If your franking machine is printing faded, faint or patchy marks, the usual causes are a low or dried-out ink cartridge, a dirty print head, the wrong ink for your machine, or a cartridge that has been left exposed to air. In most cases the fix is simple: run the machine's cleaning cycle, check the ink level, and fit a fresh, Royal Mail approved cartridge made for your exact model. Getting this right matters because Royal Mail requires every franked impression to be clear and legible, and faint marks can lead to mail being delayed or returned.
At Franking Ink we speak to businesses every week who are frustrated by streaky postage marks just as a deadline approaches. The good news is that faded franking is almost always preventable. This guide walks through why it happens, how to fix it quickly, and how to keep your impressions sharp for the long term.
What a good franking impression should look like
A correct franking mark is solid, evenly inked and complete, with no missing lines or pale streaks. It should sit in the top right-hand corner of the envelope and show all the required detail, including the postage value, date and your licence number. Modern Mailmark machines also print a 2D barcode that Royal Mail's sorting equipment scans automatically, so any fading across that barcode can stop your mail being read correctly.
Crucially, the ink colour is part of compliance. Mailmark and smart franking machines must use Royal Mail approved blue ink, while older digital machines use approved red ink. Approved ink is tested to make sure Royal Mail's automated systems can recognise and sort your mail, so using the correct cartridge is not just about looks.
Common causes of faded franking marks
1. The ink cartridge is low or empty
This is the most frequent culprit. Franking cartridges hold a finite number of impressions, and print quality tails off as they run dry. Most machines display a low-ink warning, but heavy mailroom use can empty a cartridge faster than expected. Keeping a spare cartridge on the shelf is the easiest way to avoid being caught out, and our model-specific franking ink and label collections make it simple to reorder the right one.
2. A blocked or dried print head
Franking machines use inkjet technology, and the tiny nozzles can clog if the machine sits unused for a while or if the ink has begun to dry. Dried nozzles produce horizontal white lines or patchy coverage. Running the built-in head-cleaning routine usually clears this. If you are unsure where to find it, Royal Mail's franking troubleshooting guide and your machine manual both explain the cleaning process.
3. The wrong or non-approved ink
Fitting a cartridge that is not designed for your model, or that is not Royal Mail approved, can cause poor adhesion, the wrong colour density and rejected mail. Always match the cartridge to your machine. If you are switching suppliers, double-check the model number on your machine against the product before ordering.
4. Ink exposed to air or stored badly
Once a cartridge is unsealed, the ink can dry around the nozzles if it is left out of the machine or stored in a hot, dry spot. Keep spare cartridges in their sealed packaging, away from direct heat, until you need them. A cartridge that has been open and idle for weeks may never print cleanly again.
5. Damp, glossy or coloured envelopes
The surface you frank onto matters too. Very glossy or heavily coloured envelopes can stop ink absorbing properly, leading to smudged or faint marks. Where the envelope is the wrong size, shape or colour, the simplest solution is to frank onto a label instead. Our universal double sheet franking labels and machine-specific options such as Pitney Bowes franking labels give a clean, absorbent surface every time.
How to fix faded franking, step by step
- Check the ink level. Use the machine menu to confirm how much ink remains. If it is low, fit a fresh cartridge.
- Run the print-head cleaning cycle. Most machines have a one-touch clean function. Run it once or twice and test on a scrap envelope.
- Reseat the cartridge. Remove the cartridge, check the nozzles are not visibly dry, gently wipe any build-up with a lint-free cloth, then refit it firmly.
- Confirm you are using approved ink. Make sure the cartridge is the correct colour and model for your machine.
- Test on a clean envelope or label. Frank a test impression and check it is solid and complete before running your full batch.
If the mark is still faint after a fresh cartridge and a clean, the issue may be the print head itself, and it is worth contacting your machine manufacturer or our team.
How to prevent faded marks in future
Prevention comes down to good habits. Keep at least one spare cartridge in stock, store it sealed and cool, and run a short test print if the machine has been idle for several days. Order genuine or quality compatible ink that is matched to your model, and replace cartridges before they run completely dry rather than squeezing out the last few impressions. Franking onto labels for awkward items keeps every mark crisp and compliant.
Buying ahead also protects you from downtime. Because franking ink is consumable and demand is constant, running out mid-batch can hold up an entire day's post. You can check our delivery information for current dispatch times so a spare always arrives before you need it.
Why clear impressions are worth the effort
A faded franking mark is more than an aesthetic problem. Royal Mail's automated equipment needs to read the value and barcode to process your post, and items that cannot be read may be delayed, surcharged or returned. Sharp, correctly coloured impressions keep your mail moving and protect your business reputation with customers who are waiting on it.
Frequently asked questions
Why is my franking machine printing faint lines through the mark?
Horizontal white lines usually mean the print head nozzles are partly blocked or drying. Run the cleaning cycle, and if that does not work, fit a fresh cartridge. Persistent lines after both steps point to a print head that needs servicing.
What colour ink should my franking machine use?
Mailmark and smart machines use Royal Mail approved blue ink, while older digital franking machines use approved red ink. Using the correct, approved colour ensures Royal Mail's systems can scan and sort your mail.
How many impressions does a franking cartridge last?
It varies by machine and cartridge size, from a few thousand to tens of thousands of impressions. Your machine tracks usage and shows a low-ink warning, so keep a spare ready before the warning appears.
Can I just frank onto a label instead of the envelope?
Yes. Royal Mail allows franking labels for envelopes and packets of different sizes, shapes and colours, and they are ideal when an item is too thick or glossy to frank directly. Make sure you use labels approved for franking.
Where can I buy the right ink for my machine?
Browse the Franking Ink store by your machine model to find matched cartridges and labels, or contact our team if you are not sure which cartridge fits your machine.
Need ink today? Find your machine model in our franking ink and labels range and order a fresh cartridge so your next batch of post goes out crisp, clear and Royal Mail ready.