CM/ECF PDF Requirements: Format, Size Limits, and Common Errors

CM/ECF is the federal judiciary's electronic filing system. Every document you submit through it must be a PDF — but not just any PDF. Here's what your files need to look like, how big they can be, and what to do when CM/ECF rejects them.

Basic PDF Requirements

Across all federal districts, CM/ECF requires that electronically filed documents meet these baseline requirements:

Format: All documents must be in PDF format with a .pdf file extension. CM/ECF does not accept Word documents, images, or any other file type.

No embedded code: PDFs cannot contain JavaScript, executable code, multimedia, or external links that trigger actions. CM/ECF scans uploads and will reject files that contain these elements.

No security restrictions: PDFs must not be password-protected or have security settings that restrict copying, printing, or reading. Remove all Adobe security features before filing.

Flattened forms: If your PDF was created from a fillable form, it must be "flattened" before filing. An unflattened form still contains editable fields, which CM/ECF may reject. To flatten, print the form to PDF rather than saving it directly.

Paper size: Documents should be formatted for U.S. Letter size (8.5 × 11 inches). While CM/ECF technically accepts other sizes, Letter is the standard across virtually all federal courts and ensures your document displays correctly.

File Size Limits

This is where it gets complicated. There is no single federal file size limit — each district court sets its own maximum. The limits range from 30 MB to 200 MB per individual PDF file.

If your district isn't listed above, use the PACER CM/ECF Court Lookup to find your court's specific requirements. When in doubt, 30 MB per file is a safe target that works everywhere.

Common CM/ECF Rejection Errors

When CM/ECF rejects your PDF, it usually displays an error message. Here are the most common ones and how to fix them:

"Document is malformed or contains code"

Your PDF contains JavaScript, form fields, or embedded scripts. Fix: open the file in any PDF viewer and print it to a new PDF. This strips out all interactive elements and produces a clean, flat file.

"File exceeds the maximum size"

Your PDF is larger than the district's per-file limit. Fix: split the PDF into multiple smaller files and upload them as separate attachments. Label them clearly — for example, Exhibit A Part 1, Exhibit A Part 2. Reduce scanned image resolution to 300 DPI and use black-and-white scanning for text documents.

"Document has security features enabled"

Your PDF has password protection or access restrictions. Fix: open the PDF in Acrobat or any PDF editor, go to security settings, and remove all restrictions. Then save and re-upload.

"File does not have a .pdf extension"

The filename doesn't end in .pdf. This can happen when files are renamed or when a non-PDF file was given a PDF extension. Fix: make sure the file is actually a PDF (not a renamed .doc or .jpg), and that the filename ends in .pdf.

Text-Searchable PDFs

Some districts require all PDFs to be text-searchable. A text-searchable PDF allows you to highlight and search for specific words within the document. This is different from an image-based PDF where the text appears as a picture.

PDFs created by saving from a word processor (like Microsoft Word or Google Docs) are automatically text-searchable. PDFs created by scanning paper documents or converting images are not — they're image-based.

For exhibit images like photographs, receipts, and screenshots, courts generally accept image-based PDFs since there's no text to make searchable. But for scanned text documents (like printed contracts or medical records), you may need to apply OCR (optical character recognition) to make the text searchable. Adobe Acrobat, Foxit, and several free tools can do this.

Scanning Best Practices

If you're scanning paper documents to convert them to PDF for filing, these settings will produce files that courts accept without issues: scan at 300 DPI resolution (this is what most districts specify as the standard), use black and white mode for text documents to minimize file size, and only use color scanning when the color is essential to the exhibit (photographs, highlighted documents, etc.).

A single-page black-and-white scan at 300 DPI typically produces a file around 50-100 KB. A color scan of the same page can be 500 KB to 2 MB. Over dozens of pages, this adds up fast.

Bookmarks

Some courts require (and all courts appreciate) bookmarks in long PDF filings. Bookmarks create a clickable navigation panel on the left side of the PDF that lets judges and clerks jump to specific sections or exhibits. If your filing has multiple exhibits or sections exceeding 20-30 pages, adding bookmarks is strongly recommended. This typically requires Acrobat or a similar PDF editor.

Privacy Redaction

Federal Rule of Civil Procedure 5.2 requires that you redact certain personal information from all court filings. Before uploading any PDF to CM/ECF, make sure it does not contain: full Social Security numbers (use last four digits only), full dates of birth (use year only), names of minors (use initials only), or complete financial account numbers (use last four digits only).

This applies to all documents — including exhibits, attachments, and images. If your exhibit photographs contain visible account numbers or birth dates, you must redact them before filing.