The Good brew

Home brewing vs buying kombucha: the real cost breakdown

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You’ve been getting through two or three bottles of kombucha a week for the past six months. The fridge is permanently a third full of empties. The grocery bill has crept up enough that you’ve started running the numbers.

Two bottles a week at $4 to $5 each. Multiply it out and the figure is not small.

So you’ve started wondering: is it cheaper to make kombucha at home?

We’ve brewed kombucha out of our Brunswick brewery since 2007, and we sell both bottled kombucha and a complete homebrew kit. So the honest answer matters more to us than the easy answer. Home brewing is cheaper per litre. Often dramatically so. The upfront kit isn’t free, though, and the kit only pays off if you drink the kombucha you make.

This article shows the actual numbers. Costs of buying bottled, costs of brewing at home, where the break-even point sits, and which path makes sense depending on how much kombucha you drink.

Option	Upfront cost	Cost per litre	Break-even
Good Brew 330ml single bottle	None	$13.64	n/a
Good Brew case (24 x 330ml, 7.92L)	$100	$12.63	n/a
Good Brew Gut Starter subscription (4.5L/month)	None	approx. $9.17	n/a
Supermarket kombucha (mid-range)	None	$11 to $15	n/a
Home brew with Good Brew COMPLETE Kit	$74.95	$1 to $3	7 to 10 litres of brew

What does a kombucha brew kit cost?

A kombucha brew kit is a one-off purchase that bundles the equipment, the live culture, and the starting ingredients to ferment your first batches.

The Good Brew COMPLETE Homebrew Kombucha Kit is $74.95 and includes everything you need except water. What’s inside:

SCOBY ($19.95 value): the live culture that does the fermenting.

Brew Bible: full step-by-step instructions.

8L glass fermenter ($44.95 value): with a food-grade tap so you can pour without disturbing the SCOBY.

100g organic green and oolong tea blend ($11.95 value): the same certified organic blend we use in our commercial brews.

100g organic raw Brazilian sugar: from regenerative farming.

Fermentation cloth ($3.85 value): breathable cover that keeps fruit flies out and lets the SCOBY breathe.

80-strip pH testing booklet ($8.80 value): for checking your brew is fermenting in the right range.

Bought separately, those pieces add up to $89.50. The kit saves you $14.55, about 16% off individual purchases.

If you already own a large glass jar and fermentation cloth, the 220ml SCOBY starter kit at $19.95 is the minimum entry point. For most people starting out, the COMPLETE Kit is the simpler choice. The fermenter is sized to the recipe, and the tap matters more than people expect.

What does each litre of home brew cost?

After the kit, ongoing cost comes down to tea, sugar and water. Good Brew’s recipe is 5g of tea and 50g of sugar per litre of finished kombucha.

Organic raw sugar runs $5 to $10 per kilo at supermarkets. For 50g per litre, that’s $0.25 to $0.50.

Organic green tea or an oolong blend runs $6 to $15 per 100g at most Australian retailers. For 5g per litre, that’s $0.30 to $0.75.

Filtered tap water is essentially free. Brewers using spring or mineral water pay an extra $0.50 to $2 per litre.

Total ingredient cost lands at roughly $1 per litre with supermarket organic ingredients and tap water, or up to $3 per litre with premium ingredients and bottled spring water.

The SCOBY is reusable. Out of the fridge it stays active for at least six months. In the fridge between brews it can last over two years. The $19.95 starter cost spreads across dozens of litres, so its per-litre share is negligible after the first few batches.

What does it cost to buy kombucha instead?

Three buying options, with three different cost profiles.

Good Brew single bottles and cases

A 330ml bottle is $4.50, which works out to $13.64 per litre. A case of 24 bottles (7.92L) is $100, or $12.63 per litre. The case is better single-purchase value, but you’re still paying mostly for bottles and the work that goes into a small-batch commercial brew.

Good Brew subscriptions

No lock-in. 25% off the first two months. From month three a free 750ml gift bottle each delivery. The entry-level Gut Starter at $41.25 per month gets you 4.5L (six 750ml bottles), or roughly $9.17 per litre. After the introductory months it settles around $9 per litre. For anyone drinking more than a litre a week the subscription is meaningfully cheaper than buying singles.

Supermarket kombucha

Major brands like Remedy and Mojo sit at $4 to $5 per 330ml bottle at Coles and Woolworths. That’s roughly $11 to $15 per litre. Close to Good Brew singles per litre, but the products are different. A lot of supermarket kombucha is mass-produced. Some is pasteurised, which kills the live cultures that make kombucha what it is. Others use erythritol and stevia in place of sugar. Read the label if those things matter to you.

The break-even point: when does the kit pay for itself?

The $74.95 kit pays for itself in 7 to 10 litres of home brew, depending on what you were buying before.

If you currently buy Good Brew singles or supermarket kombucha: roughly 7 to 8 litres.

If you currently subscribe to Good Brew: roughly 10 to 12 litres.

That’s one to two full runs in the 8L fermenter the kit includes. After break-even, your ongoing kombucha cost drops from $9 to $14 per litre to closer to $2.

A practical example. A household drinking 2L a week hits break-even somewhere between weeks four and six. From there, every batch is largely free compared to what they were spending.

When buying makes more sense than brewing

The kit isn’t the right call for everyone. Buying is the better answer if:

You want a consistent commercial product. Home brew varies a little from batch to batch. The same recipe in a slightly warmer kitchen ferments faster and tastes different. If you want the same flavour and fizz every time, bottled is the answer.

You don’t have the bench space. The 8L fermenter is roughly 31cm tall and 19cm wide. That’s a meaningful footprint to leave out for two weeks at a time.

You don’t want a fermentation project. Brewing involves temperature awareness, second fermentation if you want carbonation, and the odd dud batch when the SCOBY needs attention.

You travel often. A brew on a two-week cycle doesn’t pause well when you’re away for a fortnight.

You drink less than a litre a week. Break-even comes too slowly to bother. A 6 pack or a Gut Starter subscription costs less than the kit and gives you the kombucha now.

When brewing pays off

The other side. Genuine reasons home brewing wins:

You drink more than 2 litres a week. The maths gets silly quickly. At $1 to $2 per litre for home brew, against $9 to $14 per litre for any commercial option, the kit pays for itself in a month.

You like flavour experimentation. Second fermentation with fruit, ginger, herbs and spices is where home brewing gets fun. Good Brew sells $11 infusion packs if you want a starting point.

You want raw, alive kombucha and full control of the ingredients. Home brew is raw by definition. You choose the tea, sugar, water and ferment time. There’s no commercial shortcut that gets close to that.

You’re already shopping organic. Buying organic tea and sugar by the kilo is cheaper than paying for someone else to do the same shopping.

You enjoy the process. Many regular home brewers aren’t doing it just for the savings. It’s a quiet two-week rhythm of doing something useful with tea and time.

A hybrid approach worth considering

Many regular kombucha drinkers don’t stay purely in one camp. The pattern we see in the tap room at 54 Hope St is closer to a split: home brew for everyday drinking on a simple base recipe, a Good Brew subscription for variety and the bottles you reach for at the end of a long week, and a 6 pack on hand for guests.

That split lands cheaper than full subscription and easier than brewing every litre you drink.

If you’re ready to commit to brewing, the COMPLETE Homebrew Kit at $74.95 is the cleanest start. If you want to skill up first, our brewing workshop runs the last Thursday of every month at the Brunswick brewery for $53.95. You work hands-on with a SCOBY and a fermenter, and you walk out knowing the steps. If you’re not ready to commit at all, a 6 pack of 330ml bottles or a Gut Starter subscription will keep real, raw kombucha in the fridge while you decide.