Offset printing transfers ink from a printing plate to a rubber blanket, and from the blanket to the sheet, which is where the name comes from. A plate is made for each colour before anything prints, so the setup is significant, and the cost per sheet then falls sharply as the run gets longer. This guide follows an offset job from the file to the finished sheet.
What does “offset” mean in offset printing?
Offset describes the route the ink takes. The image is not printed straight from the plate onto the paper: the plate inks a rubber blanket, and the blanket lays the image onto the sheet. Each colour has its own plate, made for the run, and every plate prints the same image on every sheet until the run ends.
That last point explains most of what offset does well and the one thing it cannot do. Because the image is fixed in the plate, offset holds colour more consistently across a very long run. For the same reason, offset cannot put a different name, number or code on each sheet. Variable data is a digital press job, and numbering on a printed sheet is a distinct pass.
The whole process, in order:
| Step | What happens | What it means for your job |
|---|---|---|
| File check and proof | The artwork is checked and a proof is approved | Wording and colour are settled before any plate exists |
| Plate making | One plate per colour, made for the run | A correction after this point means a new plate |
| Make-ready | Plates are fitted, and colour and register are brought to the approved proof | The setup is paid here, once per run |
| The run | The plate inks the blanket, and the blanket prints the sheet | The cost per sheet falls as the run gets longer |
| Ink setting | Printed sheets rest before lamination or folding | An interval that is planned into the turnaround |
| Finishing | Lamination, creasing, folding, binding, cutting | The same finishing steps as any printed job |
What happens to the artwork before an offset job goes to press?
Before any plate is made, the file is checked and a proof is approved, because everything after this stage is built from that file. The file standard is the same as for digital printing: PDF/X-4 with 3 mm bleed, images at 300 dpi at final size, CMYK colour, and any Pantone spot colour that must be matched named exactly in the file.
The proof carries more weight on offset than on a short digital run, because a correction made after the plates exist means making plates again. Where colour is critical, a digital proof on the actual stock can be checked before a long offset run. It answers the colour question before the plates are made, which is a far smaller step than reprinting a long run to correct a colour.
Two things in the file deserve a second look on an offset job. The first is spot colour: a brand colour that has to match exactly should be named as its Pantone reference, not left as a CMYK mix, because offset can run the actual ink. The second is anything that changes from sheet to sheet. If the design needs a different name or number on every piece, that is decided before the process is chosen, not after. The artwork guide covers the rest of the file set-up.
How are offset printing plates made, and why does each colour need one?
An offset plate carries one colour of the image. A full-colour job built in CMYK is separated into its four process colours, and a plate is made for each, so the press can lay down cyan, magenta, yellow and black in turn. A Pantone spot colour is run as the actual ink on a plate of its own, which is how offset holds a spot colour exactly.
This is the practical difference behind a common question. A digital press simulates a Pantone in process inks; an offset press can be given a plate and the actual ink for one specific colour. If an exact brand colour is the point of the job, name the Pantone reference in the file and say so in the enquiry.
Plates are made for the run rather than kept, so a repeat of the same job starts with plate making again. That is one reason the setup is significant on every offset run, including a reorder, and one reason short runs rarely suit offset.
What is make-ready on an offset press?
Make-ready is the setup between fitting the plates and printing the first sheet that matches the approved proof. The plates are mounted, the ink is brought up evenly across the sheet, and the colours are brought into register so that each one lands exactly on top of the others. Only then does the counted run begin.
Make-ready is the reason offset carries significant setup and digital carries almost none. The setup is paid once per run, whatever the quantity, so it dominates a short run and matters less and less as the run grows. Choosing offset for a run of two hundred is the classic mismatch: the plate setup dominates the job and there is nothing to gain from it.
It is also the reason a digital press reaches a first sheet immediately, while an offset press reaches one only after plates and make-ready. For a long run that interval is part of the plan rather than a delay.
What happens during an offset print run?
Once make-ready is signed off, the run itself is repetitive by design. On each impression the plate is inked, the plate transfers its image to the rubber blanket, and the blanket prints it onto the sheet. A full-colour sheet receives each colour in turn. The plate never touches the paper, which is the “offset” in the name.
How the sheet takes the ink depends on the stock:
- Coated paper such as gloss art paper: offset ink lies flatter into the coating, where digital toner sits on it with a very slight sheen. Side by side the difference is visible; at arm’s length it is not.
- Uncoated woodfree: the trade also calls it offset paper, because uncoated stock absorbs ink, which is exactly what offset ink is formulated for. Chroma drops on both processes, slightly more on offset because the ink sinks into the fibre, so artwork for uncoated stock should be built for it.
- Large flat solids: where a huge flat area of one colour is the design, offset is the more even result.
- Heavier and unusual stocks: digital handles the held range to about 400 gsm; offset covers heavier and unusual stocks more easily.
Why do offset sheets need time before finishing?
Offset ink has to set before a film can be bonded over it or the sheet folded through it. That interval is a property of the ink rather than a scheduling choice, so it is planned into the turnaround rather than worked around. Digital sheets can go to finishing as soon as they are printed; offset sheets need the ink to set first.
In practice, finishing follows the ink, not the press. A laminated and folded piece runs in a fixed order: print, let the ink set, laminate, then crease and fold, because the film has to bond before a sheet can be creased without cracking. Anything over 170 gsm is creased before it is folded.
Standard turnaround is 7–14 working days on either process, and offset carries plate making and the ink setting interval inside that window rather than on top of it. Express is quoted per job, against the specification.
When does offset printing suit a job?
Offset suits long runs of the same image, exact spot colours and large flat solids. For typical sheet-fed work the crossover with digital sits roughly between one and two thousand sheets, and it moves with the stock, the size and the number of colours. Below it, digital is almost always the answer; above it, offset usually is.
The side-by-side comparison of the two processes is in offset vs digital printing, and the digital printing page sets out where the crossover sits. For an offset buyer, the signals are short:
- A long run of one design: the setup is paid once, and the cost per sheet then falls sharply.
- A Pantone colour that must match exactly: offset runs the actual ink.
- A large flat solid as the design: offset gives the more even result.
- Not offset: a different name or number on every sheet, or a run of a few hundred.
You do not have to choose the process yourself. Send the quantity with the specification, and the quotation states which process the job assumes and what that means for colour, stock and cost.
Worked example: following a brochure through an offset run
Following one job through each stage shows where the offset decisions fall. In this example, a long run of a double-sided A4 tri-fold brochure with one Pantone brand colour goes from file check to folded, packed brochures, and each stage below maps to a step described above, from the proof before the plates to the interval before folding.
Hypothetical planning example. Actual production timing, paper availability, and logistics are confirmed individually upon artwork and specification review.
A marketing team needs 5,000 A4 tri-fold brochures for a product launch, with the logo in one Pantone brand colour on the front.
- Specification: 5,000 brochures on 157 gsm gloss art paper, A4 flat, drawn at 216 × 303 mm including 3 mm bleed, printed in CMYK on both sides plus one named Pantone on the front, folded as a tri-fold.
- Process: the quantity sits well above the crossover and the brand colour has to match exactly, so the quotation assumes offset.
- File check and proof: the PDF/X-4 file is checked, the Pantone is confirmed as named exactly in the file, and a digital proof on the actual stock is checked for the brand colour before any plate is made.
- Plates: a plate is made for each process colour and one for the Pantone ink.
- Make-ready: the plates are mounted, and colour and register are brought to the approved proof before the counted run starts.
- The run: each sheet takes the image from plate to blanket to paper, colour by colour.
- Ink setting and finishing: the printed sheets rest until the ink has set, then they are folded, packed and delivered. Standard turnaround is 7–14 working days, with plate making and the ink setting interval inside it.
Frequently asked questions
What is offset printing?
Offset printing is a process in which ink is transferred from a printing plate to a rubber blanket and from the blanket to the sheet. A plate is made for each colour before the run, so the setup is significant, and the cost per sheet then falls sharply as the quantity rises. It suits long runs of the same design.
Why is it called offset printing?
Because the image is offset rather than printed directly. The plate never touches the paper: it inks a rubber blanket, and the blanket lays the image onto the sheet. Each colour has its own plate, and every plate prints the same image on every sheet of the run.
Can offset printing match a Pantone colour?
Yes. Offset can run the actual Pantone ink on a plate of its own, which is how a spot colour is held exactly. A digital press simulates a Pantone in process inks instead. Name the Pantone reference exactly in the file and mention it in the enquiry.
Why can offset prints not be laminated or folded straight away?
Offset ink has to set before a film can be bonded over it or the sheet folded through it. That interval is a property of the ink rather than a scheduling choice, so it is planned into the standard turnaround rather than added on top of it.
Can offset printing do variable data or numbering?
Not on the plate. An offset plate prints the same image every time, so a different name, number or code on every sheet is a digital press job. Numbering on a printed sheet is handled as a distinct pass over the sheet.
How does EZ Print quote an offset printing job?
EZ Print produces both digitally printed and offset printed work in Singapore, and has done since 2017. Send the stock, quantity, sides, finish, size and deadline, and the quotation states which process the job assumes and what that means for colour, stock and cost. Standard turnaround is 7–14 working days on either process, and express is quoted per job.
Above roughly two thousand, offset usually becomes the sensible route for long runs of flyers, brochures and booklets. Send your specification through the quote request page and the process comes back with it.
Same-day and urgent printing available. Subject to artwork approval, payment, print type and production availability. Timing confirmed per job.