Pnas Cover Letter Guidelines Examples

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PNAS Author Center


Initial Submission

All authors must submit their papers at PNAS. Only a single PDF file containing all text, figures, tables, and supplemental information (SI) is required for initial submissions; high-resolution files are not required. The corresponding author must include the following information for each coauthor: author order, first name, last name, email, and institution. A cover letter (optional), movie files, and datasets may be uploaded separately.

A length estimate is not required for initial submissions, but 6-page articles should be under 49,000 characters (including spaces, figures, and tables) and 10-page articles under 82,000. Direct Submission Plus and Contributed Plus submissions undergo the same review process as Direct Submissions and Contributed Submissions respectively. Authors writing their papers in LaTeX should use our LaTeX template. Authors will need to complete the License to Publish form and provide permissions for any previously published material.


Manuscript Length

PNAS generally uses a two-column format averaging 67 characters, including spaces, per line. The maximum length of a regular research article is 6 pages (or 10 pages for Direct Submission Plus and Contributed Plus articles), including all text, spaces, and the number of characters displaced by figures, tables, and equations.

An online submission tool estimates whether the manuscript fits within PNAS length requirements (see Length Estimate Guidelines and FAQ). When submitting tables, figures, and/or equations in addition to text, keep the text for your manuscript under 39,000 characters (including spaces) for 6-page articles and 65,000 for 10-page articles.


Digital Figures

High-resolution figure files are not required for initial submissions. Resolution of at least 300 dpi for all figures is required. EPS, high-resolution PDF, and PowerPoint are preferred formats for figures that will be used in the main text. Authors may submit PRC or U3D files for 3D images; these must be accompanied by 2D representations in TIFF, EPS, or high-resolution PDF format. (See SI below for supplementary material.) Color images must be in RGB (red, green, blue) mode. Include the font files for any text.

Images must be final size, preferably one column width (8.7 cm). Figures wider than one column should be sized to 11.4 cm or 17.8 cm wide. Numbers, letters, and symbols should be no smaller than 6 points (2 mm) and no larger than 12 points (6 mm) after reduction and must be consistent. Composite figures must be preassembled. Figures must be submitted as separate files, not embedded in manuscript text. See the PNAS Digital Art Guidelines. Figures and tables may be enlarged to improve legibility of text.



Each table should have a brief title above the table. Table footnotes should be below the table. Tables must be submitted as separate files, not embedded in the manuscript text. Publication-ready formats include Word and LaTeX.



The main text of the paper must stand on its own without the SI. Refer to SI in the manuscript at an appropriate point in the text. Number supporting figures and tables starting with S1, S2, etc. Authors are limited to no more than 10 SI files, not including movie files.

Authors who place detailed materials and methods in SI must provide sufficient detail in the main text methods to enable a reader to follow the logic of the procedures and results and also must reference the online methods. If a paper is fundamentally a study of a new method or technique, then the methods must be described completely in the main text.

Because PNAS edits SI and composes it into a single PDF, authors must provide the following file formats only:

  • Text: Supply Word, RTF, or LaTeX files (LaTeX files must be accompanied by a PDF with the same file name for visual reference).
  • Figures: Provide a brief legend for each supporting figure after the supporting text. Provide figure images in TIFF, EPS, PowerPoint, high-resolution PDF, JPEG, or GIF format; figures may not be embedded in manuscript text. When saving TIFF files, use only LZW compression; do not use JPEG compression. Do not save figure numbers, legends, or author names as part of the image. Composite figures must be preassembled.
  • 3D Figures: Supply a composable U3D or PRC file so that it may be edited and composed. Authors may submit a PDF file which will be published in raw format and will not be edited or composed.
  • Tables: Supply Word, RTF, or LaTeX files (LaTeX files must be accompanied by a PDF with the same file name for visual reference); include only one table per file. Do not use tabs or spaces to separate columns in Word tables. Tables should contain a minimum of two columns and two rows. Each column should include a column heading.
  • Datasets: Supply Excel (.xls), RTF, PDF, CSV, or TXT files. This file type will be published in raw format and will not be edited or composed.
  • Movies: Supply Audio Video Interleave (avi), Quicktime (mov), Windows Media (wmv), animated GIF (gif), or MPEG files and submit a brief legend for each movie in a Word or RTF file. All movies should be submitted at the desired reproduction size and length. Movies should be no more than 10 MB in size.
  • Still Images: Authors must provide a still image from each video file. Supply TIFF, EPS, high-resolution PDF, JPEG, or GIF files.
  • Appendices: PNAS prefers that authors submit individual source files to ensure readability. If this is not possible, supply a single PDF file that contains all of the SI associated with the paper. This file type will be published in raw format and will not be edited or composed.


Revised and Contributed Submission

Authors of Contributed papers, and authors of revisions, or resubmissions must provide publication-ready source files; guidelines for submitting source files appear below. Publication-ready file formats include Word and LaTeX. Only one paper text file should be submitted. SI text files should be uploaded separately. Figures and tables should not be included in main or SI text files. At the completion of the review process for Contributed papers, the NAS member may designate a corresponding author to upload submission files.

How to submit your revised or resubmitted submission to PNAS

Revised papers must be received within 2 months or they will be treated as new submissions. If you require additional time, please notify PNAS. Multiple revisions are rarely permitted, and there is no guarantee that revised papers will be accepted.

Please consider the following when preparing revised submissions.

Resubmission/Revision Cover Letter

The cover letter should include a point-by-point response to the comments of the reviewers and editor. A detailed description of all changes made is required before PNAS can process the revision.

Manuscript Files

Files must be in production-ready format and should not include any embedded figures, tables, or schemes. Text files should be provided in Word, RTF, or LaTeX format. Figures and schemes should be uploaded individually in TIFF, EPS, PPT, or high-resolution PDF. Tables should also be uploaded individually in Word, RTF, or LaTeX format. SI should be designated as such using the file type and file format options in the "Add File" screen of the submission process. SI is required to be uploaded separately similarly to the main text files.

Please supply high-resolution files whenever possible. Resolution of at least 1200 dpi is needed for all line art, 600 dpi for images that combine line art with photographs/halftones, and 300 dpi for color or grayscale photographic images. Please review the PNAS Digital Art Guidelines.

When a revision is submitted to PNAS, all files must be in their final form.

Journal Cover Figures

Authors are invited to submit scientifically interesting and visually arresting cover images (see our archive). Illustrations need not be reprinted in the article but should be representative of the work. Images should be original, and authors grant PNAS a license to publish. Include a brief lay-language caption (50–60 words) and credit information (e.g., Image courtesy of...). Images should be 21 cm wide by 22.5 cm high. Files should be EPS or TIFF and should be in RGB color mode. Cover figure files may be submitted online when the paper is submitted or may be sent to; contact PNAS for instructions on submitting large files. Submissions provided outside the online submission system should include manuscript number, author name, phone, and email.

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ARC Home | Finishing touches

Writing a Journal Cover Letter [Free Template]

Also available in: 한국어日本語中文portuguêsespañol


The cover letter you submit to your target journal is your chance to lobby on behalf of your manuscript. Here are some tips for getting it right, plus a free journal cover letter template.

The cover letter accompanying your journal submission is your chance to lobby on behalf of your manuscript. The letter is far from just a formality and should be written with the same care as your manuscript’s text (if not more). Ultimately, your cover letter is designed to influence the decision of the editor to send your manuscript out for peer review. The letter will argue that your manuscript is a good fit for the journal you are submitting it to and highlight your most important findings. This post contains some tips, which can also be found in our downloadable resources:

1.Instructions on writing a journal cover letter

2.Microsoft Word cover letter template (also available with instructions in Chinese, Japanese, Korean, Portuguese, and Spanish)

You should also assure the editor that there are no conflicts of interest that would affect the decision to publish your manuscript. In the end, your cover letter should interest the editor enough to read your paper carefully and choose to send it for peer review.

Getting ready to resubmit your revised manuscript? Read our tips on responding to peer reviewers

A cover letter should be written like a standard business letter:

Address the editor formally by name, if known. Include your contact information, as well. This information is probably available through the journal’s online submission system, but it is proper to provide it in the cover letter, too.

Begin your cover letter with a paragraph that states the name of the manuscript and the names of the authors. You can also describe what type of manuscript your submission is (research article, review, case report, etc.). In this first paragraph and the next, describe the rationale behind your study and the major findings from your research. You can refer to prior work that you have published if it is directly related.

Next, write a short paragraph that explains why your manuscript would be a good fit for the journal. Do not simply state that your manuscript is “of interest to the field” or “novel.” Address specific aspects of the journal’s Aims & Scope statement. If the journal expresses interest in research with a clinical application, be sure to highlight the importance of your work in terms of clinical implications. If the journal mentions that it focuses on nanostructured materials, explain how your work involved such materials. Even if your work is not a perfect fit for the journal, be sure to address some of the Aims & Scope statement, and explain why your manuscript would be of interest to the journal’s readers.

Finally, close with a brief paragraph indicating the following:

  • The manuscript is original (i.e., you wrote it, not copied it)
  • No part of the manuscript has been published before, nor is any part of it under consideration for publication at another journal
  • There are no conflicts of interest to disclose
  • A list of potential reviewers (only if requested by the journal)
  • Any researchers who should NOT review your manuscript

Together, this information provides assurance to the editor that your manuscript merits consideration for publication in their journal and that you are interested specifically in their journal. Sometimes great science will be reviewed regardless of the cover letter, but a well written cover letter is useful for the vast majority of scientists who want to make their research stand out.

Best of luck with your research! If you have any questions about your cover letter, write us anytime.

Journal Cover Letter Templates

Click here to download a Microsoft Word template for a standard journal cover letter (also available with instructions in Chinese, Japanese, Korean, Portuguese, and Spanish). A full set of the information in this post can be found here.

TagsFinishing touchesPublishing processCommunicating with editorsJournal editorsJournal submissionPeer reviewCover letterBack to School seriesDownloadables


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