don’t necessarily sell faster.

Duty Liability and Your Weekly Numbers

At the end of each week, your cellar should tell you four things: opening stock, purchases, sales (from the till), and closing stock. The duty band is part of the opening and closing stock valuation. If you don’t know the ABV of every cask you’re holding, your closing stock figure is unreliable.

Here’s the operator insight most systems miss: 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, and most stock ‘theft’ is actually measurement error and forgotten wastage. You need to weigh open spirit bottles, dip every cask and partial keg, and reconcile against till data the same day.

When you do this, duty band becomes part of your decision-making. If a high-duty cask (Band C or D) is showing consistent short variance, the cost of fixing it (line cleaning, temperature adjustment, staff retraining on pour size) is worth the investment because you’re protecting a higher-margin line. If a low-duty cask (Band A or B) is showing small variance, you might tolerate it as a cost of doing business.

This is why I built my own counting routine around duty bands early on. I wasn’t trying to be fancy; I just wanted to know which of my beers was actually costing me money. Once I could answer that question accurately—linking ABV, duty band, cost, sale price, and actual variance into one weekly number—my GP went up, not because I suddenly started selling more, but because I stopped subsidising the wrong beers.

For most pubs that move from a messy spreadsheet to a disciplined count routine, a 1–2 GP point recovery is normal within a couple of months. That’s not magic. It’s just the effect of knowing your actual costs and reconciling them against your actual sales.

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