How to Merge PDF Files on iPhone (Combine PDFs into One)
Updated
Quick answer
Open PDF Slayer, tap Merge, add the PDFs you want to combine, drag them into the right order, and tap Merge. The combined PDF is created on your iPhone and saved wherever you choose — no computer or online tool required.
Three separate scans, a cover letter, and an ID photo — and the recipient wants "one PDF, please." Merging PDFs is one of the most common document tasks, and you can do it entirely on your iPhone.
Online PDF mergers work, but they require uploading every file — a bad trade for paperwork like applications, tax documents, or contracts. Merging on-device is faster and keeps everything private.
Merge PDFs with PDF Slayer
Open the Merge tool
Launch PDF Slayer and choose Merge PDFs.
Add your files
Pick the PDFs from the Files app — you can add as many as you need.
Drag to reorder
Arrange the files in the exact order they should appear in the final document.
Merge and save
Tap Merge. The combined PDF is generated on your device — save it to Files or share it directly.
Free on the App Store. Works 100% offline — your documents never leave your iPhone.
Get PDF Slayer FreeCan the iPhone merge PDFs without an app?
Partially. In the Files app you can select multiple PDFs, long-press, and choose Create PDF. It works for a quick join, but you get no control over page order beyond file naming, no preview, and no way to fine-tune the result.
PDF Slayer shows your files before merging and lets you drag them into the exact order you want. Afterwards you can keep working on the merged file — reorder or delete individual pages, sign it, or password-protect it — without switching apps.
Merging scans, images, and PDFs together
If some of your source material is photos rather than PDFs, convert the images to PDF first (PDF Slayer does this in one step), then merge. You can also scan paper directly to PDF with the camera and combine the scan with existing files.
Frequently asked questions
Does merging reduce PDF quality?
No. Merging combines the original pages as-is — nothing is recompressed or downscaled.
Can I reorder pages after merging?
Yes. Open the merged file in the Organize tool to drag pages into a new order, rotate them, or delete extras.
Is there a limit on how many PDFs I can combine?
No practical limit — merge as many files as your workflow needs, all processed locally on your iPhone.
Are my files uploaded when I merge them?
No. PDF Slayer merges entirely on your device. It works even in airplane mode.