What are PLAN files and how to open them

Are you having problems opening a PLAN file or just wondering what they contain? We explain what these files are used for and show you software that we know can open or otherwise handle your files.

What is a PLAN file?

PLAN files have multiple uses, and Chief Architect Plan is one of them. Read more about the other uses further down the page.

Chief Architect Plan

We have not yet analyzed in detail what these files contain and what they are used for. We're working on it.

How to open PLAN files

Important: Different programs may use files with the PLAN file extension for different purposes, so unless you are sure which format your PLAN file is, you may need to try a few different programs.

While we have not verified the apps ourselves yet, our users have suggested ten different PLAN openers which you will find listed below.

Last updated: December 14, 2021

More file formats using the PLAN extension

Through our research of PLAN files, we know that the following formats exist. However, we have not yet analyzed them in detail.

  • Home Designer Plan
  • MaxiPlan Spreadsheet

Various apps that use files with this extension

These apps are known to open certain types of PLAN files. Remember, different programs may use PLAN files for different purposes, so you may need to try out a few of them to be able to open your specific file.

Help us help others helps thousands of users every day, and we would love to hear from you if you have additional information about PLAN file formats, example files, or compatible programs. Please use the links below or email us at to discuss further.