How Long Can You Keep Your Sourdough Starter in the Fridge?

The other day I was playing tennis with my friend Danielle, and in between rallies, she started talking about the sourdough bread she makes every week. 

Naturally, my ears perked up.  I told her I’d always wanted to try making my own, but never got around to it because I didn’t have a starter. 

Fast-forward to our next lesson: she showed up with a jar of bubbly sourdough starter tucked in her bag and handed it to me like it was a family heirloom. 

I was officially in.

Of course, once I got home and started reading about my own sourdough starter care, I quickly realized there’s a whole world of advice (and strong opinions!) about how to feed, store, and maintain your starter. 

One question kept coming up: how long can sourdough starter stay in the fridge?

If you’re new to the sourdough journey or looking to simplify your routine, this post has you covered.

Today we’re talking about best practices for storage and how to keep your sourdough culture happy. Let’s dive in!

What Is a Sourdough Starter?

Let’s rewind for a sec. What even is a sourdough starter?

It’s a simple mixture of flour and water that captures wild yeast and lactic acid bacteria from the environment. 

Unlike commercial yeast, which is a single strain, natural yeast cultures in sourdough are complex and give the bread its signature unique flavor and texture.

As your starter rises and bubbles, the yeast produces carbon dioxide, which helps your bread rise. Meanwhile, lactic acid bacteria contribute to both flavor and acidity.

Think of it as a living, breathing pet you feed with fresh flour and water. 

With the right care, your starter can last a long time—even years! Many bakers lovingly maintain established starters that are decades old. 

I have a pizza restaurant client who has had their sourdough starter for nearly fifteen years!

So why do we go through this instead of buying a packet of commercial yeast? 

Because nothing beats the flavor and character that a good natural leavening agent brings to a loaf of delicious sourdough bread.

How to Create Your Own Sourdough Starter

If you’re starting from scratch, making your own sourdough starter is actually pretty easy. 

Here’s what you need:

• Equal parts of flour and equal parts water by weight (start with 50g each).
• A clean jar or glass jar. I love using mason jars.

Best practices:

• Use bread flour, whole wheat flour, or rye flour to kick things off. These flours have more nutrients to feed your growing yeast and bacteria.
• Cover your jar loosely with a tea towel, plastic wrap, or a lid. If you’re using a lid, don’t screw it on too tight because you do want airflow.

The feeding process:

• Each day, discard half your starter (called the sourdough discard) and feed the remaining half with fresh flour and water (again, equal parts).
• You’ll start seeing bubbles and a rise after a few days.

Tools you need:

• Wrap a rubber band around your jar to track how much your starter rises.
• After 5–10 days, you’ll have an active sourdough starter ready to bake. A float test helps confirm. Just drop a spoonful into water and if it floats, it’s ready! 

Feeding Schedule for an Active Starter

Once your starter is mature, you’ll want to keep it strong with a regular feeding process.

At room temperature, feed it once or twice a day for best results.

A typical feeding ratio:

• 1:1:1 — 50g starter, 50g fresh flour, 50g water.
• Adjust to 1:2:2 if your kitchen is warm, to give it more food.

Signs of a healthy sourdough starter:

• Lots of bubbles.
• A sweet, tangy smell (no foul odors!).
• Passes the float test.

Frequent feedings help develop flavor and strength. An unfed starter at room temperature will quickly turn sluggish or go bad.

Different flours:

• Rye flour: fast fermentation, bold flavor.
• Whole wheat flour: adds complexity.
• Purpose flour (AP): neutral and reliable.

When and Why to Refrigerate Your Starter

I get it. Life happens. You’re not always going to bake every day or even every week. And that’s where your fridge comes in. 

Refrigerating your sourdough starter is a good idea when:

• You want to bake occasionally, not daily.
• You’re going away or need a break.
• You want to maintain your starter for a longer period of time with minimal work.

In cold temperatures, the fermentation process slows waaaay down. Your starter will go dormant but stay alive.

This allows you to feed it only every couple of weeks instead of every day.

• A mature starter can handle this beautifully.
• A young starter should spend a few weeks at room temperature first to get strong.

If your starter rises slowly after refrigeration, that’s totally normal! You’ll just need to revive it . More on that in a bit. 

How Long Can Sourdough Starter Stay in the Fridge?

Here’s the most important question of the day: how long can sourdough starter stay in the fridge?

The answer depends a bit on your starter’s maturity, how you store it, and how it was fed beforehand. But here’s a general guide:

• A couple of days to a couple of weeks: Totally safe for any well-fed active starter.
• Longer periods (up to a month or more): Possible with a mature starter that’s been well maintained. I personally recommend feeding it about every 2–3 weeks for best results.
• Long time (1–2+ months): Riskier. The starter will degrade unless stored very stiff (lower hydration starter) or preserved via the freezer method or dried starter (covered below).

Factors affecting shelf life:

• Type of flour: Rye starter may ferment faster than purpose flour or whole wheat flour starters.
• Storage container: Use an airtight lid if you want to prevent hooch buildup and dryness, but burp the jar occasionally.
• Hydration: A stiffer starter stores better than a very wet one.

How to tell if your starter has gone bad:

• Strong alcohol smell or gray/black hooch is okay—just stir and feed.
• Signs of mold (pink, orange, fuzzy growth) = toss it and start over.
• Thin layer of hooch (liquid on top) is normal. Just mix and feed.

What’s the best way to build fridge longevity? Feed your starter really well before putting it away. Give it a hearty meal with equal parts flour and water, let it rise at room temperature, then refrigerate.

Reviving a Cold Starter

When you’re ready to bake again, you’ll want to wake up your cold starter.

Best practices:

1. Take out a small portion of starter (around 50–100g). Leave the rest in the fridge for later use.
2. Feed with equal parts flour and water.
3. Let it sit in a warm spot (~75°F is ideal).

Expect it to take a little bit longer to bounce back after a long stint in the fridge. If it’s been just a couple of days without feeding, one feeding may do it. But if it’s been longer, it may take 2–3 feedings.

You’ll know your starter is ready when it passes the float test again and shows vigorous fermentation activity.

Long Term Storage Options

If you won’t bake for a long period, there are two great long term storage methods:

Freezer method:

• Feed your starter well.
• Transfer a portion of the starter to an airtight container or bag.
• Freeze for later use. It will last several months.
• To revive: thaw in the fridge, then feed as usual.

Dried starter:

• Spread a thin layer of well-fed starter on parchment paper.
• Air dry fully (about 24–48 hours).
• Store flakes in a jar.
• To rehydrate: dissolve flakes in water, then resume regular feedings.

Frequently Asked Questions (FAQs)

Q: How often should I feed my starter when it’s in the fridge?

A: For best results, feed your refrigerated starter every couple of weeks. If you bake more frequently, weekly feedings are great. If you’re stretching it to longer periods, make sure to give it a hearty feed before refrigerating.

Q: Should I store my starter in an airtight container?

A: Yes, an airtight container works well for fridge storage because it prevents the starter from drying out. Just be sure to leave a little space for expansion and burp the lid occasionally. If you prefer, a tea towel or plastic wrap works for shorter fridge stays.

Q: How can I tell if my starter has gone bad?

A: Watch for signs of mold (pink, orange, or fuzzy spots). A thin gray liquid (thin layer of hooch) is normal—just stir it in. Strong, unpleasant smells beyond tangy sourness also mean it’s time to start fresh.

Q: What type of flour is best for fridge storage?

A: You can maintain your starter on purpose flour (AP) for convenience. Some bakers swear by rye flour or whole wheat flour to boost activity before storage. Just keep your feeding schedule consistent with your starter’s preferences.

Q: How long should I give my cold starter before baking?

A: If your starter has been in the fridge for a couple of days, one or two feedings should revive it. After a longer period, plan for a couple of days of frequent feedings in a warm spot to fully reactivate it.

Q: What’s the best way to prepare a starter for long-term storage?

A: Use the freezer method or make a dried starter. For freezing: transfer a portion of the starter to an airtight container and freeze. For drying: spread a thin layer of well-fed starter on parchment paper, dry fully, then store in a jar.

Q: How much starter should I keep in the fridge?

A: You don’t need much starter! Keep a small portion (50–100g) for easy maintenance. You can scale it up when ready to bake. This avoids waste and lets you feed your starter more efficiently.

Q: Does it matter what type of jar I use?

A: Yes. A clean jar, glass jar, or mason jar is ideal. Avoid metal containers, which can react with the acids in the starter. 

Q: What happens if I forget my starter in the fridge for a long time?

A: It happens! A well-fed mature starter can survive a long time in the fridge—sometimes even a couple of months. The key is whether it passes the float test after revival and smells okay. If in doubt, take a small portion and try reviving it separately.

Q: Should I change my feeding process after refrigeration?

A: After a stint in the fridge, your cold starter may need a few frequent feedings to regain strength. Stick to your usual feeding ratio (ex: 1:1:1 or 1:2:2) with equal parts water and fresh flour to rebuild an active starter.

Storing your sourdough starter in the fridge is truly the best way to keep your sourdough journey going without turning it into a full-time job. 

With the right feeding process, even a cold starter will bounce back and give you great results when you’re ready to bake.

I can tell you firsthand — when Danielle handed me that jar of starter on the tennis court, I had no idea I’d be Googling “how long can sourdough starter stay in the fridge?” within 24 hours. 

But now, after a couple weeks of experimenting, feeding, and yes, occasionally neglecting it in the back of the fridge, I’ve learned how to keep it happy. 

And if I can do it, trust me — you can too.

So grab a clean jar, feed your starter well before chilling it, and don’t stress if life gets in the way. 

With options like the freezer method or dried starter as backups, your own sourdough starter can keep going strong. 

Now get baking — and maybe bring a loaf to your next tennis match.