Tamper-Evident Inliners for Glass Jars: How They Work and How to Apply Them
Written by Lia Thompson, packaging specialist at Creative Labz. Last updated October 3, 2026.
A tamper-evident inliner is one of the cheapest upgrades you can make to a glass jar. It's a thin seal that sits inside the lid and bonds to the rim of the jar when you close it. Until a customer opens the jar, that seal keeps air out and proves nobody has been inside. Once it's broken, it can't be put back the way it was.
This guide covers what tamper-evident inliners are, how pressure-sensitive inliners work, how to apply them correctly, and which jars they fit.
What Is a Tamper-Evident Inliner?
An inliner (or cap liner) is a disc that sits inside a jar lid. A tamper-evident inliner is designed to seal against the jar's rim, so opening the jar visibly breaks or lifts the seal. Customers can tell at a glance whether the product has been opened since it was packed.
Our tamper-evident inliners are 48mm pressure-sensitive foam liners made to fit our 3.5g glass flower jars and 28g glass concentrate jars.
How Pressure-Sensitive Inliners Work
Pressure-sensitive inliners don't need heat or special equipment. When you tighten the lid, the pressure presses the liner against the jar's rim and creates a seal. When the customer opens the jar, the seal lifts away from the rim, showing that the jar has been opened.
That makes them a good fit for small and mid-size brands. There's no induction sealer to buy, and they work with the jars you already use.
Why Use Inliners on Cannabis Jars?
- Tamper evidence. Customers and retailers can see that a jar is untouched, which builds trust.
- A tighter seal. The liner closes small gaps between lid and rim, helping keep air and moisture out and odor in.
- A professional finish. A sealed jar feels like a retail product, not something packed by hand in a back room.
- Support for compliance. Many markets expect tamper-evident packaging. Inliners are one way to provide it. Check your state's specific rules.
How to Apply Tamper-Evident Inliners
- Check the fit. Make sure the inliner matches your jar. Ours fit our 3.5g glass flower jars and 28g glass concentrate jars.
- Place the liner in the lid. Press it flat into the lid so it sits evenly.
- Clean the rim. Wipe away any flower dust, trichomes, or residue. A clean, dry rim seals best.
- Fill the jar, leaving the rim clear.
- Tighten the lid firmly and evenly. Steady pressure is what creates the seal.
- Test one. Open a sample jar to confirm the seal formed and lifts cleanly.
Pairing Inliners with Other Tamper-Evident Features
For extra protection, combine inliners with:
- Clear tamper-evident shrink bands around the lid and neck
- Tamper-evident stickers across the lid
- Strain and weight jar labels for a complete, compliant look
For more on keeping flower fresh in jars, read How to Store Weed in a Glass Jar to Keep It Fresh.
Frequently Asked Questions
Do I need a machine to apply pressure-sensitive inliners?
No. Pressure-sensitive inliners seal when you tighten the lid by hand. Induction-seal liners are a different type that require an induction sealer.
Can an inliner be resealed after opening?
The lid can still be closed, but the tamper-evident seal won't return to its original state. That's what makes it tamper-evident.
Do inliners help keep cannabis fresh?
Yes. By closing small gaps between the lid and rim, they help keep air and moisture out until the jar is first opened.
Seal Every Jar
Creative Labz carries tamper-evident inliners in packs from 25 to 1,000, plus the glass jars, shrink bands, and labels to complete your packaging.