Merge PDF files

What people merge, and how to set it up

• A scanned form and its attachments. Many offices want one file: the signed application followed by proof of address, pay stubs or ID. Put the form first and the attachments after it, in the order the checklist asks for, so the person reviewing it doesn’t have to hunt.
• Chapters into a book or report. Long documents are often written as separate files per chapter. Merge them in chapter order, then give the whole thing continuous page numbers with add page numbers, since each chapter’s own numbering restarts at 1.
• A year of invoices or statements. An accountant or a tax preparer usually prefers one PDF to twelve. Merging monthly statements into one file also makes them easy to search for a payee or an amount.
• Job, school and visa applications. Upload portals often accept a single PDF per section. Merge the cover letter, résumé and references, or the transcript pages, into the one file the portal expects, and check its size limit before you upload.

Getting the order right with file names

Sort by name puts files in the order their names would appear in a well-organized folder, reading numbers as numbers. That makes a little renaming before you start the fastest way to order a long set:

File names	Sorted order	Tip
Chapter 10, Chapter 2, Chapter 1	1, 2, 10	Numbers sort as numbers, no leading zeros needed
2026-03 Statement, 2026-01 Statement	January, then March	Write dates year first, then month
March Statement, January Statement	January, March	Alphabetical only: April would come first, so use numbers for months

You can still move any file up or down afterwards, for example to put a cover page first.

Merging on a phone

The tool works the same in Safari, Chrome and other mobile browsers. Files you received by email need to be saved to your phone first (in most mail apps: tap the attachment, then the share button, then Save to Files or Download). On a small screen, use the arrow buttons rather than dragging to reorder. Very large scans, hundreds of megabytes in total, can be too much for a phone’s memory; merge them in smaller batches, or on a computer.

Protected files

PDFs from banks, government sites and some employers are often locked. A locked file shows a warning in the list and is skipped rather than breaking the merge. To include it, open it in your PDF reader, then save a copy without the password, or print it and choose "Save as PDF" or "Microsoft Print to PDF" as the printer. A printed copy keeps the look of the pages, but links and fillable fields may not survive.

Merge or combine?

They are the same thing. People in the US tend to say "combine PDF", and in India and many other countries "merge PDF" is the usual phrase. Whichever you call it, the pages are copied into the new file exactly as they are, so text stays selectable and nothing is uploaded. For the opposite job, split a PDF into parts or extract the pages you need; to tidy the merged file, reorder or delete pages or rotate sideways scans.