Shipping air is expensive. If you are running an e-commerce fulfillment operation in the UK, you already know the frustration of picking a product, grabbing a standard slotted carton, and realising you have to fill 60% of the space with brown paper, air pillows, or loose-fill peanuts just to stop the item rattling around.
That empty space is called void fill, and in high-volume e-commerce, it is a hidden drain on bottom-line profitability.
Between rising courier fees calculated on volumetric weight (DIM weight) and growing pressure from customers to eliminate over-packaged, eco-unfriendly parcels, minimising empty space isn’t just a sustainability goal—it’s a major cost-cutting strategy.
Here is a practical guide on how to reduce void fill in e-commerce packaging, optimise your warehouse workflows, and keep your fulfillment costs as lean as possible.
Look at What You’re Shipping
Many B2B companies buy a very limited selection of box sizes in high volumes to chase bulk discounts. While buying fewer SKUs keeps the initial procurement simple, it inevitably forces your packing team to use oversized boxes for smaller orders, relying heavily on cardboard boxes packed with filler to bridge the gap.
Instead of guessing your box requirements, run a data audit on your last three to six months of orders:
- Identify your top 20% most popular products or multi-item baskets (these usually make up 80% of your shipping volume).
- Match those profiles to specific, snugly sized boxes.
- Expanding your range from 3 standard box sizes to 6 or 8 highly targeted sizes reduces void fill consumption by 30% or more, easily offsetting any minor drop in volume discounts.
Consider Cardboard Box Alternatives
For smaller, flat, or semi-fragile goods (cosmetics, electronics, fashion accessories, books), a traditional square box is often the wrong tool for the job.
Looking at alternatives such as our book wrap mailers, or even padded envelopes can save you money on delivery costs as well as void fill.
- Book Wrap Mailers: Ideal for books or anything of a similar shape and size, these fold around the package conforming to near the exact size.
- Padded Envelopes: When shipping smaller, flat, or semi-fragile good padded envelopes are ideal. For items such as jewelry, electronics, cosmetics, and fashion accessories these can be a great alternative to boxes.
Standardise Packing with Simple SOPs
Often, void fill isn’t a design problem; it’s a behavioral one. When a warehouse gets incredibly busy, packers work on instinct. If they are unsure whether a product is safe, they default to “overpacking” — grabbing extra bubble wrap or paper out of habit.
To counteract this, introduce brief, visual Standard Operating Procedures (SOPs) at each packing bench:
- Provide clear photos of how the top 10 most common product combinations should be packed.
- Establish clear boundaries (e.g., “If the gap is less than 2 inches, do not use loose fill; use a smaller mailer bag instead”).
- Run periodic quality checks on outgoing parcels to ensure staff aren’t “filling by feel.”
Choosing the Right Void Fill
Sometimes the answer lies in choosing the best void fill for the job rather than trying to eliminate it altogether. We have a range of void filling options, each with their own benefits.
- Foam Roll: Best suited for high-finish, scratch-sensitive surfaces like glass, polished metal, painted components, or stacked ceramics.
- Air Pillows Cushioning: Ideal for filling large, lightweight overhead voids in medium-to-large boxes where the product is robust but needs to stay still.
- Loose Void Fill Packing Peanuts: Most appropriate for irregularly shaped, heavy, or intricate items which need to be suspended in the centre of a box.
- Honeycomb Paper Bubble Wrap: It is highly effective for wrapping cosmetics, wine bottles, and boutique homewares, interlocking with itself so you can wrap tightly without needing excess adhesive tape.
- Packing Paper Rolls & Sheets: Excellent for heavy-duty blocking and bracing or wrapping medium-weight items.
So you may find it cheaper in the long run to invest in a couple of different options rather than taking the one size fits all approach and needing to use more than necessary.
The Payoff
Reducing void fill goes far beyond saving on packing paper. When you right-size your e-commerce shipments, you pack less air. Packing less air means you fit more parcels onto every delivery pallet, drastically dropping your shipping rates with UK couriers who charge based on volumetric size.
Need to optimise your packing benches or audit your current box selection? Check out our full wholesale range of cardboard boxes, bubble wrap, and eco-friendly postal supplies to get your fulfillment operations running at peak efficiency.