Why Your Sourdough Isn't Rising (and How to Fix It)

You mixed the dough, followed the recipe, and waited. Hours later, the dough looks almost exactly like it did when you put it in the container. No rise. No bubbles. Just a lump of flour and water staring back at you.

This is one of the most common frustrations in sourdough baking, and it almost always has a fixable cause. The hard part is that “sourdough not rising” isn’t a single problem — it’s a symptom that can come from several different places. A starter that isn’t ready. A kitchen that’s too cold. Dough that needs more time. Ratios that got thrown off somewhere.

Working through these systematically isn’t complicated, but you do have to check the right things. Here’s how to do that.

Start Here: Is Your Starter Actually Ready?

This is the cause of most failed rises, and it’s the right place to start.

A sourdough starter that isn’t active enough won’t leaven bread. It doesn’t matter how well you shaped the dough or how warm your kitchen is — if the starter can’t produce enough gas, the dough won’t rise. This is true whether you’re brand new to sourdough or you’ve been baking for a year and something recently changed.

How to check: Feed your starter and watch it over the next 4 to 12 hours. A healthy, active starter should roughly double in volume (some go higher), show consistent bubbling throughout, and have a domed or slightly peaked top at maximum rise. If it’s barely moving, it’s not ready to leaven bread.

The float test — dropping a small spoonful of starter into water to see if it floats — is a rough indicator. Floating suggests enough gas production to potentially leaven dough. But it’s not definitive. A starter can pass the float test and still be too sluggish to produce a good rise. The volume doubling and dome are more reliable signals.

Common starter problems that kill the rise:

Not fed recently enough. A starter that was last fed two or three days ago has likely burned through its food and is past peak activity. Feed it and give it time to come back.
Wrong feeding ratio. Feeding very small amounts of flour doesn’t give the starter enough food to build strength. A 1:5:5 or 1:10:10 (starter:water:flour) ratio produces a more vigorous starter than a 1:1:1.
Wrong flour. All-purpose works. Whole wheat and rye tend to produce more active starters because of the extra nutrients. Bleached flour can inhibit activity. If you recently switched flours and your starter slowed down, that may be why.
Temperature too cold. Starter ferments slowly in a cold kitchen. At 65°F (18°C), a starter that normally peaks in 6 hours might take 10 or 12. It’s not dead — it’s just slow.
Chlorinated water. Chlorine in tap water can suppress fermentation. If you’ve been using tap water, try filtered or let tap water sit uncovered overnight to off-gas.

The Starter Feeding Calculator can help you find a feeding ratio and schedule that builds consistent activity. If your starter has been unreliable, spending a week on a regular feeding schedule before baking again is usually the fastest path to fixing the problem.

Second: Temperature

If your starter is active but your dough still isn’t rising, temperature is the next variable to examine.

Yeast activity drops significantly as temperature falls. A dough that takes 5 hours to bulk ferment at 76°F (24°C) might take 9 or 10 hours at 68°F (20°C). If you’re expecting bulk fermentation to finish in the timeframe a recipe suggests but your kitchen is cooler than the recipe assumed, the dough simply hasn’t had enough time yet.

How to check: Measure your actual dough temperature with a probe thermometer, not the room temperature. Dough often runs cooler than the ambient kitchen temperature, especially if your water was cold when you mixed.

For most home bakers aiming at a 4 to 7 hour bulk fermentation, a dough temperature in the 74 to 78°F (23 to 26°C) range is the comfortable target. Below 70°F (21°C), you’re working slowly. Below 65°F (18°C), fermentation can crawl.

Warming options:

The oven with just the light on (often reaches 75 to 80°F)
A turned-off microwave with a cup of hot water inside
On top of the refrigerator, which generates a little heat
A proofing box, if you bake frequently enough to justify one

The Bulk Fermentation Calculator uses dough temperature and starter percentage to estimate how long bulk fermentation should actually take in your kitchen. If your bulk timeline feels off, running your numbers there will tell you whether you’re just dealing with a temperature gap.

Third: Time

This one is easy to overlook because it feels too simple, but: your dough might not be done yet.

Recipes are written with assumed conditions — a starter at peak activity, a dough temperature around 75°F (24°C), a kitchen that isn’t drafty or unusually cool. If your conditions vary from those assumptions, the timeline varies too. A recipe that says “bulk ferment 4 to 5 hours” might mean 7 to 8 hours in your kitchen. That’s not a failure — it’s just how sourdough works.

Signs the dough needs more time, not a diagnosis:

Some bubbles on the sides and top but volume hasn’t increased much yet
Dough feels slightly tighter and less extensible than when you started
It’s been 3 to 4 hours and you’re in a cool kitchen

Give it more time before declaring it broken. Check in every hour, look for bubbles along the container walls, and wait for that 50 to 75% volume increase before deciding something is wrong.

Fourth: Ratio Problems

If your starter is active, your temperature is reasonable, and you’ve given it enough time — look at your recipe ratios.

A few places where ratios go wrong:

Too little starter. A very low inoculation rate (5% or below) means fermentation moves slowly. This isn’t always a problem — low-inoculation doughs are used intentionally for long, cold ferments — but if you weren’t expecting a 12-hour bulk at room temperature, you may have measured your starter incorrectly or scaled it down without realizing it.

Scaling errors. If you changed the batch size but didn’t adjust all the ingredients proportionally, the ratios are off. This is more common than it sounds, especially when people scale recipes in their head or adjust only the flour and water. The Recipe Scaler handles the proportions automatically, starter included, so nothing gets left at the wrong ratio.

Too much salt. Salt inhibits fermentation. It’s a necessary ingredient — it controls the rate of fermentation and develops flavor and gluten — but too much salt added directly to the starter, or a significant weighing error, can slow or suppress the rise. Standard salt percentages in sourdough run around 1.8 to 2.2% of flour weight.

Hydration. Very high hydration doughs can be harder to read. A 85% hydration dough may not look like it’s risen because the wet, open structure doesn’t hold its shape the same way a stiffer dough does. If you’re not sure whether your hydration is in a reasonable range for your flour and recipe, the Hydration Calculator can help you check your numbers before your next mix.

When to Accept the Bake (and When Not To)

Sometimes a dough that hasn’t risen as much as expected is still worth baking. A slightly underproofed loaf often produces a dense crumb but an edible, decent-tasting loaf. It won’t be your best work, but it’s not a loss either.

Bake it if:

It’s been 12 or more hours, there’s some fermentation activity, and you need to make a decision
The dough smells mildly tangy and yeasty, not like alcohol or acetone
You want to see what you get and learn from it

Don’t bake it if:

There are zero signs of fermentation after 8 hours with an active starter and reasonable temperature — the result will be a gummy, dense brick
The dough smells strongly of alcohol or very sharp acid, which can indicate it went wrong somewhere beyond just timing

If you bake a dough that didn’t rise and get a dense, gummy loaf — that’s useful information. It tells you the fermentation wasn’t there. Work backward to which variable was off and adjust it for next time.

A Quick Diagnostic Checklist

Run through this when your dough isn’t rising:

Did your starter double and dome after its last feeding? If no — starter is the issue.
What is the actual dough temperature? If under 70°F (21°C) — temperature is likely the issue.
How long has it actually been? If under 5 hours in a cool kitchen — it may just need more time.
Did you use the right amount of starter? Check your recipe math against your actual measurements.
Did you scale the recipe? If yes, confirm all ingredients scaled proportionally.
Any changes to flour, water, or environment recently? Changing variables changes outcomes.

Most cases resolve at step one or two.

FAQ

Why isn’t my sourdough rising during bulk fermentation? The most common causes are a starter that isn’t active enough, dough that’s too cold, or not enough time. Check your starter first — it’s the root cause in the majority of cases. If your starter is strong, check your dough temperature and compare your bulk timeline to what’s realistic for your kitchen conditions.

Can sourdough rise if my starter isn’t at peak? It can, but inconsistently. Starter used before peak (on the way up) tends to produce a slower, less predictable rise. Starter used after peak has already consumed much of its available food and produces less gas. For the most reliable rise, aim to mix your dough when the starter is at or near peak activity.

Will sourdough eventually rise if I just wait longer? Sometimes. A dough in a cool kitchen may simply need more time than the recipe suggests. But a dough with a weak starter or serious ratio problems won’t rise regardless of how long you wait. If it’s been 8 to 10 hours at a reasonable temperature with no signs of fermentation, waiting longer won’t help.

Does salt stop sourdough from rising? Salt slows fermentation, but at normal percentages (1.8 to 2.2% of flour weight) it doesn’t prevent rising. A significant salt measurement error — or adding salt directly onto the starter — can suppress fermentation more meaningfully. Weigh your salt carefully.

Why did my sourdough rise during bulk but not during the final proof? This usually means the dough was overproofed during bulk. When fermentation goes too far in bulk, the gluten structure weakens and the dough can’t hold gas properly during the final proof or in the oven. A flat final proof after a good-looking bulk is often a signal to shorten bulk slightly next time.

My sourdough rises but then collapses. What’s happening? Overproofing. The dough rose past its peak, the gluten degraded, and it couldn’t hold the gas structure anymore. The fix is to catch it earlier in the next bake — look for 50 to 75% volume increase during bulk rather than waiting for maximum rise.

Still not sure where your rise is going wrong? Start with your starter. The Starter Feeding Calculator helps you build a feeding routine that gets your starter to consistent peak activity before every bake — which solves the problem at the root.