The standard advice is that kegging costs more to start and saves money afterwards, so it pays for itself once you have brewed enough. The first half is true. The second half is not, and it is easy to check: at the prices this site's cost calculator uses, packaging a batch costs $1.89 in bottles and $1.90 in a keg. Kegging is a penny dearer.
How each one actually carbonates the beer
They get to the same place by different routes, and the difference explains most of the trade-offs below.
Bottling is biological. You stir a measured dose of sugar into the finished beer, fill and cap, and the yeast still in suspension eats it and produces CO₂ that has nowhere to go but into solution. Two to three weeks warm and the beer is carbonated. The dose is the whole game — our priming sugar calculator works it out from your volume, style and the warmest temperature the beer has seen since fermentation, which is the input most charts get wrong.
Kegging is mechanical. You transfer the beer into a sealed vessel and apply CO₂ from a cylinder at a pressure chosen so the beer absorbs exactly the carbonation you want, then serve at that same pressure. No yeast, no sugar, nothing to wait for beyond the gas dissolving — a day or two if you carbonate cold and patiently, faster if you are willing to shake the keg. You can also prime a keg with sugar like a big bottle, which some people do to avoid buying a cylinder at first.
What you actually have to buy
To bottle: a capper (a $15 wing capper works forever), a bag of crown caps, a bottling bucket with a tap, and a bottling wand. Call it $40–60 all in. Bottles themselves are free if you drink commercial beer and keep the pry-off ones — never twist-offs, which do not re-seal.
To keg: a corny keg ($80–120 new, less used), a CO₂ regulator ($60–80), a five-pound cylinder ($80–100 filled), gas and liquid disconnects with line, and somewhere cold to keep it. That last item is the one that decides the budget: a spare fridge you already own costs nothing and a purpose-built kegerator costs more than everything else combined.
And a running cost neither side's marketing mentions: a keg system needs cleaning too. Lines want flushing between batches, the keg needs stripping and its posts and poppets cleaning properly, and neglecting either is exactly how the lasting infections in our off-flavors guide get established. It is far less work than washing 50 bottles — but it is not the zero the time table implies, and it is work you cannot skip.
What each one actually costs per batch
Bottling consumes priming sugar and crown caps: 130 g of sugar and 50 caps for the default batch. Kegging consumes CO₂ — 172 g of it to carbonate the keg, push the beer out over its life, and purge the vessel before filling. Neither is expensive and neither is meaningfully cheaper:
| Bottling | Kegging | |
|---|---|---|
| Consumables per batch | $1.89 — sugar and 50 caps | $1.90 — 172 g CO₂ |
| Beer that reaches the glass | 18.0 L | 18.4 L |
| Packaging-day labor | 1.5–3 hours | 15–30 minutes |
| Ready to drink | 2–3 weeks | 1–2 days forced, or the same 2 weeks primed |
| Up-front gear | $40–120 | $150–400, plus cold space |
Consumables and volumes from this site's engine at the cost calculator's default prices — a $25 five-pound CO₂ cylinder, $3/kg sugar, 3¢ caps. Time and gear ranges as published by learningtohomebrew's comparison, which is the only one that quotes both.
The one genuine per-batch saving is easy to miss: a keg does not have a bottling bucket to leave beer in. Our packaging ledger puts that at 450 mL a batch — just under a pint, or about $2.38 of beer you would otherwise pour down the drain.
So when does kegging pay for itself?
Take the whole per-batch advantage — the penny you lose on gas, plus the $2.38 of beer you keep — and divide the up-front cost by it:
| Kegging setup | Pays back after | At six batches a year |
|---|---|---|
| $200 | 84 batches | 14 years |
| $350 | 147 batches | 25 years |
| $500 | 211 batches | 35 years |
| $800 | 337 batches | 56 years |
Up-front cost divided by $2.37 of per-batch advantage, computed from this site's engine. On the consumables alone, ignoring the beer saved, it never pays back at all.
It does not pay for itself. A $350 setup takes 147 batches, which at six brews a year is 25 years — longer than most people stay in the hobby, and that is the optimistic version that counts the saved beer at retail. learningtohomebrew's comparison is right to say "there is no universal N" and to warn against treating "kegging pays off after 8 to 12 batches" as a fact. The N depends on your prices, and for anything like normal prices it is not a number that should influence your decision.
What kegging actually buys
Time, and a lot of it. Bottling a batch is 50 separate fills, caps and a capper, plus washing and sanitizing 50 bottles first — the part nobody counts. Kegging is one vessel: sanitize, transfer, set the regulator, walk away.
| Batches a year | Hours bottling | Hours kegging | Given back | $350 over 3 years |
|---|---|---|---|---|
| 4 | 8 h | 1.3 h | 7 h/yr | $18/hour |
| 6 | 12 h | 2.0 h | 10 h/yr | $12/hour |
| 12 | 24 h | 4.0 h | 20 h/yr | $6/hour |
Two hours a batch to bottle and twenty minutes to keg, inside the ranges published by the comparisons. The last column is the up-front cost divided by the hours it gives back over three years.
At 6 batches a year, bottling is 12 hours of your weekends and kegging gives 10 of them back. Spread $350 of gear over three years and you are buying your own Saturday afternoons at about $12 an hour. That is a genuinely good deal for most people — but it is a convenience purchase, not an investment, and the pages that sell it as savings are doing you no favors.
The things money does not measure
Kegging wins on carbonation control. You set a pressure and the beer holds it — our keg carbonation calculator gives the psi for a temperature and a style, and you can change your mind afterwards. A bottled batch is committed the moment you add the sugar, and getting that wrong is the one packaging mistake that can hurt you: see the bottle-pressure numbers in our stuck fermentation guide.
Kegging is also gentler on the beer. One quiet transfer into a purged vessel beats 50 individual fills for oxygen pickup, and oxidation is the fault with no cure — the purge table in our off-flavors guide shows what a couple of CO₂ cycles are worth.
Bottles win on everything portable. You cannot take a keg to a party, post one to a competition, or leave three in a friend's fridge. They stack in a cupboard rather than occupying a refrigerator, they cost nothing if you drink commercial beer, and a bottled batch can be split across a dozen occasions over a year without a CO₂ line following it around. For cellaring a strong beer, bottles are simply the right answer.
Most people end up doing both
The common landing point is kegging the batch and bottling a few off the keg for competitions and gifts, using a counter-pressure filler or a beer gun. That costs another $40–100 and takes the portability argument off the table, which is why so many brewers who "switched to kegging" still have bottles in the cupboard.
If you are deciding today: bottle while you are still finding out whether you will keep brewing, because $40 of gear and an afternoon is the cheapest way to package beer that has ever existed. Switch when bottling day starts to feel like the reason you are not brewing — that is the signal the 10 hours are worth $350 to you, and it is a much better reason than a payback period that never arrives. Put your own prices into the batch cost calculator and it will do this arithmetic for your setup rather than ours.