How Long Do Cremated Ashes Last After Cremation?


Cake values integrity and transparency. We follow a strict editorial process to provide you with the best content possible. We also may earn commission from purchases made through affiliate links. As an Amazon Associate, we earn from qualifying purchases. Learn more in our affiliate disclosure.

There are many reasons people choose to keep a loved one’s cremains after their cremation. Doing so helps people feel their loved ones are still with them in some capacity. Like burying a body, preserving cremains can also be a sign of respect for the deceased.

Jump ahead to these sections:

That’s why some people wonder, “How long do cremated ashes last?” They want to be certain a loved one’s cremains won’t degrade or decompose soon after they receive them.

There’s no single answer to this question. The amount of time cremains “last” depends on a range of factors. Keep reading to learn what they are, and what you can do to preserve cremains for years.

Tip: If you want to transform your loved one's ashes into a more durable form, Parting Stone can help. Parting Stone lets you turn cremains into beautiful, solidified remains in the form of stones. 

How Long Do Cremains Stay Cremains? 

Cremains are technically what’s left of bone fragments after a cremation. Despite popular misconceptions, they aren’t actually ashes, nor are they genuinely organic material. That means they don’t biodegrade naturally.

However, they can “stop being cremains” in a sense because they may mix with the soil, water, or air to such a degree that they no longer remain as intact as they may have been when a family first receives them. The following points explain how long it may take for this to happen based on where someone chooses to store or distribute cremains.

» MORE: An online memorial is a perfect ending to honor and celebrate someone's life. Create one for free.

In the ground

The specific way in which someone buries cremains in the ground will influence how long it takes for the cremains to degrade and become part of the soil. Some people choose to bury cremains directly into the ground without an urn. In this case, it won’t take them very long to settle in among the surrounding organic material. 

(If you’re considering this option, it’s important to understand that cremains can sometimes harm nearby plant life due to remnants from the cremation process. Consult with an expert if you’re worried about this possibility.)

Others bury cremains but still keep them in an urn. Below, this blog entry will describe how an urn can protect cremains for a very long time, even in the ground. That said, sometimes people decide to cremate loved ones in the first place because they want to minimize their environmental impact. These people may then decide to bury the cremains in biodegradable urns, which can take anywhere from one to 20 years to biodegrade. The cremains will quickly join the soil once the biodegradation is complete.

In the water or ocean

When planning a scattering ashes ceremony that involves depositing cremains into the ocean or another body of water, you need to make certain key decisions. For instance, you need to decide if you want to directly scatter the ashes into the water instead of starting with an urn for the ashes.

Water will distribute cremains fairly quickly. Some people opt to scatter ashes into bodies of water for this very reason. There’s evidence to suggest that, for instance, broken down cremains may help to build “artificial” coral reefs. This comforts loved ones who feel the deceased is still positively contributing to the world even after their death.

However, there are also instances when people want to have some time to pay their respects and mourn during a scattering ashes ceremony. In these cases, they may choose to store the cremains in an urn and place it in the water. 

Experts recommend choosing a biodegradable urn in these circumstances. They don’t want anyone polluting bodies of water with urns that will remain intact for long periods of time. Instead, biodegradable urns provide mourners with more time to say goodbye during a ceremony before the urns break down and the cremains mix with the water.

In an urn 

Cremains can last for a very long time in an urn, as long as the urn has a strong seal. It’s actually not uncommon for archaeologists to find cremated remains from people who lived over a thousand years ago.

Granted, cremation practices in the past weren’t the same as they are today due to the nature of our modern equipment, but these findings indicate urns can theoretically preserve cremains for hundreds or even thousands of years. 

» MORE: Grief can be lonely. Create space for your community to share memories and tributes with a free online memorial from Cake.

How Can You Better Preserve Cremains?

If you’re asking the question “How long do cremated ashes last?” maybe you want to know what you can do to ensure your loved one’s cremains last as long as possible.

Consider the following tips if so. They’ll help you generally understand what you can do to protect post-cremation remains. That said, it’s still a good idea to consult with an expert if preserving a loved one’s cremains is very important to you.

Know (and research) your storage options

Should you decide not to scatter or bury a loved one’s cremains, you’ll have a few storage options to consider. Think about the ways these various storage options may help better preserve the cremains.

Home storage

You can choose to store cremains in an urn somewhere in your home. However, if you do, you need to accept that they might be somewhat vulnerable to theft or destruction for a variety of reasons.

For instance, maybe a major plumbing issue causes unexpected flooding in your home. Depending on the circumstances, the urn holding the deceased’s cremains may fall and break open, the cremains mixing with the water. It’s not a pleasant idea to consider, but it’s the type of situation consider if you decide on keeping cremains at home.

If you're creating a custom urn for your loved one's ashes with a service like Foreverence, home storage is something to consider. How you plan to keep your cremated remains will affect the appearance, material, and size of your custom urn. 

Other options

You don’t have to store cremains in your home if you’re not confident they’ll be safe. For instance, you can choose to store them in a mausoleum, crypt, or columbarium. Just keep in mind that doing so doesn’t guarantee they’ll be safe from theft, destruction, or other potential risk factors either.

That’s why it’s important to conduct thorough research if you decide to store cremains in one of these spots or facilities. If you were choosing a storage facility for personal belongings, you would research local options to ensure you chose a facility with a strong reputation for security.

Take the same approach when looking into crypts, mausoleums, or columbariums. Find out who officially owns or maintains the property, and see if there are any online reviews or other resources describing the measures they take to protect cremains. You can also ask friends or relatives for suggestions if you believe you can trust them to offer reliable advice on this subject.

Choose a strong urn

Regardless of where you choose to store an urn containing a loved one’s cremains, if preserving them for years is among your key goals, you shouldn’t sacrifice quality. Although you do need to account for your budget when choosing an urn, ideally, you should select a durable option that can withstand potential causes of damage. 

Whether you order a customized urn from a company like Foreverence or purchase one from an online marketplace like Amazon or Etsy, you should also ask the expert providing the urn (or a related professional) to demonstrate the proper sealing technique, as well as any maintenance tips they may have. Remember, an urn with a strong seal can keep ashes preserved for a very long time.

» MORE: Online obituary that is 100% free. Honor a loved one beyond a newspaper.

Consider new alternatives

It’s worth noting that you don’t need to limit yourself by only considering traditional methods of preserving cremains, such as storing them in an urn. There are other preservation methods you may want to explore in greater detail.

For instance, it’s becoming increasingly popular for people to store a loved one’s cremains in a locket on a piece of jewelry.

Some designers also offer to infuse pieces of jewelry with cremains or grow diamonds out of your loved one's ashes, like Eterneva. Although you’ll have to be careful to ensure you don’t lose a piece of jewelry containing the cremains of a loved one, you may believe this will be easier than trying to keep them safe in an urn.

How Long Do Cremated Ashes Last? A Complicated Topic

This brief guide likely helped you appreciate that the “lifespan” of cremains can vary. These are all points you may want to keep in mind if you ever cremate a loved one, and are unsure about what you should do with their cremains.

If you're looking for more on cremation, read our guides on cheap ways to display ashes and temporary urns.


  1. “How Long Do Biodegradable Urns Last?” The Living Urn, Biolife, LLC, 24 March 2019,
  2. “Scattering Ashes at Sea Guide: 5 Important Things You Need To Know.” Cremation Institute, Cremation Institute,
  3. Wu, Katherine J. “Archaeologists Find New Way to Determine Sex of Cremated Individuals.” NOVA, WGBH Educational Foundation, 30 January 2019,

Icons sourced from FlatIcon.