Quick answer: US Letter paper measures 8.5 × 11 inches, equivalent to 215.9 × 279.4 mm. It is an inch-based North American format rather than an ISO A-series size.
Measurement note: dimensions are stated width × height in portrait orientation. Turn the sheet through 90 degrees for landscape use. Millimetres are the controlling values for ISO sizes; inch figures are rounded conversions.
US Letter dimensions
| Unit | Width | Height |
|---|---|---|
| Inches | 8.5 in | 11 in |
| Millimetres | 215.9 mm | 279.4 mm |
| Centimetres | 21.59 cm | 27.94 cm |
Common uses for US Letter
- Office letters and reports
- Forms and school work
- Home and business printing
Printer and software setup
Select US Letter in both the document and printer driver. If it is not listed, create a custom page of 8.5 × 11 inches. Confirm orientation, scaling and tray selection. A “fit to page” option can alter dimensions and type size, which is unacceptable for forms, labels, technical drawings or any item requiring scale accuracy.
Comparison with ISO sizes
US Letter does not share the 1:√2 aspect ratio of A-series paper. Converting a layout to A4 or another ISO size may therefore change margins, line breaks and page count. Use the UK and US comparison guide when preparing documents for both markets.
Bleed and commercial printing
For a full-bleed finished piece, keep the trim at 8.5 × 11 inches and extend backgrounds beyond the edge by the printer’s specified amount. A common North American allowance is 0.125 inch on each edge, but supplier templates take priority.
Frequently asked questions
What is US Letter in millimetres?
US Letter is 215.9 × 279.4 mm.
Can US Letter be printed on A4?
It can be scaled or positioned on A4, but the proportions differ. Printing at 100% may crop one dimension or leave unequal margins depending on the direction of conversion.
Is US Letter an ANSI size?
Some common office formats correspond to named ANSI sizes, while others are customary formats. The ANSI guide explains the A–E engineering sequence.
Common mistakes to avoid
- Entering rounded inch conversions when exact millimetres are available.
- Confusing finished trim with bleed or parent-sheet dimensions.
- Allowing the printer driver to scale automatically.
- Assuming a named size is identical in every national standard.
- Ordering paper before checking the printer’s minimum, maximum and supported weight.
- Judging readability only on a zoomed computer display.
For US Letter Paper Size, the most dependable approach is to retain the standard’s controlling unit, state the dimensions in the purchase order, use a supplier template and approve a full-size proof. This is especially important when the project moves between countries, software packages or production methods.
How to specify the size without ambiguity
For US Letter Paper Size, a reliable print specification states more than the familiar format name. Give the finished width and height, measurement unit, orientation, number of pages or panels, paper weight, surface, colour process, bleed, finishing and quantity. This prevents regional names and printer defaults from silently changing this particular job.
- Finished size: write width × height and identify portrait or landscape.
- Artwork size: distinguish the trimmed page from any larger bleed canvas or parent sheet.
- Stock: specify grammage or basis weight, coating, colour and recycled or certified requirements.
- Finishing: state folds, scoring, binding, drilling, corner rounding, lamination or mounting.
- Tolerance: ask the supplier what cutting, folding and registration variation should be expected.
When ordering US Letter Paper Size, a short name alone leaves important decisions unstated. A specification such as “finished size as stated above; portrait; 3 mm bleed; 170 gsm uncoated white stock; full colour both sides; scored where shown” is harder to misinterpret. When the format has regional variants, include the governing standard or exact dimensions every time.
Make a full-size physical proof
Screens do not communicate the physical scale of US Letter Paper Size reliably. Before a large order, print a representative page at 100%, trim it to the stated size and use it as the finished item will be used. Measure one horizontal and one vertical feature with a ruler. Fold it, place it in its envelope or holder where relevant, view it from the intended distance and ask someone unfamiliar with the design to find the main information.
A proof of US Letter Paper Size should check more than spelling. Look for text that is technically present but difficult to read, lines that sit too close to the trim, images whose important details enter a fold or binding area, barcodes or QR codes that do not scan, and stocks that crack or show through. For colour-critical work, a calibrated contract proof or press proof is more informative than an office print.
Sources and standards
The measurements and production guidance in this guide were checked against the following standards bodies, postal operators and print-platform specifications. Standards can be revised or withdrawn, so check the linked record when a contractual or regulated specification matters.