On this page 8 sections
The standard poster sizes in the UK follow the A-series: A5 (148 x 210 mm), A4 (210 x 297 mm), A3 (297 x 420 mm), A2 (420 x 594 mm), A1 (594 x 841 mm) and A0 (841 x 1189 mm). Two inch formats, 20 x 30 in and 30 x 40 in, are also common for wall posters and film-style prints.
Picking a size is mostly about distance. A poster that someone reads at arm’s length on a noticeboard can be small; one that has to catch the eye across a car park, a school hall or a shop floor needs to be big. The table below gives the exact measurements and the jobs each size tends to do well.
UK poster size chart
| Size | Millimetres | Inches (approx.) | Typical use |
|---|---|---|---|
| A5 | 148 x 210 | 5.8 x 8.3 | Counter cards, shelf notices, lift and lobby notices |
| A4 | 210 x 297 | 8.3 x 11.7 | Noticeboards, window cards, small frames |
| A3 | 297 x 420 | 11.7 x 16.5 | Shop windows, event notices, menus on the wall |
| A2 | 420 x 594 | 16.5 x 23.4 | Gig and event posters, A-board inserts, bedroom walls |
| 20 x 30 in | 508 x 762 | 20 x 30 | Living room prints, film-style posters |
| A1 | 594 x 841 | 23.4 x 33.1 | Retail displays, conference posters, A-boards |
| 30 x 40 in | 762 x 1016 | 30 x 40 | Statement wall pieces, foyer displays |
| A0 | 841 x 1189 | 33.1 x 46.8 | Academic posters, exhibition walls, large window displays |
How the A sizes relate to each other
Each A size is exactly half of the one above it. Fold an A0 sheet in half across its long side and you get A1; fold A1 and you get A2, and so on down to A5. Every size keeps the same proportions, roughly 1 to 1.41, so a design made for A3 can be scaled up to A1 or down to A4 without being stretched or cropped. That makes the A-series the safest choice if one design has to work at several sizes, for example a small version for a counter and a large one for the window.
The inch formats do not share that ratio. A 20 x 30 in poster is a 2 to 3 shape, closer to a camera photo, and 30 x 40 in is 3 to 4. If you move artwork between an A size and an inch size, expect to adjust the layout or accept a crop at the edges.
Choosing a poster size by viewing distance
A quick way to choose: think about where the reader will stand, then check the size of your smallest important text.
- Up to about 1 metre away (noticeboards, toilets, lift lobbies): A4 or A3 is plenty.
- A few metres away (shop windows, corridors, A-boards on a pavement): A2 or A1.
- Across a room or street (exhibition walls, large windows, foyers): A1, 30 x 40 in or A0.
- Roadside or hoarding sites: billboard formats, which are a different family altogether.
Headline text needs to grow with the poster. On an A3 notice, a headline around 60 to 90 pt reads well from a short distance; on an A1 poster seen across a shop floor, it often needs to be two or three times that. If you are unsure, print a section of the design on your home printer at actual size, tape it up and walk back to where your audience will be.
Portrait or landscape
Every size in the chart can be printed either way round. Portrait suits most posters because it matches doors, pillars, windows and noticeboards. Landscape works better for timelines, panoramic photos, team photos and anything going above a counter or along a corridor. Set the orientation in your artwork before you export it; the poster is printed as the file is laid out.
Which materials come in which sizes
Size and material go together. Our standard poster printing covers A5 through to A0 and both inch formats, on 150gsm satin poster paper, 120gsm blueback, 440gsm PVC or 400gsm PVC Free. If you already know the size you need, the dedicated pages are quicker: A3 posters, A2 posters, A1 posters and A0 posters all list every material and quantity break, from a single copy up to 99.
For larger runs of smaller posters, such as 250 A4 notices for a campaign, the indoor poster range uses lighter papers in gloss, silk, smooth and uncoated finishes and starts at 25 copies.
Sizes for frames
A-series frames are easy to find in the UK, so A4, A3, A2 and A1 posters slip straight in. Many frames sold as 50 x 70 cm or 40 x 50 cm are designed for photographic sizes instead; an A2 poster in a 50 x 70 frame needs a mount to fill the gap. Measure the frame’s opening, not the outside edge, before you order.
Setting up artwork at the right size
- Create the document at the finished size you are ordering, for example 594 x 841 mm for A1.
- Add 3 mm bleed on each edge, so the canvas becomes 600 x 847 mm for A1, and extend background colours and images into it.
- Keep text and logos at least 5 mm inside the trim line.
- Use images that hold at least 150 dpi at the full printed size; more is better for small posters read up close.
- Export a PDF with fonts embedded.
Every file is checked automatically before it is printed, so if something is the wrong size or too low in resolution, it is picked up before your poster is made.
Questions
What is the most common poster size in the UK?
A2 and A3 are the sizes most people reach for. A3 suits windows and noticeboards, while A2 is the classic size for event and gig posters. For displays seen from further away, A1 is the usual step up.
How big is an A1 poster in cm?
An A1 poster measures 59.4 x 84.1 cm, which is 594 x 841 mm or roughly 23.4 x 33.1 inches.
Is 30 x 40 inches bigger than A0?
No. A 30 x 40 inch poster is 762 x 1016 mm, so it is slightly smaller than A0 (841 x 1189 mm) in both directions, but larger than A1.
Can I scale one design to several poster sizes?
Yes, if you stay within the A-series. A5 to A0 all share the same proportions, so artwork scales up or down cleanly. Moving to an inch size such as 20 x 30 in needs a small layout change.
What size poster should I use for an A-board?
Most pavement A-boards in the UK take A1 or A2 inserts. Measure the visible window of your board and choose the matching size.