The document is finished; the letterhead isn't on it. Overlay, under, done
Add letterhead to an existing PDF: overlay it UNDER the content in your browser — physics guarantees your text stays visible — or stamp OVER for a banner.
UnboundPDF is a free suite of 53 PDF and image tools that run entirely in your browser — merge, split, compress, edit text, OCR in 126 languages, redact, sign, convert and archive to PDF/A. Your document is read and written by the page on your own device; there is no document-upload endpoint in the core tools, no account, no watermark and no daily cap. Every result can be checked — with the Network tab, or with the Document Passport the Workspace writes for a chain of steps.
Quick start. Open Overlay PDF: your document in the first slot, the letterhead PDF in the second, mode UNDER, pages all (or first-page-only for letter convention), download. Company paper, retroactively.
The situation
The report came out of the accounting tool, the letter out of a colleague's template, the contract from the counterparty — correct, finished, and naked of your identity. Rebuilding them inside your letterhead template is an hour; laying the letterhead under them is a minute.
Under versus over, without folklore
UNDER paints your document last — so the letterhead physically cannot hide your text, however opaque its background. OVER paints the overlay last — the right mode for a COPY or SPECIMEN banner that should sit on top. The honest edge case runs the other way: a document of full-page scans is itself opaque and will hide an UNDER letterhead; the page explains it, and first-page-only mode usually resolves it (scans rarely start a letter).
Covering is not removing
A banner that hides text does not delete it — select-all still finds every word, exactly like the crop trap. Overlays are for identity and status; content that must be gone goes through Redact PDF.
Troubleshooting
My letterhead is a Word file. Convert it once, keep the PDF as your standing letterhead. The letterhead blocks a scan. That page is opaque raster — use first-page-only, or accept OVER with a small header-strip letterhead. I need it on every future document. Overlay each as it comes; the letterhead PDF is reusable forever.
Frequently asked questions
Overlay or headers — which do I want?
A full-page design (your letterhead as designed) is the overlay. A one-line footer with a logo is Headers & Footers. A diagonal DRAFT is Watermark.
Will the letterhead cover my text?
Not in UNDER mode — the document paints last, so an opaque letterhead covers only the page background. OVER is the covering mode, for stamps.
Does a stamp that covers text remove it?
No — covering is not removing; the text underneath is still extractable, and the page says so with a pointer to Redact PDF.
Try it yourself
Free, private, no account. Runs entirely in your browser.
