Print pre-flight checklist: 12 checks before you send a file.

The 12-point pre-flight checklist

This is written for printers, sign makers and the people who send them files. It assumes you did not design the thing and have no intention of learning. Export settings drop bleed, fonts and image data without telling you, so check the PDF you are about to send, not the file you built.

1. check_circle 3 mm bleed, all round. Every background, photo and colour block must run 3 mm past the trim on all four cut edges. Without it the guillotine lands on bare paper and the finished piece shows a thin white sliver down one side. Large format is a different job, so ask your printer what bleed they want on that.
2. check_circle 300 ppi at final size. Images need 300 ppi at the size they are placed, not the size they came out of the camera. A 300 ppi image scaled to 200% in the layout reaches press at 150 ppi and prints soft, with visible pixels on any close-viewed leaflet or card. Posters and banners viewed from a distance can go lower: ask your printer, typical is 150 ppi.
3. check_circle CMYK, never RGB. Convert every image and every colour swatch to CMYK before export, using the profile your printer names. RGB greens and oranges sit outside the CMYK gamut and come back dull or shifted on press, and nobody sees it until the sheets are running.
4. check_circle Total ink under 300%. Keep the combined C, M, Y and K in dark areas at or under 300%, or whatever limit your printer gives you, and set small text and fine lines in 100% K only. Builds over the limit will not dry, they set off onto the sheet below and block in the stack, and four-colour black on 8 pt type fringes at the edges when the plates misregister.
5. check_circle Fonts embedded or outlined. Every font must be embedded in the PDF or converted to outlines. A missing font gets substituted by the RIP, so your headline reflows, drops a line or changes width, and the first person to notice is the customer holding the box.
6. check_circle No missing images. Check that every placed image is embedded or linked and actually present, with no grey placeholder frames and no 72 ppi pictures lifted off a website. A broken link exports as a blank box or a soft preview and the job goes on press with a hole in it.
7. check_circle Page size and crop marks. Set the document page to the finished size plus 3 mm on each edge, so a 210 x 297 mm A4 job is built at 216 x 303 mm, and put crop marks 3 mm outside the trim. A page built at trim size leaves the bleed nowhere to live, so the printer either rejects the file or scales it to fit and throws your margins out.
8. check_circle 5 mm safe area. Keep all text, logos, page numbers and QR codes at least 5 mm inside the trim. Normal cut variation is a millimetre or two either way, and a phone number with its last digit shaved off is a reprint, not a trim.
9. check_circle PDF/X-1a, flattened. Export as PDF/X-1a, which flattens transparency, embeds fonts and locks colour to CMYK, or PDF/X-4 if your printer asks for it. A plain PDF, a JPEG or a screenshot carries RGB, live transparency and unembedded fonts, and the RIP resolves all three differently from what you saw on screen.
10. check_circle Spot colours and overprint. Check the spot colour list and the overprint preview before you send. A stray Pantone left in a CMYK job adds a fifth plate the printer is not running, and an accidental overprint makes white text disappear into whatever sits behind it.
11. check_circle Named file, one version. Name the file with the job and a version number, for example menu-a5-v4.pdf, and send one final file with one named approver. Two attachments called final and final2 in the same inbox is how the wrong version ends up on press.
12. check_circle Proof it at 100%. Open the exported PDF, not the design file, and read every page at actual size, including phone numbers, prices, dates, QR links and the legal line. Approve that proof before plates are made, because every fault above costs minutes to fix now and a full reprint once the ink is down.