The standard tri-fold brochure size is 8.5 × 11 inches (US Letter  279.4 × 215.9 mm) laid flat in landscape and folded twice. Each panel is about 3.67 inches wide and the folded brochure measures about 3.69 × 8.5 inches. At 300 DPI the flat sheet is 3300 × 2550 pixels.

Those are the quick numbers. A print-ready file needs a little more: exact panel widths fold lines bleed and a safe area. This guide gives all of them in inches, millimetres and pixels for Letter and A4 paper.

Tri-fold brochure size at a glance

In centimetres a Letter tri-fold is 27.94 × 21.59 cm and an A4 tri-fold is 29.7 × 21 cm. Letter is the default in Canada because most Canadian offices and printers work with 8.5 × 11 in paper. A4 appears in many online templates so check which size a template uses before you download it. Tabloid (11 × 17 in) also works for a larger tri-fold with wider panels.

Why the panels are not equal thirds

A tri-fold has two folds and six panels three on each side. Dividing the sheet by three gives 3.67 in on Letter which is fine for a rough mock-up. A print file should not use equal thirds because the panel that tucks inside must be slightly narrower than the other two. If all three were the same width the inner panel would push against the fold and the brochure would bulge instead of closing flat.

The usual allowance is 1/16 in (1.6 mm) on Letter and Legal and 3 mm on A4. Check your printer’s template since allowances vary.

Panel widths and fold lines

Build the artwork as two landscape spreads one for the outside and one for the inside rather than six separate pages. Measure the fold guides from the left edge of each spread.

Every row adds up to the full sheet width: 3.625 + 3.6875 + 3.6875 = 11 in and 97 + 100 + 100 = 297 mm. If your panel widths don’t add up the file is wrong before it reaches the printer. The two sides mirror each other which is why the narrow panel sits on the left of the outside spread and on the right of the inside spread.

At 300 DPI a Letter panel is about 1106 px wide (1088 px for the narrow one) and 2550 px tall.

Bleed and safe area

Bleed is background colour or imagery that extends past the trim edge  so no white slivers show if the cut shifts. A common bleed is 0.125 in (3 mm) on every edge which makes the Letter file 11.25 × 8.75 in or 3375 × 2625 px. On A4 it becomes 303 × 216 mm.

The safe area is the margin inside the trim where text and logos must stay. Keep important content at least 0.125 in (3 mm) from every trim edge and further around 0.2 in (5 mm), from fold lines  where the crease can distort it. Printers set these values differently so always use your printer’s own template.

OreoPrint file setup: insert OreoPrint’s confirmed bleed and safe-area values and link the  tri-fold template here.

Which tri-fold size should you choose?

• Letter (8.5 × 11 in): the standard. It fits brochure racks, envelopes and mailers and it is the cheapest to print.
• Legal (8.5 × 14 in): about three inches longer so each panel has more room. Choose it only when a section really needs the space.
• Tabloid (11 × 17 in): for large poster-style panels.
• A4 (210 × 297 mm): the standard outside North America. Use it for customers abroad.

Brochures are commonly printed on 80 to 100 lb stock. Ask your printer which paper they recommend for your design.

Bi-fold brochure size

People who search for tri-fold sizes often want the bi-fold size too. A bi-fold is the same Letter sheet folded once  which gives two panels per side. Each panel is 5.5 × 8.5 in or 1650 × 2550 px at 300 DPI. A bi-fold has more room per panel but fewer panels so choose it for simple messages.

Avoid common sizing mistakes

• Use two spreads, not six pages, so the panels line up across the folds.
• Keep text off the folds. Don’t let a sentence or a thin line run along a crease.
• Put your call to action where the reader finishes: the last inside panel and the back panel.
• Print one copy at 100% scale and fold it before you send the file.

Tri-fold brochure size FAQs

What is the standard size of a tri-fold brochure?

The standard size is 8.5 × 11 inches (US Letter) laid flat in landscape and folded twice. Each panel is about 3.67 inches wide and the folded brochure is about 3.69 × 8.5 inches.

What is the tri-fold brochure size in pixels?

At 300 DPI a Letter tri-fold is 3300 × 2550 pixels flat and an A4 tri-fold is 3508 × 2480 pixels with a 0.125 in bleed the Letter file is 3375 × 2625 pixels. For screen-only use at 150 DPI halve those numbers.

Is a tri-fold brochure Letter or A4?

In Canada and the United States  it is Letter (8.5 × 11 in). A4 (210 × 297 mm) is the standard in most other countries. Choose the paper size that matches where you will print and distribute the brochure.

How many folds does a tri-fold brochure have?

Two. The two folds create three panels on each side of the sheet, six panels in total. The name refers to the three sections not the number of folds.

Why is one panel of a tri-fold narrower?

The panel that tucks inside has to fit within the other two. Making it about 1/16 in (1.6 mm) narrower on Letter or 3 mm on A4 lets the brochure close flat without the edges splaying.

Get your file right the first time

Start from the correct template, keep text inside the safe area and print a folded proof. When your design is ready order custom tri-fold brochures from OreoPrint or download the free tri-fold template.