How long can homemade simple syrup last in fridge?


Homemade simple syrup is a handy ingredient to have in your fridge. It can add sweetness to drinks, desserts, and more. But since it’s homemade without preservatives, you may wonder – how long does homemade simple syrup last? Here’s a quick answer:

Homemade simple syrup will last 2-3 weeks in the fridge when stored in an airtight container. Keeping it cold and covered prevents mold growth and evaporation which leads to thicker syrup. Properly stored, it stays fresh for up to a month.

In this article, we’ll dive into more details on maximizing the shelf life of homemade simple syrup. We’ll cover:

  • What homemade simple syrup is
  • How it’s made
  • What causes it to go bad
  • Storage tips
  • How to tell if it’s gone bad
  • Does different sugar types matter?
  • Can you freeze it?
  • Substitutions once it expires

Let’s start with the basics…

What Is Simple Syrup?

Simple syrup is a mixture of sugar and water that’s heated until the sugar fully dissolves. It’s an easy way to sweeten drinks, desserts, and other recipes.

The two main ingredients are:

Sugar – Typically granulated white sugar, but other types can be used too. The sugar adds sweetness and thickens the syrup slightly.

Water – Plain water. The amount of water determines how thin or thick the finished syrup will be.

That’s it – just sugar and water! But in what ratio?

Simple Syrup Ratio

The basic simple syrup ratio is:

1:1 – 1 cup sugar to 1 cup water. This makes a standard simple syrup.

You can also make:

2:1 – 2 cups sugar to 1 cup water. This results in a thicker, richer syrup.

1:2 – 1 cup sugar to 2 cups water. This makes a thinner, lighter syrup.

The 1:1 ratio is the standard and works great for most uses. The thicker 2:1 ratio is popular for coffee drinks since the syrup is less likely to sink. And the thinner 1:2 ratio can be nice for more delicate desserts or drinks where you don’t want an overly sweet taste.

Now let’s go over the easy steps to make it…

How to Make Simple Syrup

Here is an overview of how to make standard 1:1 simple syrup:


  • 1 cup granulated white sugar
  • 1 cup water


  1. Combine sugar and water in a small saucepan.
  2. Heat over medium, stirring occasionally, until the sugar dissolves.
  3. Once the sugar has fully dissolved, remove from heat.
  4. Let cool for about 30 minutes before transferring to an airtight container.
  5. Store in the fridge.

It’s that easy! The key things to remember are:

  • Heat the mixture only until the sugar fully dissolves. Don’t let it boil.
  • Let it cool before refrigerating. Storing hot syrup can lead to condensation which promotes mold growth.
  • Use an airtight container. Mason jars or bottles with tight lids work well.

Properly stored homemade simple syrup will last 2-4 weeks in the refrigerator.

Now let’s look at what factors can shorten its shelf life…

What Causes Homemade Simple Syrup to Go Bad?

A few key things can lead to homemade simple syrup going bad sooner:

Improper Storage

Exposing the syrup to air and warmth shortens its shelf life. Storing it in a loosely closed or warm area gives mold and bacteria a chance to grow. An airtight container in the fridge prevents this.

Added Moisture

Any water droplets introduced to the syrup after it’s made provide a breeding ground for mold. Always use dry utensils and containers.


Boiling the syrup can change the sugar’s structure, making it more prone to crystallization. This results in grainy syrup that hardens faster. Keep the heat low and avoid boiling.


Dirty cooking tools or containers introduce bacteria and other microbes. Always use clean equipment when making and storing syrup.

So as long as you follow proper syrup making and storage methods, your homemade simple syrup can last 2-4 weeks refrigerated.

For maximum freshness, here are some extra tips…

How to Store Simple Syrup

Here are some tips for proper storage to extend the shelf life:

  • Use sterilized glass jars or bottles. Wash thoroughly in hot soapy water first.
  • Let syrup cool completely before refrigerating. Storing hot syrup causes condensation which can promote mold growth.
  • Make sure lids are tightly sealed.
  • Store in the back of the fridge furthest from the door. This helps minimize temperature fluctuations.
  • Wipe down exterior of containers to remove drips or spills that can harbor bacteria.
  • Refrigerate any leftovers immediately after use.

With proper sealing and refrigeration, homemade simple syrup lasts 2-4 weeks.

How can you tell if it’s gone bad?

How to Tell If Simple Syrup Has Gone Bad

Watch for these signs that your homemade simple syrup has spoiled:

  • Mold growth – Look for fuzzy mold either floating in the syrup or around the lid. Toss the syrup if you see any mold.
  • Fermentation bubbles – Bubbles inside the syrup or a bulging lid can indicate yeast or bacteria growth.
  • Strange smell – Syrup may give off sour, rotten, or alcoholic odors.
  • Crystallization – Sugar crystals or graininess, especially around the edges, is a sign of sugar molecules clumping together over time.
  • Cloudy syrup – Fresh syrup is clear. Cloudiness indicates microbes or separation of sugar and water.
  • Changed consistency – Syrup may become abnormally thick like honey or thin like water.

When in doubt, discard homemade simple syrup after 3-4 weeks. The small savings isn’t worth risking foodborne illness.

Now let’s look at some factors that affect shelf life…

Does Sugar Type Affect How Long Simple Syrup Lasts?

Yes, the type of sugar used can impact shelf life. Simple syrup can be made with white sugar, brown sugar, organic cane sugar, agave, and other sweeteners. Here’s how some compare:

White Sugar – Lasts 2-4 weeks. Most shelf stable option thanks to its highly refined and purified structure.

Brown Sugar – Lasts 2-3 weeks. The molasses content can cause some crystallization over time.

Organic Cane Sugar – Lasts 2-3 weeks. Minimally processed but may have more variation in molasses content.

Agave Nectar – Lasts 1-2 weeks. The fructose makes it more susceptible to microbial growth. Store agave syrup in smaller batches.

Maple Syrup – Lasts 2-3 weeks. Has antimicrobial properties from the tree bark used but can mold eventually.

Honey – Lasts 3-4 weeks. Naturally antimicrobial thanks to enzymes that produce hydrogen peroxide. Keep in mind honey will overpower delicate flavors.

So while syrup made with white sugar stays fresh a few weeks longer, brown sugar or organic cane sugar varieties still last 2-3 weeks. For the health benefits of less refined sweeteners, a shorter shelf life may be an acceptable trade-off.

On the other hand, delicate syrups like agave deteriorate more rapidly. Opt for small batch recipes so none goes to waste.

Can You Freeze Simple Syrup?

Yes, simple syrup can be frozen to extend its shelf life significantly. Here are some freezing tips:

  • Let syrup cool completely before freezing. Transferring hot syrup to the freezer can crack glass containers.
  • Leave 1/2 inch headspace in containers to allow for expansion.
  • Use freezer-safe containers. Mason jars, freezer bags, or plastic containers all work well.
  • Syrup may crystallize slightly but will liquefy again after thawing in the fridge.
  • Label containers with type of syrup and date.
  • Syrup thawed in the refrigerator lasts about 2 weeks.

Properly frozen, simple syrup stays fresh and usable for 6-12 months. Freezing is an easy way to make large batches of syrup ahead of time.

If your syrup does eventually expire, are there any substitutions? Let’s look…

Simple Syrup Substitutes

If you discover an old batch of syrup past its prime, all is not lost. Here are some handy ingredient swaps:

  • Granulated sugar – Use 1/2 the amount of syrup called for. Mix with any liquids to dissolve.
  • Brown sugar
  • Honey – Use 3/4 the amount syrup would require.
  • Maple syrup
  • Agave nectar
  • Fruit juice – Opt for mild juices like apple to avoid overpowering flavors.

You can also make a quick simple syrup replacement by stirring superfine or turbinado sugar into hot water until dissolved. Let cool before using.

With some creative substitutions, you can still sweeten up drinks and desserts even without homemade simple syrup on hand.


With proper storage and handling, homemade simple syrup easily lasts 2-4 weeks refrigerated. The keys are:

  • Storing in an airtight container in the fridge
  • Making sure equipment is sterile
  • Avoiding moisture and temperature fluctuations
  • Keeping syrup away from air exposure

Check periodically for any signs of mold, crystallization, or fermentation. When freezing simple syrup, allow headspace for expansion and use freezer-safe containers.

While white sugar makes the longest lasting syrup, you can still get 2-3 weeks from organic, brown, or other sugar varieties too. With the right storage, you can enjoy homemade simple syrup for all your sweetening needs.

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