Thermal Liners
Insulated Thermal Liners for Chilled and Frozen Shipping
Australian-made carton liners with 50% recycled content, stocked in Villawood
Our thermal liners fit inside a standard carton and turn it into an insulated shipper. The reflective layers slow heat getting in, so your gel packs last longer and chilled or frozen goods arrive at the right temperature. They suit fresh food, meal kits, seafood, pharmaceuticals and lab samples, and take up far less storage space than foam eskies. The range now includes 50% recycled content (25% post-consumer and 25% post-industrial).
New to cold chain shipping? Check the carton fit guide below, try a starter kit with matched liners, gel packs and cartons, or ask us for advice.
Why use thermal liners?
A thermal liner is the simplest way to turn everyday cartons into thermal packaging. It slows the temperature change inside the box, while gel packs do the actual cooling. Together they keep chilled and frozen goods safe for the trip.
Not Sure How Long Your Pack Will Hold?
Tell us what you're sending, how much it weighs, the temperature it needs to stay at and how long it's in transit. Our Villawood team will suggest the right liner, carton and gel pack setup.
Power Packaging Pty Ltd | Dispatching daily from our Sydney warehouse
Thermal liner sizes and carton fit guide
Each liner is sized to fold neatly inside a matching carton, with enough overlap to close over the top. Choose the liner that matches your box.
| Thermal liner | Carton per pack | Fits |
|---|---|---|
| 650 x 625mm | 60 | Small freezer grade box (390 x 285 x 250mm) |
| 750 x 575mm | 50 | Large freezer grade box (430 x 320 x 265mm) |
| 480 x 280mm + 130mm | 85 | Thermal mailers and pouches, not larger cartons |
Using a different carton? Send us the internal dimensions and we'll tell you which liner fits best.
InsulCartons: an all-in-one option
If you'd rather not pair liners and boxes yourself, InsulCartons give you an insulated shipper in one ready-to-use pack. They're a handy choice for smaller runs, trials or teams that want fewer parts to manage.
How to pack a chilled or frozen shipment
1. Line the carton
Open the liner inside the box so it covers the base and all four sides, with the flaps hanging over the top.
2. Add cooling to the base
Lay fully frozen gel packs on the bottom. Pre-chill the product too, as liners keep things cold but can't cool them down.
3. Pack the product, then more gel packs
Place the product in the middle and add gel packs on top. Fill any gaps so cold air isn't lost to empty space.
4. Close and seal
Fold the liner flaps over the top, then tape the carton closed. Ship as soon as possible after packing.
Thermal liner or foam esky?
For most chilled deliveries, a liner inside a carton does the job at a lower cost and takes up a fraction of the space. For longer trips, heavier frozen loads or hot-weather routes, a polystyrene esky gives more insulation. If you're unsure, start with a cold chain starter kit and run a test shipment.
See the full cold chain packaging range, or read our cold chain packaging guide.
Frequently Asked Questions
Do I still need gel packs with thermal liners?
Yes. Liners slow the temperature change inside the box, but gel packs provide the cold. You need both for chilled or frozen goods.
How long will a thermal liner keep things cold?
It depends on the weight of the product, its starting temperature, how many gel packs you use, the weather and the length of the trip. Tell us your route and we'll recommend a setup.
What size thermal liner do I need?
Match the liner to your carton. The 650 x 625mm liner fits our small freezer grade box, the 750 x 575mm fits the large one, and the 480 x 280mm suits thermal mailers. For other cartons, send us the internal dimensions.
Can thermal liners be used for frozen goods?
Yes, as long as the product is frozen before packing and you use enough fully frozen gel packs. For long trips with frozen loads, a foam esky may be the safer choice.
Can thermal liners be reused?
Undamaged liners can often be reused for internal transfers or return shipments. Check them for tears before each use.
Are thermal liners recyclable?
They contain 50% recycled content. Recycling options for used liners vary by area, so check with your local facility or waste contractor.
Request a Thermal Assessment
Tell us about your shipment and we'll recommend the right liner, carton and gel pack setup.