What Is Mailmark? A Guide for Franking Machine Users

Mailmark is Royal Mail's smart franking format, a machine-readable 2D barcode that replaces the old town-and-crown die and unlocks the lowest available postage prices for franking machine users. If you run a modern franking machine, sending mail on Mailmark means cheaper postage, automatic tariff updates and no annual machine inspections. In 2026 it is the standard every business franking its own post should be using, and this guide explains what it is, why it saves money and what you need to do.

What is Mailmark franking?

Mailmark is the latest generation of the franking impression printed onto your envelope or franking label. Instead of the traditional round crown die, a Mailmark frank carries a 2D data-matrix barcode that holds machine-readable information about the sender and the mail item. Royal Mail scans that barcode as your post travels through its network, which lets it process franked mail more accurately and reward franking customers with reduced prices. You can read the official overview on the Royal Mail franking pages.

Every franking machine sold today is a Mailmark machine. Older analogue and digital meters that only print the legacy indicia have gradually been withdrawn from service, so Mailmark is now the mainstream way UK businesses frank their own mail.

How the Mailmark frank looks

A Mailmark impression is cleaner and more professional than the old-style frank. It includes the 2D barcode, your postage value, the class of service, the date and a supporting royal crown. Because the barcode is the part Royal Mail's automated equipment reads, a crisp, complete print matters. A faded or streaky impression can cause a scan to fail, which is exactly why it pays to keep your machine topped up with good franking ink and labels. If your prints ever look patchy, our guide on why a franking machine prints faded walks through the usual causes and fixes.

Why Mailmark saves you money

The headline reason to use Mailmark is price. Royal Mail deliberately prices Mailmark franking below the equivalent stamp, so you pay less for the same delivery. As of the tariff that took effect on 7 April 2026, a 1st Class letter up to 100g costs £1.80 with a stamp but only £1.77 on Mailmark franking, and a 2nd Class letter costs 91p with a stamp against 88p franked. That is a 3p saving on every single letter.

The savings grow with larger formats. A 1st Class Large Letter up to 100g is £3.30 by stamp but £2.86 on Mailmark franking, a saving of 44p per item. Over a year of steady mailing, those differences add up quickly, which is the core argument in our comparison of franking versus stamps in 2026. Standard Royal Mail retail postage is exempt from VAT, so the prices you see are the prices you pay.

The main benefits of Mailmark

Lower postage is the biggest draw, but Mailmark bundles several other advantages that make day-to-day franking simpler:

• The lowest franking prices. Mailmark rates sit below both stamps and older franking formats.
• No postcode restriction. Unlike some legacy franking, Mailmark lets you post from anywhere without being tied to a registered posting location.
• Automatic tariff updates. When Royal Mail changes its prices, Mailmark machines can update their rates automatically so you are always franking at the correct value.
• No annual inspections. Mailmark meters are not subject to the yearly Royal Mail inspection that older machines required.
• Prepaid reply mail. Mailmark supports printing prepaid reply envelopes, which is useful if you send response-paid post to customers.

The King's Crown update coming in April 2026

One change every franking user should be aware of is the updated royal crown shown within the indicia. Royal Mail has asked manufacturers to update the crown printed by franking meters in line with current guidelines, and this update takes effect from April 2026. Any brand new machine is delivered with the updated crown already applied, and existing Mailmark machines receive the change automatically through a software update in the run-up to the deadline. For most customers no action is needed; your machine simply updates itself. If you are ever unsure whether your meter is current, Royal Mail's guide on how to prepare and post franked mail is a helpful reference.

Do you need to do anything to use Mailmark?

If you already have a modern franking machine, you are almost certainly franking on Mailmark already and no action is required. Your machine downloads rate changes and crown updates over its network connection, so your job is simply to keep it stocked with postage credit and consumables. That means having the right ink cartridge for your model on hand and a supply of compatible franking labels for parcels and post that will not go through the machine directly.

If you are running an older meter that only prints the legacy frank, it is worth checking whether it is still certified for use, because non-Mailmark machines miss out on the cheapest prices and several of the conveniences above.

Keeping your Mailmark frank clean and scannable

Because Royal Mail's equipment reads the Mailmark barcode automatically, print quality is not just cosmetic; it affects whether your mail is processed smoothly. Use genuine or approved-quality ink, replace cartridges before they run dry and store them correctly. Choosing between original and compatible franking ink is a common question, and the right answer keeps your barcode sharp without overspending. Clean, well-sealed envelopes help too, so it is worth stocking quality franking envelopes and, where relevant, self seal envelopes that feed cleanly through your machine.

Frequently asked questions

What does Mailmark mean on a franking machine?

Mailmark is Royal Mail's current franking format. It prints a machine-readable 2D barcode instead of the old crown die, which lets Royal Mail process franked mail automatically and offer franking customers the lowest postage prices.

Is Mailmark franking cheaper than stamps?

Yes. Royal Mail prices Mailmark franking below the equivalent stamp. From 7 April 2026, for example, a 1st Class letter is £1.77 franked against £1.80 by stamp, and a 2nd Class letter is 88p franked against 91p by stamp, with much larger savings on Large Letters.

Do I need to do anything for the April 2026 crown update?

For most users, no. New machines ship with the updated crown, and existing Mailmark machines receive it automatically through a software update before the April 2026 deadline, so there is normally nothing you need to do.

Does a Mailmark machine still need an annual inspection?

No. One of the benefits of Mailmark is that these machines are not subject to the annual Royal Mail inspection that older franking meters required.

Why does my Mailmark frank need to be clear?

Royal Mail scans the Mailmark barcode automatically, so a faded or incomplete print can cause a scan to fail. Keeping your machine supplied with good ink and clean labels ensures your mail is processed without issues.

Ready to keep your Mailmark franking running smoothly? Browse the correct cartridges and labels for your machine at Franking Ink, or get in touch with our team if you need help finding the right supplies for your model.