Reusing Canning Jars - OR NOT? (2024)

One of the most-asked questions from those new to canning: Is reusing canning lids safe? I’ve been canning for many years, plus I’m a certified Master Food Preserver. Let me explain.

New to canning? Be sure to check out this guide to canning suppliesand be sure to read about different canning jar sizes.

Can You Reuse Canning Lids for Canning?

The simple answer is no. But I think it’s important for you to understand why.

There is a very vocal contingent of home canners on social media who embrace the motto, “my kitchen, my rules” and vociferously argue that their grandma never died from the old ways, so they’re going to continue using those methods. My goal is not to convince these folks that their safety is at risk, but to help first time canners understand how to do so safely and with good success. This is one of those occasions.

The canning jar system allows for reuse of the glass jars and the metal bands that hold the lids in place during processing. There’s an initial investment up front, but once you own this equipment, you can use it for years and years. (The metal screw bands can rust over time, though.)

Metal canning lids (aka flats) need to be new for every jar of food you preserve, whether water bath canned or used for pressure canning.

New Lids

New canning lids have a sealing compound (usually red) around their perimeter. When heated during processing — in a water bath canner OR pressure canner — this sealing compound softens and molds to the rim of the jar. This is what creates the vacuum seal to make those jars shelf stable. New lids will readily create that airtight seal.

These unused lids are meant to for a single use only. Once they’ve had their first use, they become unfit for the canning process, though they do have a variety of uses. See below for some ways to use old lids.

Used Lids

Used lids will retain the imprint of the jar rim from its last use. As you can see on the lid below, the gasket compound is compressed and indented. Setting this on Mason jars results in less area actually touching the jar rim and may prevent a good seal. Using them a second time means that seal failure is a real risk.

What is Seal Failure?

There are two levels of seal failures that you may experience. One, is that upon removing canning jars from the canner, there’s no vacuum because the jar never sealed. These jars can be placed in the refrigerator; use the contents within a reasonable amount of time.

The second kind of seal failure is when the jar seems to be sealed, but over time the poor seal allows the lid to loosen and allow in oxygen. Jars with a compromised seal may develop mold or harbor dangerous bacteria. With this,home canners risk losing the canned product and a lot of work is wasted.

Preparing Canning Lids for Home Canning

The guidelines for safe canning procedures change over time. It used to be recommended that lids and rings were simmered in hot water before using them. This is no longer required. It won’t hurt to put the lids in hot water, as long as you don’t boil them, but it’s unnecessary. (This is good news for those of us who are in the habit of heating the lids before canning!)

Overheating canning lids by boiling can cause the plastisol to become too thin to create a good seal.

It’s a good idea to inspect new canning lids before use to make sure they’re in good condition. If you use high quality conventional canning lids, it’s unlikely that you’ll see any flaws, but it does happen on occasion, and this can prevent the proper seal from happening.

Once you’ve given the canning jar lids a once-over, wash them in soapy water and set aside on a clean towel so they’re ready to use.

Reusable Canning Equipment

The good news is, the lids are the only portion of the conventional canning jar system that can’t be reused.

Glass canning jars can be washed and reused from year to year. I’ve collected a good quantity of jars over the years by keeping my eyes open at garage sales for canning equipment.

If you’re looking for second-hand jars, just remember that jars with small chips around the rim should not be used for home canning, as the chip can compromise the seal. (They’re fine for storing dry goods, though.)

Like canning lids, metal rings (also called bands) also come in both standard and wide mouth sizes. These are screwed over the lid to hold the lid in place during the canning process.

Once your jars have cooled and the lid is sealed, rings are removed forlong-term storageand can be used to process another batch of jars.

Saving Money with Reusable Lids

If you’re intent on using canning lids more than once for home food preservation, think about investing in somereusable lids. There are a couple of brands to consider; both Tattler and Harvest Guard make two-part lids that can be reused from year to year. Because they are more expensive, I use these on home canned goods that I know I won’t likely give away as gifts, such as broth.

Having a stash of these reusable lids for canning purposes can come in handy if we ever see another shortage of canning equipment, as we did in 2020.

How do Reusable Canning Lids Work?

These reusable lids are a two part canning lid made of a plastic disk and a separate rubber seal. The plastic lid has a lip on it that helps to secure the rubber ring in place.

It’s set in place just like the metal lids, so that the rubber part sits right on the jar rim. Twist a metal screw band on to hold the lid in place.

The guidelines for required headspace are a little different when using these lids. Follow the manufacturer’s instructions to assure a good seal.

The big difference with these lids is that it’s harder to tell if they are sealed. Instead of the pop tight metal lids like those from Ball, you test these by using your fingertips to lift a cooled jar by the lid. If the lid remains intact with the weight of the jar pulling on it (hey, gravity!), it’s considered sealed. It feels a little risky to hold a full jar above the countertop with such a small hold on it, but if Tattler says this is how to check for a proper seal, this is how we do.

Note that there will be some changes in headspace when using these jar lids. Follow the instructions included with the reusable lids to make sure the jars seal properly.

Weck Jars

Another, different type of jar to consider is the Weck brand jar. These jars are in a category of their own, and frankly, much prettier than their more pedestrian counterparts. Both the jars and lids are made from glass, and thus reusable. The sealing ring is a separate rubber piece and also reusable.

The sealing process with a Weck jar requires a couple of metal clips that hold the rubber ring and glass lid in place during processing. Weck is a European company and while the jars are available online, you won’t find them as readily available in the USA. These jars tend to be substantially more expensive than ball jars, too, so using them is an investment.

What to Do With Old Canning Lids

While used lids cannot be used for canning, don’t toss them into the recycle bin quite yet.

• You can reuse lids to store dry food items in the pantry.
• Used lids are perfectly fine for making refrigerator pickles, since a seal isn’t critical here.
• Fermented items can be closed up with used canning lids.
• Reusing lids as garden markers is another clever option.

More on Canning at Home

• Canning Equipment: What You Need to Get Started
• Get these Printable Canning Labels
• Is Instant Pot Canning Safe?
• How to Use a Food Mill for Canning
• Step-by-Step Guide to Canning Jam and Jelly
• All About Pressure Canning
• Use this Pantry Inventory System to Track Food Storage
• Easy Recipes for the Novice Home Canner