Franking Machine Not Printing Properly? Causes and Fixes
If your franking machine is printing faint, streaky or incomplete impressions, the cause is almost always a blocked or dried-out printhead, a low or empty ink cartridge, or a cartridge that is not seated correctly. Running the machine's cleaning cycle, checking the ink level and reseating the cartridge will resolve the vast majority of print-quality problems. This matters because a clear, complete impression is not just tidy, it is what allows Royal Mail's sorting equipment to read your mail and accept the postage you have paid for.
Why franking print quality matters
A franking impression is proof of payment. When Royal Mail receives your mail, automated equipment reads the printed indicia, and on newer machines it reads a 2D Mailmark barcode as well. If the print is too faint, smudged or partly missing, that reading can fail. In practice this can lead to items being delayed, returned, or treated as though the postage has not been paid, which can mean a surcharge for your recipient. Keeping impressions sharp is therefore a genuine cost and reliability issue, not simply a cosmetic one.
Print clarity is especially important for Mailmark machines, which print a data-rich barcode that has to be scanned accurately. This is one of the reasons Royal Mail moved Mailmark and Smart machines to blue ink, which its testing found to be more readable for automated sorting than the traditional red.
Common causes of poor franking print
A dried or blocked printhead
This is by far the most common culprit. Franking machines use inkjet printheads, and if the machine sits unused for days or weeks, ink can dry in the tiny nozzles and block them. The result is missing lines, gaps across the impression, or a generally faint mark. Businesses that frank in occasional batches rather than daily are the most affected.
Low, empty or old ink
An obvious cause but an easily missed one. As a cartridge runs low the impression fades before it stops printing altogether, so check your ink level indicator first. Age matters too: ink that has sat idle for several weeks can begin to separate or dry slightly, producing weak impressions even when the cartridge is not empty. Our guide to choosing and storing franking ink explains how to keep cartridges in good condition.
The wrong or a non-approved ink
Royal Mail specifies the ink colour your machine must use. Smart and Mailmark machines must use approved blue ink, while older standard machines use approved red ink. Fitting the wrong colour, or a poor-quality cartridge that does not meet Royal Mail's readability specification, can cause impressions that scan badly even when they look acceptable to the eye. Always fit a cartridge that is approved for your make and model.
A cartridge that is not seated, or dirty contacts
If a fresh cartridge prints poorly straight away, it may not be clicked fully into place, or its electrical contacts and the machine's contacts may be dusty. A cartridge that is misaligned or making a poor connection produces streaky or partial prints. Reseating the cartridge and gently cleaning the contacts often fixes this immediately.
Franking onto an unsuitable surface
Glossy, heavily coloured, padded or very dark envelopes do not absorb franking ink well, so the impression can look patchy however healthy your printhead is. In these cases the machine is working correctly and the envelope is the problem. The simplest fix is to frank onto a self-adhesive franking label and apply that to the item instead.
How to fix faint or streaky franking
1. Run the automatic cleaning cycle
Almost every modern franking machine has a built-in printhead cleaning routine in its menu, often listed under maintenance or ink settings. Run it once, then print a test impression. If there is a slight improvement but the print is still imperfect, run the cycle a second time, as stubborn blockages sometimes clear on the second or third pass.
2. Check the ink level and reseat the cartridge
Use the machine's ink-level display to rule out a simple low-ink situation. Then remove the cartridge, check it is not empty, and refit it firmly until it clicks home. While it is out, carefully wipe the gold or copper contacts with the alcohol wipe supplied with a new cartridge, or a clean lint-free cloth, and do the same to the contacts inside the machine.
3. Clean the printhead by hand
If automatic cleaning has not worked, a gentle manual clean usually does the trick. Remove the cartridge and dab the printhead nozzles with a soft, lint-free cloth or tissue lightly dampened with warm water. Hold the damp cloth against the nozzles for a few seconds to loosen dried ink, then wipe once, gently, and allow the head to dry before refitting. Never use solvents, abrasive materials or excessive force, as the printhead is delicate.
4. Replace the cartridge
If cleaning restores the print only briefly, or not at all, the cartridge itself is likely exhausted or has dried beyond recovery, and a replacement is the reliable fix. Fitting a fresh, approved cartridge and running one cleaning cycle afterward gives the crispest result. Keeping a spare on the shelf means a faded impression never stops your post going out.
5. Switch awkward items to labels
For glossy or dark envelopes, parcels and anything the machine cannot feed cleanly, frank onto a label rather than fighting the surface. Labels give a flat, absorbent, consistent surface and a reliably scannable mark. Our labels guide covers when single and double labels are the better choice.
How to prevent franking print problems
Prevention is far cheaper than lost post. The single most effective habit is to use the machine regularly, even a few items a week, which keeps ink moving through the nozzles and stops them drying. Store spare cartridges flat, in their sealed packaging, somewhere cool and out of direct sunlight, and note the use-by date so you fit the oldest stock first. Always keep to Royal Mail approved ink in the correct colour for your machine, and run an occasional cleaning cycle before a large mailing so you are not troubleshooting under time pressure. If you are unsure which supplies your model takes, the brand pages for FP Mailing and Quadient and Neopost list the right ink and labels for each series.
When to call an engineer
Most print-quality faults are ink or printhead issues you can resolve yourself in a few minutes. If a brand-new, correctly seated, approved cartridge still prints badly after several cleaning cycles, the fault may lie deeper in the print mechanism or the machine's electronics, and it is worth contacting your machine provider or Royal Mail. Royal Mail's own franking machine help pages are a useful reference for compliance questions and for confirming what a valid impression must show.
Frequently Asked Questions
Why is my franking machine printing faint?
A faint impression is usually caused by a partially blocked printhead or a low or ageing ink cartridge. Run the machine's cleaning cycle first, check the ink level, and reseat the cartridge. If the print is still weak after cleaning, the cartridge has most likely dried out or run low and should be replaced with a fresh, approved one.
How do I clean my franking machine printhead?
Start with the built-in automatic cleaning routine in the machine's menu. If that does not fully clear the problem, remove the cartridge and gently wipe the printhead nozzles with a soft, lint-free cloth lightly dampened with warm water, hold it against the nozzles for a few seconds to loosen dried ink, then let the head dry before refitting. Avoid solvents and never scrub, as the printhead is easily damaged.
Can Royal Mail reject a poorly printed franking mark?
Yes. The impression is your proof of payment, and Royal Mail's equipment needs to read it, including the Mailmark barcode on newer machines. If a mark is too faint, smudged or incomplete to be read, the item can be delayed, returned or treated as unpaid. Keeping impressions clear protects the postage you have already paid for.
Does the colour of my franking ink matter?
It does. Smart and Mailmark machines must use Royal Mail approved blue ink, while older standard machines use approved red ink. Using the wrong colour or a non-approved cartridge can cause marks that scan poorly, so always fit ink that is approved for your specific make and model.
How often should I use my franking machine to avoid print problems?
Running even a small amount of mail through the machine each week keeps ink flowing and helps stop the nozzles drying out. If your machine is going to be idle for a longer period, run a cleaning cycle and print a test impression before your next mailing so you can deal with any blockage in advance rather than mid-run.