Print-ready artwork for custom printed envelopes means a high-resolution file (ideally 300dpi), supplied at the right size for the product's defined print area, with text flattened or outlined and no reliance on white ink. In practice that usually means a PNG with a transparent background, or a vector PDF, AI or EPS file, designed to sit comfortably inside the printable zone rather than run to the edges.
Artwork problems are the most common reason a print order stalls, and almost all take minutes to fix. Here is how to prepare files for envelope and mailer printing at Fast Printed Envelopes, including the quirks of pre-made stock that catch designers out.
What "print-ready" actually means
Print-ready means your file can go to press as supplied, with no redrawing or guesswork on our side. We print your artwork rather than design it, so the file you send is the file that appears on your envelopes. Minor adjustments such as resizing are fine, but we do not offer a full design service.
Which file formats work best
Our preference is a PNG with a transparent background at 300dpi. Transparency matters because the envelope itself provides the background: a design saved on a solid white square will print that square as a visible block of ink rather than blending into the material.
We also accept PDF, AI, EPS, PSD and JPG. Vector formats are ideal for logos because they scale without softening; JPG is the weakest, as it cannot hold transparency and compresses detail.
Resolution: why 300dpi is the benchmark
A logo pulled from a website is usually 72dpi and sized for a screen a few centimetres wide, so it turns soft and pixelated once blown up to fit an envelope. Artwork at 300dpi at final print size gives crisp edges on text and fine line work. If you only have a low-resolution file, ask whoever created your branding for the original vector version: resaving a small JPG at a higher dpi does not add detail back.
Colour: CMYK, Pantone and the no white ink rule
We print full-colour CMYK using water-based digital inkjet, so design in CMYK where you can. Bright RGB screen colours, especially vivid blues and greens, shift noticeably when converted for print.
There is no white ink
This is the rule that catches most people out. Our process has no white ink, so anywhere your design is white, the bare envelope material shows through instead. On a white envelope that works perfectly. On kraft, manila or a coloured stock, a "white" logo simply disappears into the background. If your brand mark only exists as a reversed-out white version, supply a dark or full-colour alternative for anything other than white stock.
Pantone matches and metallics
We cannot guarantee exact Pantone matching, particularly on kraft and manila where the warmth of the material influences every colour laid over it, so expect those colours to read slightly muted. Metallic colours such as gold and silver are reproduced as high-quality flat colour equivalents, because foiling, embossing, debossing and spot UV are not part of our inkjet process.
Print areas: why we do not print edge to edge
We print onto pre-manufactured stock envelopes and mailing bags, which is exactly why our turnaround times are so short. The trade-off is that printing happens within a defined print area rather than across the whole product, so full-bleed, edge-to-edge and all-over printing are not available. Which faces are available depends on the product: most items print on the front face, while cardboard envelopes can be printed on the front, the rear, or both sides. Every product page shows the printable area and the available faces for that item, so design to those dimensions and keep a comfortable margin between your artwork, the edges of the envelope and the seal flap. Small shifts in placement are normal when printing onto a made-up product, so avoid designs that only look right if positioned to the millimetre. The full detail sits on our personalisation information and help page.
Choose your envelope size before you finalise artwork, since a DL print area is a very different shape to a C4 one. Our guide to envelope sizes explained covers how C4, C5, C6 and DL compare.
Design for inkjet on stock, not for a glossy brochure
Inkjet printing onto envelope paper behaves differently to litho printing onto coated stock. Large areas of solid, heavy colour are the main thing to avoid, because a lot of ink laid onto an absorbent, uncoated surface can band and print patchily. Designs that work well share a few traits:
- Clean logos, outlined type and line art rather than heavy flood fills
- Contained shapes and marks with plenty of unprinted material around them
- Sensible ink coverage rather than a large solid rectangle of colour
- Good contrast between the design and the envelope colour, especially on kraft
Text, fonts and file housekeeping
Flatten or outline all text before sending your file. If live text arrives in a font we do not have installed, it can reflow or substitute, changing the look of your design. Outlining converts letters into shapes so they print exactly as drawn. Check spelling, phone numbers, web addresses and any return address too, because once a proof is approved that is what gets printed across the whole run.
You also need the rights to everything you send, as uploading artwork confirms you have permission to use the logos, images and typefaces it contains. The UK Intellectual Property Office explains how brand marks are protected.
Leave the address and postage areas clear
Branding should never fight with the post. Keep your design clear of the address panel and of the area where a stamp, franking mark or Postage Paid Impression will sit, and remember that indicia need to stay readable against whatever is behind them. Royal Mail's guide to letter envelope design and clear addressing sets out the clear zones and contrast expectations in detail.
Think about how the envelope closes as well, since the seal area must stay unprinted. Our comparison of gummed, self seal and peel and seal closures explains the differences.
The proof stage is your safety net
Nothing goes to print without your approval. After you order and upload your file you receive a visual proof, and you can amend your design until you are happy with it. Read it properly: check the size and position of your logo, the colours, and every word of any text. Sample orders are the exception, as these run without a proof, and a printed sample remains the best way to judge how colour behaves on kraft or manila.
Quick pre-flight checklist
- Is the file 300dpi at final print size?
- Is the background transparent, or will it print as a block?
- Does anything rely on white ink? If so, is the envelope white?
- Does the design fit the print area with a clear margin to every edge and the seal?
- Is all text outlined or flattened, and proofread?
- Have you avoided large solid blocks of heavy colour?
- Are the address and postage areas left clear?
Frequently asked questions
What file format should I send for printed envelopes?
A PNG with a transparent background at 300dpi is our preferred format. We also accept PDF, AI, EPS, PSD and JPG. Vector files such as PDF, AI and EPS are ideal for logos because they stay sharp at any size, while JPG is the least suitable because it cannot hold transparency.
Can you print white on a brown kraft envelope?
No. Our digital inkjet process does not use white ink, so any white in your artwork appears as the bare material colour and a white logo would effectively vanish on kraft or manila. Supply a dark or full-colour version of your design for anything other than white stock.
Can you print all over the envelope, right to the edges?
No. Because we print onto pre-manufactured stock envelopes and mailers, printing sits within a defined print area and must stay clear of the edges and the seal flap, so full-bleed and all-over printing are not available. Most products print on the front face only, while cardboard envelopes can be printed front, rear or both sides. The exact print area and available faces are shown on each product page.
Do I need to add bleed to my envelope artwork?
No. Bleed is only needed when ink runs off the edge of a sheet, and we do not print to the edge. Design your artwork to sit inside the print area with a clear margin to every edge and to the seal flap.
Will my Pantone brand colour match exactly?
We cannot guarantee an exact Pantone match. We print full-colour CMYK and the material underneath affects the result, so colours on kraft or manila read warmer and more muted than the same file on white stock. A printed sample is the best way to check.
Do you offer a design service if my artwork is not ready?
We can make minor adjustments such as resizing or repositioning, but we do not provide a full design service, so artwork needs to be supplied print-ready. If you are unsure whether your file will work, get in touch before ordering.
Ready to send your artwork?
Preparing artwork properly takes minutes and saves days. If your file ticks the boxes above, browse our custom printed envelopes, choose your size and print area, then upload your artwork. Not sure about your file? Our team will happily look it over first.