Short answer: if you print shipping labels every day, a direct thermal label printer with 4 x 6 inch labels is usually the most practical setup: no ink or toner, and one label per parcel. Choose rolls if your printer holds labels inside its cover or desk space is tight, and fanfold stacks if you print long runs and have room for a stack behind or below the printer. If you post only a few parcels a week and already have an office printer, A4 sheet labels are a simple way to start without buying another machine.
Before you order anything, check three things: that your printer is the right type (direct thermal for thermal labels), that it accepts the label width and format you plan to buy, and that it fits the roll or stack dimensions. This guide explains each choice, the checks that avoid wasted labels, and how to set up and troubleshoot a simple label workflow.
Contents
- Thermal labels or sheet labels?
- How direct thermal labels work
- Rolls or fanfold?
- Label sizes and what they are for
- Printer compatibility checklist
- Setting up a label workflow
- Troubleshooting print problems
- Working out cost per label
- Common mistakes
- Questions buyers ask
Thermal labels or sheet labels?
There are two broad routes to printing shipping labels.
A dedicated thermal label printer prints one label at a time onto self-adhesive labels on a roll or fanfold stack. Most courier and marketplace label tools can output a 4 x 6 inch label, and the printer produces it in seconds with no ink. For anyone posting several parcels a day, this is usually faster and tidier.
An office printer with A4 sheet labels prints onto sheets of self-adhesive labels. It uses the inkjet or laser printer you already have. The downsides are ink or toner cost, partly used sheets if you print one label at a time, and slower handling. The upside is no extra hardware and flexibility: the same sheets can print address labels, product labels and returns labels.
| Factor | Thermal labels (roll or fanfold) | A4 sheet labels |
|---|---|---|
| Printer needed | Direct thermal label printer | Office inkjet or laser printer |
| Ink, toner or ribbon | None for direct thermal | Ink or toner |
| Best for | Daily shipping, one label per parcel | Low volume, mixed label uses |
| Speed per label | Fast, label by label | Slower; sheet handling |
| Waste | Low if printer is set up correctly | Partly used sheets unless batched |
| Label durability | Can darken with heat and light (see below) | Depends on printer and label |
How direct thermal labels work
A direct thermal label has a heat-sensitive coating. The printer's printhead heats tiny points on the label, which darken to form text and barcodes. There is no ink and no ribbon. Zebra, a major thermal printer maker, describes direct thermal printing as using "chemically treated, heat-sensitive media" and lists shipping labels and receipts as ideal applications in its explanation of direct thermal and thermal transfer printing.
The alternative, thermal transfer, uses a heated ribbon to transfer ink onto the label. It produces longer-lasting labels and is used where labels must survive for years or in harsh conditions. It needs ribbons and compatible labels.
The key limitation of direct thermal is durability. Zebra notes that if the label is overexposed to heat, light or other catalysts, the material will darken. For a shipping label that only needs to last until the parcel is delivered, that is rarely a problem. For product labels that sit in sunlight or near heat for months, it can be. Store unused direct thermal labels somewhere cool, dry and out of direct sunlight.
All the thermal labels Pack Solution currently stocks are direct thermal, so they need a printer that supports direct thermal printing, set to direct thermal mode.
Rolls or fanfold?
Both formats carry the same kind of labels. The difference is how they are supplied to the printer.
Thermal labels on rolls
Labels are wound on a core. Many desktop label printers hold a roll inside the printer under a cover. Rolls are compact and keep labels clean. Their limitation is capacity: a roll can only be as large as the printer's roll holder allows, so busy benches change rolls more often.
Our thermal labels on rolls are self-adhesive direct thermal labels in five sizes, sold by the roll:
| Label size | Labels per roll | Typical use |
|---|---|---|
| 2 x 1" (50 x 25mm) | 1000 | Barcodes, stock codes, price labels |
| 3 x 2" (76 x 51mm) | 1000 | Product, shelf and bin labels |
| 4 x 4" (101.6 x 101.6mm) | 750 | Small parcels, warehouse and pallet ID |
| 4 x 6" (100 x 150mm) | 500 | Standard courier shipping labels |
| 4 x 8" (100 x 210mm) | 200 | Courier label with a packing-slip area |
Fanfold labels
Fanfold labels are folded into a flat stack rather than wound on a core. The stack sits behind or below the printer and feeds in through a rear or bottom slot. Because the stack is outside the printer, it can hold many more labels, which means fewer reloads.
Our 4 x 6" fanfold thermal labels (101.6 x 152.4mm) come in stacks of 1000, perforated between each label for a clean tear. That is twice the number of labels on our 4 x 6" roll.
Which format to choose
- Choose rolls if your printer only takes labels inside its cover, if you have little desk space, or if you print modest volumes.
- Choose fanfold if your printer has a rear or bottom feed slot, you print long runs, and you have space for the stack where it will not be knocked or get dusty.
Label sizes and what they are for
The 4 x 6 inch label is the common size for parcel shipping labels in the UK. Note that 4 x 6 inches is 101.6 x 152.4mm; you will often see it listed as 100 x 150mm, which is the rounded metric equivalent. Most label printing software lets you choose either; select the setting that matches your labels.
The 4 x 8 inch label is longer, with space for a packing slip or extra information below the address. It is useful if your sales channel can print the address and order details on one label. Check that your printer and software support the length before ordering.
Smaller labels are for products and stock rather than shipping. Use 2 x 1 inch or 3 x 2 inch for barcodes, stock codes, shelf and bin labels, and 4 x 4 inch for small parcels, cartons and pallet identification.
A4 sheet label layouts
Our A4 sheet labels come in 10 layouts, in boxes of 500 sheets:
| Labels per sheet | Label size | Common use |
|---|---|---|
| 1 | 199.6 x 289.1mm | Full-sheet shipping labels, large box labels |
| 2 | 199.6 x 143.5mm | Two shipping labels per sheet |
| 4 | 99.1 x 139.0mm | Parcel labels with room for a logo |
| 8 and 10 | 99.1 x 67.7mm / 57.3mm | Addresses on mailing bags and envelopes |
| 21, 24, 27 | About 63.5 x 38.1 / 33.9 / 29.6mm | Address and return address labels |
| 44 and 65 | 48.5 x 25.4mm / 38.1 x 21.2mm | Small product, price and barcode labels |
If your courier tool prints a 4 x 6 inch label on A4 paper, the 2-per-sheet or 4-per-sheet layouts are worth comparing with the label artwork; the label must not be shrunk so much that the barcode becomes hard to scan. Print a test page on plain paper first and hold it over a label sheet to check alignment.
Printer compatibility checklist
Most label problems are compatibility problems. Work through this list before ordering a large quantity.
- Printer type. Is it a direct thermal printer, a thermal transfer printer that can also run in direct thermal mode, or an office printer? Thermal labels need a thermal printer set to direct thermal mode.
- Maximum label width. A 4 inch printer can print 4 inch wide labels. Check that the label plus its backing fits the printer's width.
- Roll dimensions. For rolls, check the core size the printer accepts and the maximum outer roll diameter. A roll that is too wide for the holder will not fit even if the label width is right. Our roll listing describes compatibility with "Zebra-style direct thermal printers that take standard rolls"; if your printer is a different design, or you are unsure about core size, contact us before ordering in bulk.
- Fanfold feed. For fanfold, check the printer has a rear or bottom feed slot and space for the stack.
- Label gap or perforation sensing. Thermal printers detect the gap between labels to start each print in the right place. After loading new labels, run the printer's calibration routine.
- Software settings. Set the label size, orientation and print density in the printer driver or the courier tool to match the labels.
Setting up a label workflow
The label itself is only part of the job. A tidy workflow prevents the most common dispatch errors: the wrong label on the wrong parcel, and labels that will not scan.
Print in order, pack in order
Print labels in the same order as your pick list, and pack in that order. When a label comes off the printer, it should go straight onto the parcel it belongs to. Printing a whole day's labels in one batch and matching them up later is where mix-ups happen, particularly when several orders contain similar items.
Use the packing-slip area if you have one
If your sales channel can print the order contents below the address, a 4 x 8 inch label carries both on one sticker. That means one print instead of two and no separate slip to match up, at the cost of a longer label and fewer labels per roll (200 on our 4 x 8" roll, against 500 on the 4 x 6").
Keep a test routine
Each time you load a new roll or stack, print one test label and scan the barcode with a phone app or the scanner you use. A quick check catches a wrong size setting or low print density before a full day's labels are affected.
Place labels where they scan
Stick labels flat on the largest face of the parcel, away from seams, edges and folds. On mailing bags, press from the centre outwards so no air bubbles lift the barcode. Do not cover any part of the barcode with tape; if you need to protect a label from rain, use clear tape over the address area only, or a documents enclosed wallet.
Plan label stock
Work out how many labels you use per day and keep enough for at least a week, plus a spare roll or stack. Running out of labels stops dispatch just as surely as running out of boxes.
Troubleshooting print problems
| Problem | Likely cause | What to try |
|---|---|---|
| Labels come out blank | Labels loaded upside down, or printer set to thermal transfer mode | Check which side is the printable side and set the printer to direct thermal mode |
| Print starts across the gap between labels | Printer not calibrated for the new labels | Run the calibration or label-sensing routine |
| Barcode cut off or shrunk | Wrong label size in software or driver | Set the size to 4 x 6 inch (or 100 x 150mm) to match the labels |
| Faint print | Print density or speed setting too low, or dirty printhead | Increase density slightly, slow the print speed, clean the printhead as the maker advises |
| Labels darken before use | Stored in heat or sunlight | Store rolls and stacks in a cool, dry, dark place |
| Roll does not fit | Core size or outer diameter does not match the printer | Check the printer's roll specifications before reordering |
A quick way to confirm whether a label is direct thermal, described by Zebra, is to scratch the surface firmly with a fingernail: direct thermal labels usually show a dark mark from the friction heat. If you see no mark, the labels may need a ribbon.
Working out cost per label
Compare label options on cost per label rather than cost per pack. The formula is simple:
Cost per label = price per pack (ex VAT) / number of labels in the pack
For A4 sheets, include ink or toner and any wasted labels:
Cost per label = (price per box / labels per box) + ink or toner cost per label + allowance for wasted labels
Illustrative example (assumed round figures, not our prices): one pack costs £10.00 and contains 1000 labels. Cost per label = £10.00 / 1000 = £0.010, which is 1p per label. Another pack costs £8.00 for 500 labels: £8.00 / 500 = £0.016, or 1.6p per label. On these assumptions the first option is cheaper per label even though its pack price is higher. Check current prices on the product pages, which show volume pricing tiers where available.
Cost is not the only factor. A format that suits your printer and reduces reloads and misprints can save more time than a small difference in label price.
Common mistakes
- Buying thermal labels for an office printer. Direct thermal labels are not designed for inkjet or laser printers.
- Not calibrating after loading. Skipping calibration causes labels to print across the gap.
- Wrong size setting. Printing a 4 x 6 label with the driver set to another size shrinks or cuts off the barcode.
- Storing labels in heat or sunlight. Direct thermal labels can darken before use.
- Labels on curved or creased surfaces. Apply to a flat panel so the barcode scans reliably.
- Ordering bulk before testing. Order one pack, test it in your printer, then scale up.
Other labels worth having
Beyond address labels, two simple additions help on a packing bench. Warning labels include Fragile labels at 89 x 32mm (1000 per roll) and Caution Heavy labels at 148 x 50mm (500 per roll). Documents enclosed wallets attach paperwork such as invoices to the outside of a parcel in a clear pouch.
Questions buyers ask
What size are 4 x 6 shipping labels in millimetres?
4 x 6 inches is 101.6 x 152.4mm, often rounded to 100 x 150mm in listings.
Do thermal labels need ink?
Direct thermal labels do not need ink, toner or ribbon. The printer uses heat to darken the label's coating.
How long do direct thermal labels last?
Long enough for most shipping purposes, but they can darken or fade with heat, light and some chemicals. For labels that must last years, thermal transfer labels with a ribbon are the usual choice.
Will your labels fit my printer?
Our thermal rolls are listed for Zebra-style direct thermal printers that take standard rolls. Check your printer's label width, roll core and maximum roll size, or contact us with your printer model before ordering in bulk.
Is fanfold cheaper than rolls?
Compare cost per label using current prices. Fanfold's main advantage is capacity: our 4 x 6 fanfold stack holds 1000 labels compared with 500 on our 4 x 6 roll.
Can I print courier labels on A4 sheets?
Yes, many courier tools offer A4 output. A 1, 2 or 4-per-sheet layout is usually the closest match. Check the barcode prints at a size the courier can scan.
Should I choose 4 x 6 or 4 x 8 labels?
Choose 4 x 6 if your courier and marketplace tools print a standard shipping label and you put the packing slip inside the parcel. Choose 4 x 8 only if your software prints the address and order details together on the longer label and your printer supports that length. Most sellers start with 4 x 6 because it is the common format.
How many labels should I keep in stock?
At least a week's usage plus a spare roll or stack. At 40 parcels a day, for example, a 500-label roll lasts about 12 working days, so keeping two rolls means you can reorder when the first is used without risking a gap.
Summary
For daily shipping, use a direct thermal printer with 4 x 6 inch labels: rolls for compact setups, fanfold for long runs. For low volumes and mixed label needs, A4 sheet labels on an office printer are a simple start. Check printer type, width, roll or stack fit and software settings before ordering in bulk, print and pack in the same order, test after every reload, compare on cost per label, and store labels away from heat and sunlight.
