USCIS's official guidance for uploading evidence while filling out a form online in a USCIS account says files “must not be larger than 12MB in size”, must be PDF, JPG or JPEG (some forms also accept TIF/TIFF), and must not be encrypted or password-protected — that is the scope the official page documents (its separate upload-a-completed-PDF flow states no size cap there, so check your form's own instructions). The full rules, with the official source link and our verification date, are in our USCIS upload requirements entry.
Why your PDF is over 12 MB
Almost always: scanned pages. A page scanned in color at 600 DPI can be 2–4 MB on its own, so a tax return or a stack of statements blows past 12 MB quickly. Text you typed and saved as PDF is rarely the problem — a 100-page text-only PDF is usually under 2 MB.
The fix, step by step
- Open our PDF Target Size tool. It runs in your browser — your document is not uploaded to us, which matters when the document is a tax return or an ID.
- Select your PDF and choose the Under 12 MB target.
- Run the default mode first. It keeps your text and layout and recompresses the scanned images inside the PDF, which is usually enough.
- Check the verified result: the tool only reports success when the output is actually under the target.
- If the target isn't reached, you can run the stronger mode (pages become images — fine for scans, since they already are images).
Prevention for your next scan
- Scan documents at 200–300 DPI, not 600. Text stays perfectly readable.
- Use black-and-white or grayscale for text documents; reserve color for photos and IDs.
- One more USCIS rule to remember: don't password-protect the file. Bank statements often download encrypted — print-to-PDF or re-save them without the password first.
This guide covers file mechanics only. For what evidence to file, deadlines, or anything about your case, consult the USCIS instructions for your form or a qualified professional.