Parcel boxes have to survive a courier network and still be quick to pack. For most online orders the choice comes down to single wall boxes, double wall boxes and crash lock boxes, sized to the product.
Pack Solution sells all three flat packed and per box from its Manchester warehouse, along with the pistol grip tape gun dispensers and fanfold thermal labels that finish a parcel. For Royal Mail size limits, the postal boxes guide goes into more detail.
In This Guide
- Quick Picks: Parcel Boxes For Online Orders
- What Are Parcel Boxes And Shipping Boxes?
- Single Wall Or Double Wall Cardboard Shipping Boxes?
- Crash Lock Boxes For Faster Packing
- How To Match The Box To The Product
- Large Shipping Boxes And Mailing Boxes Large Enough For Bulky Items
- Sealing And Labelling Parcel Boxes
- Cost Per Order And Delivery
- Parcel Box Checklist
- Wrap-Up
- Frequently Asked Questions
Quick Picks: Parcel Boxes For Online Orders
Most sellers need single wall cardboard boxes for everyday orders, double wall cardboard boxes for heavy or fragile ones and crash lock boxes for fast packing.
Best for everyday online orders
Single Wall Cardboard Boxes
Lightweight corrugated boxes in 16 sizes, including a 450 x 350 x 160mm box made to the Royal Mail Small Parcel maximum size.
- 16 sizes from 5 x 5 x 5" to 24 x 18 x 18"
- Flat packed, minimum 5 per size
- Includes an Extra Strong 15.35 x 11.6 x 7.3" size
From £0.35 ex VAT (£0.42 inc VAT)
Choose sizeView product
Best for heavy and fragile parcels
Double Wall Cardboard Boxes
Two layers of fluting give extra strength and better stacking than single wall, for heavier, fragile and high value items.
- 13 sizes from 7 x 5 x 5" to 24 x 24 x 24"
- Minimum 5 boxes, 90 for the 24 x 24 x 24" size
- Price per box falls as you buy more
From £0.59 ex VAT (£0.71 inc VAT)
Choose sizeView product
Best for fast packing of small orders
Crash Lock Boxes
The base locks automatically as the box opens, so only the top needs tape. CL-J takes an A4 item flat.
- 14 sizes from 100 x 100 x 70mm to 426 x 300 x 300mm
- No tape on the bottom
- Minimum 5 boxes per size
From £0.59 ex VAT (£0.71 inc VAT)
Choose sizeView productKey Facts
- Single wall boxes come in 16 sizes, from 5 x 5 x 5" to 24 x 18 x 18", and include a 450 x 350 x 160mm box made to the Royal Mail Small Parcel maximum size.
- Double wall boxes have two layers of fluting and come in 13 sizes, from 7 x 5 x 5" to 24 x 24 x 24".
- Crash lock boxes come in 14 sizes, from 100 x 100 x 70mm to 426 x 300 x 300mm, and need no tape on the base.
- The minimum order is 5 boxes per size, except 90 boxes for the double wall 24 x 24 x 24" size.
- Fanfold thermal labels are 4 x 6" (101.6 x 152.4mm), 1000 to a stack, and need no ink or ribbon.
- Orders placed by 2pm Monday to Friday are dispatched the same working day, and Royal Mail Tracked 48 is free with no minimum.
What Are Parcel Boxes And Shipping Boxes?
Parcel boxes are corrugated cardboard boxes used to send goods through a courier or the post. Shipping boxes and delivery boxes are different names for the same job. So are mailing boxes.
You will also see shipper boxes, which usually means a plain brown corrugated carton with no printing. The board does the work. Corrugated cardboard has a rippled layer called fluting between flat liners, and the number of fluted layers decides how much weight and stacking the box can take. Pack Solution sells shipping cardboard boxes in one layer (single wall) and two layers (double wall), plus a crash lock style that folds up into shape with no tape on the bottom.
Because every box is sold flat, a pallet of cardboard shipping boxes takes up little room in a spare room or garage. You build them when an order comes in. That suits a seller who stocks six sizes and does not want finished boxes sitting around.
Single Wall Or Double Wall Cardboard Shipping Boxes?
Single wall suits light and medium orders. Double wall suits heavy, fragile or high value items that need a stiffer box.
Cardboard boxes for shipping come in two main grades. Single wall cardboard boxes are lightweight corrugated boxes for everyday e-commerce orders, storage and light moving. Double wall cardboard boxes are heavy duty, with two layers of fluting that give extra strength and better stacking. If you are unsure which board an item needs, the single wall vs double wall comparison sets out the differences in full.
| Box | Board | Sizes | Best for |
|---|---|---|---|
| Single Wall Cardboard Boxes | Single wall corrugated | 16 sizes, 5 x 5 x 5" to 24 x 18 x 18" | Everyday e-commerce orders, storage, light moving |
| Double Wall Cardboard Boxes | Double wall, two layers of fluting | 13 sizes, 7 x 5 x 5" to 24 x 24 x 24" | Heavier, fragile and high value items, house moves |
| Crash Lock Boxes | Cardboard, automatic locking base | 14 sizes, 100 x 100 x 70mm to 426 x 300 x 300mm | High volume packing, subscription boxes, retail products and samples |
Good to know: one single wall size, 15.35 x 11.6 x 7.3" (390 x 295 x 185mm), is listed as Extra Strong. It is a useful middle step when a standard single wall box feels light for the contents.
Crash Lock Boxes For Faster Packing
A crash lock box has an automatic base that locks as you open it, so it assembles in seconds and only the top needs taping. That saves both time and tape on every order.
Push the flat box open and the base folds and locks itself. For a seller packing dozens of parcels a day, skipping the bottom seam is a saving, and the finished box has a clean, retail-ready shape that suits products, samples and gift boxes. The smallest size, CL-A at 100 x 100 x 70mm, suits jewellery, small cosmetics and samples. CL-J at 426 x 300 x 150mm takes an A4 item (210 x 297mm) flat, and CL-K at 426 x 300 x 300mm is the deepest size.
Sellers on eBay, Etsy and Vinted often have boxes mailing out to customers every day, and speed matters most to them. If your parcels are mostly small and light, they can replace a mix of boxes and fill. If you send heavy or very fragile goods, double wall is the safer starting point.
How To Match The Box To The Product
Measure the item, add room for wrapping, and pick the next internal size up. A box that is too big costs more to post and lets the contents move.
All single wall sizes are internal measurements, length x width x height. For double wall, pick the smallest box that holds the item plus wrapping, and put heavy items in smaller boxes so they stay easy to lift. The table below pairs common items with box sizes taken from the product pages.
| Item | Box to look at | Size |
|---|---|---|
| Jewellery, small cosmetics, samples | Crash lock CL-A | 100 x 100 x 70mm |
| A5 item laid flat | Crash lock CL-F | 290 x 208 x 95mm |
| A4 item laid flat | Crash lock CL-J, or single wall | 426 x 300 x 150mm, or 12 x 9 x 4" to 12 x 9 x 9" |
| Candles, mugs, gifts | Single wall | 5 x 5 x 5" to 7 x 5 x 5" |
| Books, small electronics, accessories | Single wall | 8 x 6 x 4" to 10 x 8 x 6" |
| Homeware and stock | Single wall | 12 x 12 x 12" and 18 x 12 x 12" |
| Small, heavy parts | Double wall | 7 x 5 x 5" to 9 x 6 x 6" |
| Bulky but light items such as bedding | Double wall | 24 x 18 x 12" and up |
Most sellers end up with a short list of sizes that cover most of their range. Mailing boxes UK sellers reorder often cost less per box in bulk, because volume pricing applies on the product pages.
Large Shipping Boxes And Mailing Boxes Large Enough For Bulky Items
The largest single wall size is 24 x 18 x 18" (610 x 457 x 457mm), and the largest double wall size is 24 x 24 x 24" (610 x 610 x 610mm).
These shipping corrugated boxes suit homeware, bedding, stock moving between sites and removals. Check two things before you order. The double wall 24 x 24 x 24" size has a minimum order of 90 boxes, and the biggest sizes go on 2-day delivery only: the single wall 24 x 18 x 18" and the double wall 14 x 14 x 14", 18 x 18 x 18", 23 x 12 x 15", 24 x 18 x 12" and 24 x 18 x 18" sizes. For pallet orders of 100 or more boxes placed before 1pm, next-day pallet delivery to the UK mainland is possible, so call the team to arrange it.
If you are comparing mailing boxes large enough for a flat-packed product against a bag, remember that a rigid box protects corners and edges in a way a bag cannot. The cardboard boxes buying guide covers the wider range of box styles.
Sealing And Labelling Parcel Boxes
A tape gun seals boxes faster and neater than hand-cutting tape, and a thermal label printer removes handwriting from the process.
The tape gun is a pistol grip dispenser with a built-in cutting blade. There are four models: the PG50B, the heavy duty Pacplus HPG50B and the Big Tape 2in1 Core take 50mm tape, and the PG75B takes 75mm tape. Most packing tapes come in 48mm widths, so a 50mm model fits most rolls.
Best for sealing boxes with one hand
Pistol Grip Tape Gun Dispensers
A pistol grip dispenser with a built-in cutting blade, in four models for 50mm and 75mm tape.
- HPG50B, PG50B and Big Tape 2in1 Core take 50mm tape
- PG75B takes 75mm tape
- Sold individually
From £5.00 ex VAT (£6.00 inc VAT)
Choose sizeView productFor labels, the standard courier size is 4 x 6" (101.6 x 152.4mm). Fanfold labels come as a folded stack of 1000 rather than a roll, which means fewer reloads when you print all day. They are direct thermal, so the printer uses heat and you never buy ink, toner or ribbon. Check that your printer is a direct thermal model set to 4 x 6 inch labels before ordering.
Best for printing courier labels in volume
Fanfold Thermal Labels 4 x 6"
Direct thermal labels in a folded stack of 1000, so there is no ink, toner or ribbon to buy.
- 4 x 6" (101.6 x 152.4mm)
- 1000 labels per stack
- Self-adhesive and perforated at each fold
£12.00 ex VAT (£14.40 inc VAT)
Buy nowView productCost Per Order And Delivery
The cost of a box is only part of the cost per order. Wrapping, tape, labels and your own packing time all count, so a slightly dearer box that packs faster can work out cheaper.
The packaging cost per order guide shows how to add these up. Crash lock boxes cut tape use and packing time because the base needs no tape. Right-sized boxes reduce void fill. Volume pricing means the price per box falls as you buy more, with the tiers shown on each product page.
On the delivery side, orders placed by 2pm Monday to Friday are dispatched the same working day. Royal Mail Tracked 48 is free on every order with no minimum and usually arrives 2-3 working days after dispatch. Express and DPD options are available if you need it sooner. Details are on the shipping policy. Unused items can be returned within 30 days of delivery, which is set out in the refund policy.
Good to know: boxes are sold in a minimum of 5 per size, so a trial order of mixed sizes is a low-risk way to test what fits your range before you buy in bulk.
Parcel Box Checklist
- Measure the longest, widest and deepest point of the item, then add room for wrapping.
- Pick single wall for light orders and double wall for heavy, fragile or high value ones.
- Use crash lock boxes where speed matters and the contents are light.
- Check whether your size needs 2-day delivery before promising a date to a customer.
- Match the tape gun to your tape width: 50mm models for most rolls, the PG75B for 75mm.
- Print courier labels at 4 x 6" on a direct thermal printer.
- Store boxes flat and build them as orders arrive.
Wrap-Up
For most online shops, a few sizes of single wall boxes cover the everyday range, double wall covers the heavy and fragile orders, and crash lock boxes speed up the small, light ones. Pack Solution has them all in the boxes collection, with the tape guns and labels in equipment. If you are packing by hand for the first time, the step-by-step packing guide walks through the process from start to finish.
Frequently Asked Questions
Which parcel boxes suit most online orders?
Single wall cardboard boxes suit most everyday orders. Pack Solution sells them in 16 sizes from 5 x 5 x 5" to 24 x 18 x 18", flat packed with a minimum of 5 per size. Move to double wall for heavy, fragile or high value items, which have two layers of fluting.
Are mailing boxes the same as shipping boxes?
In practice the terms overlap. Both describe cardboard boxes used to send goods by post or courier. Pack Solution's single wall range includes a 450 x 350 x 160mm box made to the Royal Mail Small Parcel maximum size, which is the size many sellers look for when posting.
What size cardboard box for shipping an A4 item?
A4 (210 x 297mm) lies flat in the 305 x 229mm base of the single wall 12 x 9 x 4", 12 x 9 x 6" and 12 x 9 x 9" boxes. The crash lock CL-J, at 426 x 300 x 150mm, also takes an A4 item flat.
Do crash lock boxes need tape on the bottom?
No. The base locks automatically as you open the flat box, so you only tape the top. The 14 sizes run from 100 x 100 x 70mm to 426 x 300 x 300mm, with a minimum order of 5 boxes per size.
How long do large shipping boxes take to arrive?
The largest sizes go on 2-day delivery only. That covers the single wall 24 x 18 x 18" and the double wall 14 x 14 x 14", 18 x 18 x 18", 23 x 12 x 15", 24 x 18 x 12" and 24 x 18 x 18" sizes. Orders placed by 2pm Monday to Friday are dispatched the same working day.
What size label goes on parcel boxes?
The standard courier label is 4 x 6" (101.6 x 152.4mm). Pack Solution's fanfold thermal labels come in that size as a stack of 1000, for direct thermal printers that need no ink or ribbon.
