A binding margin is extra space added to the spine side of a printed document to keep text and images from getting trimmed during binding. Most designers set it to 0.5 inches and enable mirror margins.
What’s happening here?
Your content is getting trimmed into the spine because the binding margin is too small for your chosen binding method.
In two-sided layouts, the left margin of page 2 becomes the right margin of page 1. Word calls this “mirror margins.” The gutter is that extra strip along the spine edge that accounts for trimming during binding. Without it, your content can vanish into the binding glue or fold. According to Microsoft Support, mirror margins keep spacing consistent across odd and even pages.
How do I fix this?
Turn on mirror margins in Microsoft Word and set the gutter to 0.5 inches to give your binding enough room.
These steps work in Microsoft 365 (Version 2405 as of June 2026) and Word 2021/2024. Open your document, then head to Layout → Margins → Custom Margins. In the Page Setup dialog, set Gutter = 0.5 in. (or 1.27 cm), pick Multiple pages → Mirror margins, and confirm the “Inside” margin shows 0.5 in. (gutter) plus your base margin (usually 1 in.). Click OK and watch your text reflow away from the spine.
That didn’t work. Now what?
Bump up the gutter size based on your printer’s specs or binding type so nothing gets trimmed.
- Printer-specific gutter – Digital presses like the HP Indigo 2025 might add a 0.3125-inch gutter automatically. If the printer needs 0.75 inches, adjust your gutter in Word before exporting.
- Saddle-stitch booklets – For booklets under 64 pages, printers often fold the spine outward. Keep the gutter at 0.5 inches; the fold itself creates extra space.
- PDF export glitch – In Word, go to File → Export → Create PDF/XPS → Options → check “Include gutter margin” so Acrobat doesn’t crop the inside edge.
How can I avoid this in the future?
Use a prebuilt template, enable guides, and request printer proofs to keep your binding margins consistent.
| Task |
Action |
Timeline |
| Template |
Save a Word template (.dotx) with gutter = 0.5 in. and mirror margins already set. Apply it to every new document. |
Once, then reuse |
| Style check |
Turn on View → Ruler → Show guides. A faint dotted line 0.5 in. from the spine will warn you if text creeps too close. |
Before final export |
| Printer proof |
Ask for a digital proof with crop marks. Measure the spine edge; if less than 0.4375 in. is visible, increase gutter to 0.625 in. |
At least 2 days before deadline |
| Binding type |
Switching from perfect bind to lay-flat? Bump gutter to 0.75 in.—the spine doesn’t compress like it does with perfect binding. |
Change request stage |
Run this quick test: Print a single sheet, fold it in half, and hold it up to a light. If any text or images sit within 0.25 in. of the fold, adjust the gutter and test again. According to Adobe Acrobat Printing Guide, crop marks and gutters work together to make sure trimming is accurate.
