How to pour a pint: the perfect pour step by step, the Guinness two-part pour, and what a bad pour costs a pub

How to pour a pint: take a clean, cold, dry glass, hold it at 45 degrees under the tap, open the tap fully in one movement and let the beer run down the side. At about halfway, bring the glass upright and pour into the middle so the head builds, then close the tap as the head reaches the rim. However big the head, the pint has to be at least 95% liquid.

That's the whole thing, and most of page one of Google says the same, because most of page one is breweries telling you how to pour their beer at home, or American sites talking in ounces. What none of them cover is the bit a pub cares about: what a bad pour costs over a week, and how the pour you teach shows up on your stocktake. So this is the bar version, with the sums.

The pour, step by step (lager, keg ale, cider)

1. Glass first. Clean, cold and dry, and the branded glass if you've got it. A glass straight out of the washer is hot and will fob the first inch of the pint. Hold it by the base, never the rim.
2. Tilt it to 45 degrees. Diageo's bar academy and Beavertown both start here. The nozzle sits close to the inside of the glass but doesn't touch it, and it never sits in the beer.
3. Open the tap fully, in one go. Diageo says open it fully. A half-open tap is one of the easiest ways to make fob, because the beer breaks up on the way through.
4. Straighten at halfway. Beavertown's guide: when the beer is about halfway up, bring the glass upright and pour into the centre. Less tilt early gives you more head, more tilt gives you less.
5. Close the tap cleanly at the rim. Shut it fully as the head reaches the top. Don't let the pint run over into the drip tray to knock the head off. That's beer you've paid for.
6. Serve it the right way round. Logo facing the customer, held by the base, on a dry surface.

If it's coming out fobby whatever you do, it's not the pour. It's temperature, gas or the line, and my beer fobbing guide has a table that finds the fault from where the fob shows up.

How big should the head be? The 95% rule

The industry guidance, from the BBPA and repeated by Cask Marque, is that a pint served with a head must be at least 95% liquid, and a customer who asks for a top-up should be served with good grace and never refused. 95% of a pint is 540ml, so the head can take up to 28ml of a brim-measure glass. In a lined glass, the line is the pint and the head sits above it, so you're pouring 100% liquid.

For a lager that means a head of about a finger, not a glass of foam. For Guinness, Diageo's own figure is 12 to 18mm. The legal side of short measures, lined glasses and the Weights and Measures rules is in the drink measures law guide.

Here's the bit nobody connects. The head is beer that never left the keg as liquid, so the size of the head you pour changes how many pints a keg gives you:

Pints from a 50 litre keg by how much of each pint is liquid (my arithmetic, 568ml pint, no other waste)

Liquid in each pint	Liquid per pint	Pints from a 50L keg	Versus full liquid
100% (lined glass)	568ml	88.0
97.5%	554ml	90.3	+2.3 pints
95% (the guidance minimum)	540ml	92.6	+4.6 pints

So a pub pouring a proper head in brim glasses should see draught running slightly into surplus on a stocktake, before waste. If yours is level or down, the head is hiding a loss somewhere else. I go through what a normal result looks like in acceptable stocktake variance and how many pints are in a keg.

The Guinness two-part pour

Diageo's own steps for draught Guinness, which is what the person asking for it expects:

1. A cool, clean, branded glass, held at 45 degrees. Open the tap fully.
2. Bring the glass upright as it fills and close the tap when the beer reaches the top of the harp.
3. Let it settle until the whole pint is one colour. Diageo says about 90 seconds.
4. Top it up by pushing the tap handle away from you until the head sits just proud of the rim, 12 to 18mm deep.
5. Serve with the logo facing the customer. Diageo gives 3 to 8°C as the serving temperature outside the US.

The settle is the bit busy bars skip, and it's the bit people notice. Pour the first half, serve the next customer, come back. What a pint of Guinness costs you and what to charge is in the Guinness pint cost guide.

Pouring cask from a handpull

Cask is different because the beer is alive and you're the pump. Timothy Taylor’s guidance is to test the beer at the cask and at the pump before every session, so the first pull of the day goes in a sample glass, not a customer's. Adnams says don't pump the beer engine rapidly, because it causes fobbing and waste. Long, steady, full pulls. Whether you use a sparkler is a question for the brewer, not the bar staff, because some beers are built for it and some aren't. If the cask itself isn't right, nothing at the pump fixes it, and how to tap a cask goes through getting it right in the cellar.

Is the glass beer-clean? Three 30-second tests

A greasy glass kills the head and leaves bubbles clinging to the sides. The Colorado Brewers Guild's glass guide gives three checks you can do at the bar:

Beer-clean glass tests (Colorado Brewers Guild)

Test	How	Clean	Dirty
Sheeting	Fill with water, tip it out	Water sheets off evenly	Water breaks into droplets or webs
Salt	Sprinkle salt inside a wet glass	Salt coats it evenly	Bare patches where the salt won't stick
Lacing	Pour a beer, drink or tip some, let the foam settle	Foam leaves parallel rings	Random pattern or none, bubbles stuck to the side

The usual causes, from the same guide: grease or detergent left on the glass, food plates or anything greasy going through the glass washer, and drying glasses with a bar towel. Let them air dry. Glass breakage and theft costs are their own leak, and I worked those out in what glass breakage and theft cost a pub.

What a bad pour costs

The pour losses that matter aren't the dramatic ones. They're the little bit that goes in the drip tray every time: running the tap to clear the head, a slop over the side, a pint poured and topped twice. Here's what that adds up to on a pub selling 800 pints of draught a week, at about £2 a pint cost:

Cost of a small loss on every pint, 800 draught pints a week, about £2 a pint cost (my arithmetic)

Lost per pint	Pints lost a week	Cost a week	Cost a year
10ml (a splash)	14	£28	£1,465
25ml (a slop)	35	£70	£3,662
50ml (run off the head)	70	£141	£7,324

None of that is anyone being dishonest. It's how people were shown to pour, usually on a busy Friday by whoever was free. Fix it with ten minutes of showing, not a telling off. I wrote up the training side in how to train bar staff and the pour side in what pouring habits cost your margin.

The test nobody does: pour into a measuring jug

Every pub has a view on its head size. Hardly any have measured it. So once, on a quiet afternoon, get everyone who works the bar to pour a pint of your best-selling lager the way they normally do. Let each one settle, then tip the liquid into a measuring jug and write the number down.

You'll get a spread. Somebody's pouring 555ml, somebody's pouring 520ml and somebody's pouring 568ml with half of it on the drip tray. Agree the house pour, show it once, and use that figure when you read your keg yields at the next stocktake. If your house pour is 97.5% liquid, a 50 litre keg should be giving you about 90 pints, and that's the number to hold your stocktake against, not 88. It costs nothing, takes half an hour, and the customer under 95% gets their top-up without having to ask.

Common questions

How do you pour a pint properly?

Use a clean, cold, dry glass held at 45 degrees, open the tap fully in one movement, bring the glass upright at about halfway and pour into the centre to build the head, then close the tap as the head reaches the rim.

How much head should a pint have?

Industry guidance from the BBPA, repeated by Cask Marque, is that a pint served with a head must be at least 95% liquid, so the head can take up to about 28ml of a brim-measure pint glass. For Guinness, Diageo says 12 to 18mm.

Can a customer ask for a top-up?

Yes. The BBPA and Cask Marque guidance says a request to top up a pint should never be refused.

How long does it take to pour a Guinness?

Diageo says pour to the top of the harp, let it settle for about 90 seconds until it is one colour, then top it up until the head sits just proud of the rim.

Why does my pint keep fobbing?

If the pour is right, fobbing is usually temperature, gas or the line: a cellar over 13°C, a struggling cooler, a keg on too soon or too long, gas left on overnight, a dirty line or a hot glass.

What is a beer-clean glass?

A glass with no grease or detergent left on it. Water sheets off it evenly, salt coats it evenly when wet, and beer foam leaves parallel rings as you drink.