The Complete Guide to Twist-Off & Button Lids
Posted by The Wares Team on 22nd Jul 2026
Understanding Twist-Off Lids
Whether you're making homemade strawberry jam, bottling honey from your own hives, preserving seasonal chutneys or launching a new artisan food business, choosing the right lid is just as important as choosing the right glass jar. The right closure helps create a reliable seal, protects your product and ensures your finished jars look as good as the contents inside.
With so many different terms in use—twist-off lids, preserving lids, button lids and replacement jam jar lids—it can be difficult to know which one you need and how they actually work.
At Wares of Knutsford, we regularly help everyone from first-time home preservers to commercial food producers choose the right lids for their products. Along the way, we're often asked questions such as:
- What's the difference between a standard twist-off lid and a button lid?
- Should I tighten my lid as much as possible?
- Can preserving lids be reused?
- Why didn't my jar seal properly?
- Which lid is best for honey?
- What size lid do I need?
Whether you're preserving a handful of jars in your kitchen or packing thousands of products for sale, understanding how twist-off lids work will help you achieve a safe, reliable and professional finish.
In this guide, we'll explain how twist-off lids create an airtight seal, when to use button lids, common sealing mistakes to avoid, and how to get the best results every time.
What Is a Twist-Off Lid?
Twist-off lids are the most common type of closure used on glass preserving jars throughout the UK and Europe.
Designed to create a secure, airtight seal, they are suitable for a wide variety of products including:
- Jam
- Marmalade
- Chutneys
- Pickles
- Relishes
- Sauces
- Curds
- Honey
Twist-off lids are manufactured from food-grade steel and feature an internal sealing compound (sometimes referred to as the liner or gasket), which creates the seal against the glass jar. They are designed for food contact and are suitable for acidic products such as fruit preserves, pickles and chutneys.
Available in a wide range of sizes and range of colours, twist-off lids are used by everyone from home preservers making a few jars each year to large commercial food producers filling thousands of jars every day.
How Does a Twist-Off Lid Work?
Although it might seem that tightening the lid creates the seal, that's only part of the process.
The real seal is created by pressure.
For hot-filled products such as jam, marmalade and chutneys, the preserving process works like this:
- The hot product is filled into a clean glass jar.
- The rim of the jar is wiped clean to remove any residue.
- The lid is applied and tightened until finger tight.
- As the product and the air inside the jar cool, they contract.
- This creates a vacuum inside the jar, pulling the lid firmly against the sealing compound and producing an airtight seal.
The vacuum is what keeps the contents protected and helps maintain freshness.
Why Finger Tight Is Best
One of the biggest misconceptions is that the tighter the lid, the better the seal.
In reality, overtightening can actually work against you.
A twist-off lid should normally be applied until it is firmly finger tight—secure enough to hold the lid in place while still allowing the sealing compound to work as intended.
Overtightening can:
- Compress the sealing compound excessively.
- Distort the lid.
- Make jars unnecessarily difficult to open.
- In some cases, interfere with the formation of a proper vacuum.
A good seal comes from the vacuum created during cooling—not from applying as much force as possible.
Hot Filling vs Cold Filling
Not every product is filled at the same temperature, and understanding the difference helps explain why lids behave differently.
Hot Filling
Products such as jams, marmalades, chutneys and many sauces are typically filled while hot. As the product cools, it naturally creates a vacuum inside the jar, producing the familiar airtight seal.
This is why button lids often "pop down" after the jars have cooled.
Cold or Warm Filling
Products such as honey are usually filled at much lower temperatures. Some producers gently warm the honey to improve its flow, but it is generally not considered a hot-filled product.
In these cases, the lid still provides a secure, hygienic and airtight closure, but the vacuum may be less pronounced than with traditional preserves.
Using Twist-Off Lids for Honey
Honey is one of the most popular products packaged in glass jars. Unlike jam or chutney, honey doesn't rely on hot filling for preservation. Its naturally low moisture content gives it an exceptionally long shelf life when stored correctly.
Most beekeepers and commercial honey producers either fill at room temperature or gently warm the honey to make it easier to pour. The twist-off lid then provides a secure, airtight closure that helps protect the honey from moisture and contamination.
A quality twist-off lid offers several advantages for honey producers:
- An attractive, professional finish.
- A reliable airtight seal.
- Protection from dust, moisture and contaminants.
- A wide choice of colours and decorative designs.
- Excellent compatibility with retail and wholesale packaging.
If you're using button lids, you may notice that the button doesn't always pull down as dramatically as it does with hot-filled jam. This is perfectly normal and doesn't necessarily indicate a poor seal.
Did You Know?
We are currently expanding our range of twist-off lids with a honey-specific sealing compound, developed specifically for honey packaging. If you're a beekeeper or commercial honey producer, we'd be delighted to help you choose the most suitable lid for your jars. Contact us for more information
What Is a Button Lid?
Button lids, sometimes referred to as safety button lids, are one of the most popular choices for home preserving. They work in exactly the same way as a standard twist-off lid but include one important feature—a small raised button in the centre of the lid.
The purpose of the button is to provide a simple visual indication that a vacuum has formed inside the jar after sealing.
Before a jar is filled and sealed, the button will usually sit slightly raised and may move when pressed. As a hot-filled product cools, the vacuum created inside the jar pulls the button down. Once sealed, the button should remain in this position until the jar is opened.
When the lid is first opened, you'll often hear the familiar 'pop' as the vacuum is released and the button returns to its original position.
Button lids are particularly popular with home preservers because they offer extra reassurance that a vacuum has formed correctly. They're commonly used for jams, marmalades, chutneys, pickles, sauces and other hot-filled preserves.
Although the button provides a useful indication that the jar has sealed, it should always be considered alongside good preserving practices. It indicates that a vacuum has formed, but it does not confirm that the contents have been processed correctly or are safe to eat.
Common Reasons a Jar Doesn't Seal Properly
If you've ever finished a batch of jam only to find one or two lids haven't sealed, you're not alone. Fortunately, many sealing issues are easy to avoid.
Here are some of the most common causes.
The Jar Rim Wasn't Clean
Even a small amount of jam, chutney or syrup left on the rim of the jar can prevent the sealing compound from making full contact with the glass.
Before fitting the lid, always wipe the rim with a clean, damp cloth to remove any residue.
The Lid Was Overtightened
Many people assume that tightening the lid as much as possible will create a better seal.
In reality, twist-off lids should only be tightened until they are firmly finger tight.
Overtightening can compress the sealing compound too much, distort the lid and make it more difficult for the vacuum to form correctly as the contents cool.
The Lid Was Damaged
Before using any lid, it's worth giving it a quick inspection.
Avoid using lids that are:
- Dented
- Bent
- Rusty
- Scratched on the sealing surface
- Damaged around the edge
Even minor damage can affect the quality of the seal.
The Jar Was Overfilled
Leaving the correct amount of headspace is an important part of successful preserving.
If a jar is filled too close to the top, food can become trapped between the rim and the sealing compound, preventing a proper airtight seal.
Always follow your recipe's recommended headspace.
The Product Wasn't Hot Enough
For products that rely on hot filling, such as jams, marmalades and chutneys, filling at the correct temperature is essential.
As the hot product cools, it creates the vacuum that pulls the lid firmly onto the jar.
If the product has cooled too much before filling, the vacuum may be weaker or may not form at all.
Honey is an exception, as it is typically filled at much lower temperatures and does not rely on the same hot-fill preserving process.
Reusing Old Lids
While glass jars can often be reused many times, lids naturally wear over time.
The sealing compound may become compressed or damaged after repeated use, making it more difficult to achieve a reliable seal.
If you're preserving food for long-term storage, using new lids is generally the best option.
How to Check Your Seal
Once your jars have cooled completely, it's worth checking that each one has sealed correctly.
For button lids:
✔ The button should remain pulled down.
✔ The lid should feel firmly attached to the jar.
✔ There should be no movement when the centre button is gently pressed.
If the button remains raised or moves up and down after cooling, a proper vacuum may not have formed. In this case, the contents should be refrigerated and consumed promptly or reprocessed using a new lid, following your preserving recipe.
Looking After Your Lids
Whether you're preserving at home or filling hundreds of jars for sale, taking care of your lids will help you achieve the best results.
Store lids in a clean, dry environment and avoid exposing them to moisture before use. Always check lids for damage before fitting them to your jars, and make sure you're using the correct size for the jar you're sealing.
Using quality lids and following good preserving practices will give you the best chance of achieving a reliable seal every time.
