4x6 Thermal Labels: Size in mm and cm, Rolls vs Fanfold, and Printer Setup

4x6 thermal labels measure 4 x 6 inches, which is exactly 101.6 x 152.4mm, or 10.16 x 15.24cm. Most suppliers round that to 100 x 150mm (10 x 15cm), and the two figures describe the same courier label. So if you need the 4x6 label in mm for a printer setting or a label tool, enter 101.6 x 152.4mm, or 100 x 150mm if that is the closest option offered. The size is the standard for UK courier and marketplace shipping labels, and it prints on direct thermal printers with no ink.

This guide covers the exact size in mm, cm and inches, why the same label is also sold as 6x4, the choice between rolls and fanfold stacks, how to set your printer page size, and which bags and boxes give the label a flat face to sit on.

Quick picks: 4x6 thermal labels and what they go on

Two ways to buy the label, and the two most common things it is stuck to.

Best for printing courier labels all day

Fanfold Thermal Labels 4 x 6"

A folded stack of 1000 direct thermal 4 x 6 inch labels, perforated between each label.

• 101.6 x 152.4mm courier size
• 1000 labels per stack
• No ink, toner or ribbon

£12.00 ex VAT (£14.40 inc VAT)

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Best for printers that take a roll inside the cover

Thermal Labels on Rolls

Self-adhesive direct thermal labels on rolls, with the 4 x 6" courier size at 500 per roll.

• 4 x 6" (100 x 150mm), 500 per roll
• Also 2 x 1", 3 x 2", 4 x 4" and 4 x 8"
• Price per roll falls as you buy more

From £3.50 ex VAT (£4.20 inc VAT)

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Best for clothing and soft goods

Grey Mailing Bags

Opaque, self-seal polythene mailers with a water resistant outer and a flat face for the label.

• 16 sizes, 4 x 6" to 34 x 42"
• Packs of 100, 50 or 25 by size
• No tape needed

From £2.90 ex VAT (£3.48 inc VAT)

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What size is a 4x6 label in mm, cm and inches?

The 4 x 6 label in mm is 101.6 x 152.4mm, because an inch is exactly 25.4mm. Suppliers often list it as 100 x 150mm, which is a rounded figure, so a label sold as either size is the same courier label in practice. Our fanfold stacks are listed at 101.6 x 152.4mm and our 4 x 6 inch rolls at 100 x 150mm.

The 4x6 label in cm is 10.16 x 15.24cm, which most printer drivers and label tools round to 10 x 15cm. If a setting asks for millimetres and only accepts whole numbers, 102 x 152mm or 100 x 150mm both work on a printer set up for 4 x 6 inch stock.

For comparison, our other thermal roll sizes are 2 x 1" (50 x 25mm), 3 x 2" (76 x 51mm), 4 x 4" (101.6 x 101.6mm) and 4 x 8" (100 x 210mm). The 4 x 8" label is the same width with room for a packing slip below the address. Our guide to thermal label sizes covers all five in more detail.

Are 4x6 and 6x4 labels the same?

Yes. 6x4 thermal labels and 4x6 labels are the same 101.6 x 152.4mm label. The order of the numbers usually reflects how the maker describes width and length. Most thermal printers feed the label short edge first, so it comes out 4 inches wide and 6 inches long, and that is why 4 x 6 is the more common name. Royal Mail and several marketplaces label the same format as 6 x 4.

The name only matters in two places. In a courier or marketplace label tool, pick whichever of 4 x 6 or 6 x 4 it lists, since both mean the same size. In your printer settings, make sure the page is set to portrait, 4 inches wide by 6 inches high, so the label prints the right way up and fills the face.

Do not confuse these with sheet labels. Products sold as 6x4 labels A4 are sheets of paper labels for an inkjet or laser printer. They are a different product, and a thermal printer cannot print on them.

Rolls or fanfold stacks: which suits your printer?

4x6 shipping labels come in two formats. A roll is wound on a core, and a fanfold stack is a long strip folded back and forth at the perforations. The labels are the same; the difference is how they feed into the printer and how often you reload.

Choose a 4 x 6 labels roll if your printer has a roll holder under the lid and no rear feed slot, or if the bench has no space behind the printer. Our Thermal Labels on Rolls come at 500 per 4 x 6 inch roll and suit Zebra-style direct thermal printers that take standard rolls. Before you order, check the roll width your printer accepts and the core it takes, as some compact desktop printers have a small roll bay and printers that only accept their own branded rolls will not take them.

Choose fanfold labels if your printer has a feed slot at the back or underneath, which most 4 x 6 desktop direct thermal labels printers do. Fanfold Thermal Labels 4 x 6" hold 1000 labels per stack, twice a roll, so you reload half as often. The stack sits flat behind the printer, there is no core to fit, and each label tears off cleanly at the perforation.

Most desktop printers will run either format. In practice, sellers posting a handful of parcels a day tend to use rolls, and anyone printing direct thermal fanfold labels by the hundred each week moves to stacks because reloading less often saves time at the bench. Our guide to choosing shipping labels: rolls, fanfold or A4 sheets compares all three formats side by side.

What does direct thermal mean for 4x6 labels?

Direct thermal labels have a heat-sensitive coating. The print head heats tiny points on the label face and those points turn black. There is no ink cartridge, toner or ribbon to buy, so the only running cost is the labels themselves.

That makes 4x6 thermal printing simple to run. Load the labels, print, peel and stick. The labels are self-adhesive, so each one goes straight onto the bag or box. Barcodes print crisp and scan cleanly, which is what couriers need at the depot.

A few habits keep the print readable until the parcel is delivered:

• Store spare stacks and rolls in their packaging, away from direct sunlight and radiators, since heat is what marks the label.
• Do not leave printed labels on a sunny windowsill or a warm van dashboard for days before posting.
• Keep the label away from solvents and hand sanitiser when you stick it down.
• Clean the print head now and then as the printer maker advises, so barcodes stay sharp.

Which couriers and marketplaces print 4x6 shipping labels?

4 x 6 inches is the usual courier label size in the UK. Royal Mail, Evri, DPD and InPost label tools generally offer a 4 x 6 or 6 x 4 format, and eBay, Etsy and Vinted sellers can print order labels at that size too. The exact menu wording differs from one service to the next, and it can change, so check the label or print settings in your account before your first print run.

What to look for in each tool:

1. A label format or paper size setting with a 4 x 6, 6 x 4 or thermal option.
2. A choice between PDF and a printer-ready format. A PDF at 4 x 6 size is the simplest place to start.
3. An option to print one label per page, not two or four labels on an A4 sheet.

If the tool only produces A4, it will shrink the label to fit a thermal page, and the barcode may be too small to scan. Look for the 4 x 6 option first. Our guide on how to print Royal Mail labels at home walks through the Royal Mail settings step by step.

How do you set the printer page size for 4x6 labels?

Most print problems with 4x6 shipping labels come from the page size, not the labels. Set it once and every label after that prints full size.

1. Add a paper size of 4 x 6 inches. In the printer driver or preferences, create or select a stock of 4 x 6 in (101.6 x 152.4mm). If the driver uses metric, 100 x 150mm also works.
2. Set portrait orientation. Width 4 inches, height 6 inches. Landscape prints the label sideways and cuts it off.
3. Print at actual size. In the print dialog, choose 100% or actual size, not fit to page or shrink to fit.
4. Choose direct thermal mode. If the driver asks for a print method, pick direct thermal, not thermal transfer, since these labels use no ribbon.
5. Calibrate after loading. Run the printer's label calibration when you change stock, so it finds the gap between labels and stops on each one.
6. Print one test label. Check the barcode is sharp and the address sits fully inside the edges before you print a batch.

Which bags and boxes fit a 4x6 label?

The label needs a flat face at least 101.6 x 152.4mm, with a little margin so it does not wrap round an edge or sit over a seam. That rules out some of the smallest packaging.

Mailing bags. Grey Mailing Bags are opaque, self-seal and water resistant, and the flat front takes a 4x6 label easily from the 6 x 9" (165 x 230mm) size up. The smallest 4 x 6" (100 x 150mm) bag is about the same size as the label itself, so it suits small accessories where you would print a smaller label. For clothing, 10 x 14" to 14 x 21" are the usual sizes. More colours are in the mailing bags collection.

Boxes. Single Wall Cardboard Boxes run from 5 x 5 x 5" (127 x 127 x 127mm) to 24 x 18 x 18" (610 x 457 x 457mm), sold per box with a minimum of 5 per size. A 6 inch label will not lie flat on the top of a 5 x 5 x 5" box, and it is a tight fit on 6 x 6 x 6". From 8 x 6 x 4" (203 x 152 x 102mm) up, the top face takes the label comfortably. The 17.7 x 13.7 x 6" (450 x 350 x 160mm) box is the Royal Mail Small Parcel maximum size.

Best for everyday parcels that need a box

Single Wall Cardboard Boxes

Light corrugated boxes supplied flat, sold per box with a minimum of 5 per size.

• 5 x 5 x 5" up to 24 x 18 x 18"
• Includes the 450 x 350 x 160mm Royal Mail Small Parcel max size
• Price per box falls as you buy more

From £0.35 ex VAT (£0.42 inc VAT)

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Wherever it goes, stick the label on the largest flat face, smooth it from the centre outwards, and keep it clear of tape joins and box seams so it scans first time.

How many 4x6 thermal labels should you order?

Work from how many parcels you send in a normal week, then add a margin for busy periods and the odd misprint.

Keep at least one spare roll or stack on the shelf so you never stop printing in the middle of a dispatch run. Prices are shown ex VAT, and the price per roll or per stack drops as you order more, with the tiers on each product page. Our 4 x 6 thermal roll labels and stacks are sold singly, so you can start with one of each to see which feeds better in your printer.

Order fanfold 4x6 labels

Ordering your labels

If your printer takes a roll inside the cover, order 4x6 shipping labels roll stock from the rolls page and pick the 4 x 6" size. If it feeds from behind, fanfold shipping labels in stacks of 1000 will save reloads. Other sizes and sheet labels are in the labels collection.

Orders placed by 2pm Monday to Friday are dispatched the same working day, and Royal Mail Tracked 48 is free on every order with no minimum. In Manchester, you can collect free from Unit 2, 50 Derby Street, or check the local delivery page for same-day van delivery. Businesses that order labels every week can apply for a trade account, or contact us about regular quantities.

Choose your thermal label rolls

Frequently Asked Questions

What size is a 4x6 label in mm?

A 4 x 6 inch label is 101.6 x 152.4mm. Many suppliers round it to 100 x 150mm, and our 4 x 6" rolls are listed at that size. Both fit a printer set up for 4 x 6 inch labels.

Are 4x6 and 6x4 thermal labels the same?

Yes. 4x6 and 6x4 describe the same 101.6 x 152.4mm label. The first number is usually the width as it comes out of the printer, but courier and marketplace label tools use both names for the same format.

Do 4x6 thermal labels need ink?

No. They are direct thermal labels, so the printer marks them with heat. There is no ink, toner or ribbon to buy.

Should I buy rolls or fanfold stacks?

Fanfold stacks of 1000 suit printers that can feed from behind or below and sellers who print all day. Rolls of 500 suit printers that only take a roll inside the cover, or benches with little space.

Can I print Royal Mail, Evri or Vinted labels on 4x6 thermal labels?

Yes, as long as the carrier or marketplace label tool offers a 4 x 6 (or 6 x 4) format and you print on a direct thermal printer. Choose that format in the label settings before you print.

Do you sell label printers?

No. We sell the labels, not the printers. Our 4 x 6 labels suit Zebra-style direct thermal printers that take standard rolls; printers that only accept their own branded rolls will not take them.

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Related Guides

• Thermal Labels Explained: Sizes, Rolls, Storage and Royal Mail Labels
• Shipping Labels: Thermal Rolls vs Fanfold vs A4 Sheets
• Royal Mail Print Label Guide: Thermal Labels or A4 Sheets at Home

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