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Merge PDF for tax return

Combine several PDF files into one document, in the order you want.

Drag the files to change their order

Options

Drag the files to change their order

Processing your file…

✅ Your file is ready!

Continue with your PDF

Requirements for a tax return

  • Safe size target: 5 MB
  • Usual paper format: A4
  • Contains personal data: add a password before emailing it.
  • Limits differ between organizations: always check the maximum size shown on the upload form.

How to use Merge PDF

  1. 1

    Drag and drop your PDF files into the upload area, or click “Select files”.

  2. 2

    Check the options — they are already pre-set for this page.

  3. 3

    Click “Merge PDF”. Your file is processed in RAM in a few milliseconds.

  4. 4

    Download the result, or continue with another tool without uploading again.

🛡️ Zero-Storage Architecture

Your files are processed in volatile RAM and never written to disk.

  • ✓ In-memory processing, memory released immediately
  • ✓ No account, no copy kept, no document logs
  • ✓ HTTPS encryption in transit

Frequently asked questions

What file size is accepted for a tax return?+

Many tax return upload portals accept files up to around 5 MB. Limits vary between organizations, so always check the maximum shown on the form.

How do I protect a tax return sent by email?+

Use Protect PDF to encrypt the file with AES-256 and share the password through another channel (SMS, phone call).

Is Merge PDF really free?+

Yes. UnboltPDF is free and unlimited: no sign-up, no watermark, no daily quota. The service is financed by advertising.

Are my files safe?+

Your files are processed in volatile memory (RAM) and are never written to a disk. The memory is released as soon as the result is sent back to you. We do not keep copies or log document contents.

What is the maximum file size?+

You can upload up to 50 MB per task, and up to 40 files for tools that accept several files.

Does it work on phones, Mac and Windows?+

Yes. Everything runs in your web browser: Chrome, Safari, Firefox and Edge on desktop, Android and iPhone. Nothing to install.

Popular uses