How to Bottle and Carbonate Your Homebrew

Bottling is the final step between a fermenter full of flat beer and a fridge full of cold, carbonated homebrew. It's simple, but it's also where a little care pays off — good technique here is the difference between perfectly fizzy pints and flat beer or over-carbonated gushers. Here's exactly how it works.

How bottle carbonation works

Your beer isn't carbonated by a machine — it carbonates itself. When you add a small, measured dose of "priming sugar" at bottling and seal the cap, the yeast still suspended in the beer eats that sugar and produces carbon dioxide. With nowhere to escape, the CO₂ dissolves into the beer, giving you natural carbonation right in the bottle. This is called bottle conditioning.

What you'll need

• Around fifty clean, sanitized 12 oz bottles per 5-gallon batch (pry-off, not twist-off)
• Bottle caps and a capper (a wing capper is inexpensive and lasts for years)
• Priming sugar — corn sugar (dextrose) is standard; plain table sugar works too
• A bottling bucket with a spigot, and ideally a bottling wand
• No-rinse sanitizer for everything the beer will touch

How much priming sugar?

For a standard 5-gallon batch of ale, about 5 oz (roughly 3/4 cup) of corn sugar gives a pleasant, medium carbonation. Table sugar is a little more concentrated, so use slightly less — around 4 oz. The single most important rule: measure it. Guessing high is how you get gushers and, in extreme cases, exploding bottles.

Step by step

1. Confirm fermentation is finished. The airlock should be quiet, and if you have a hydrometer, the gravity should be stable over a few days. Bottling too early is the classic cause of over-carbonation.
2. Sanitize everything. Bottles, caps, bottling bucket, spigot, wand, and your siphon. This is non-negotiable at every step that touches finished beer.
3. Make a priming solution. Boil your measured priming sugar in about 2 cups of water for a few minutes, then let it cool slightly. Add it to the empty, sanitized bottling bucket.
4. Rack the beer onto the sugar. Gently siphon the beer from the fermenter into the bottling bucket, leaving the sediment (trub) behind. The gentle swirl mixes the priming solution evenly — but pour gently and avoid splashing, since oxygen at this stage causes stale, cardboard flavors.
5. Fill the bottles. Use the spigot and bottling wand to fill each bottle, leaving about an inch of headspace at the top. Pressing the wand against the bottom starts the flow; lifting it stops it.
6. Cap and store. Cap each bottle firmly, then store them upright somewhere dark at room temperature (around 68–72°F).

How long does it take?

Give the bottles about two weeks at room temperature to carbonate — the yeast needs warmth to do its work, so don't refrigerate them yet. After two weeks, chill one and test it. If it's carbonated to your liking, move the rest to the fridge; if it's still a little flat, give them another few days to a week. Bigger, stronger beers and stouts often take longer.

Troubleshooting

• Flat beer: usually too little priming sugar, storing bottles somewhere too cold, or not waiting long enough. Move them back to room temperature and give it more time before giving up.
• Over-carbonated or gushing: typically bottling before fermentation finished, too much priming sugar, or an infection. Refrigerate the bottles to slow things down and open them carefully (over a sink).
• Sediment in the bottle: totally normal with bottle conditioning. That thin layer of yeast at the bottom is harmless — just pour gently and leave the last half-inch behind.

What about kegging?

Once you've bottled a few batches, kegging becomes tempting — you force-carbonate with CO₂ and pour from a tap instead of filling fifty bottles by hand. It's a bigger upfront investment, but it ends bottling day. Plenty of brewers keg most of their beer and bottle just a few for sharing. If a keezer or kegerator is in your future, you'll see one on our builds page.

That's everything you need to carbonate great beer without any special equipment. Next up: brew another batch from the recipes page, or brush up on what to avoid in our beginner mistakes guide.