diff --git a/.github/PULL_REQUEST_TEMPLATE.md b/.github/PULL_REQUEST_TEMPLATE.md
index 6fedbf080..2746cd73d 100644
--- a/.github/PULL_REQUEST_TEMPLATE.md
+++ b/.github/PULL_REQUEST_TEMPLATE.md
@@ -1,4 +1,4 @@
-<!-- Thanks for contributing code! Please include a description of your change and check your PR against the list below. For further questions, refer to the contributing guide (https://github.com/Cantera/cantera/blob/master/CONTRIBUTING.md). -->
+<!-- Thanks for contributing code! Please include a description of your change and check your PR against the list below. For further questions, refer to the contributing guide (https://github.com/Cantera/cantera/blob/main/CONTRIBUTING.md). -->
 
 **Checklist**
 
diff --git a/.github/SUPPORT.md b/.github/SUPPORT.md
index fe2c98d29..7c0082500 100644
--- a/.github/SUPPORT.md
+++ b/.github/SUPPORT.md
@@ -1,6 +1,6 @@
 # How to get support
 
-> This project has a [Code of Conduct](https://github.com/Cantera/cantera/blob/master/CODE_OF_CONDUCT.md).
+> This project has a [Code of Conduct](https://github.com/Cantera/cantera/blob/main/CODE_OF_CONDUCT.md).
 > By interacting with this repository, organisation, or community you agree to
 > abide by its terms.
 
@@ -35,4 +35,4 @@ Cantera](https://cantera.org/documentation/dev-docs.html) is also available.
 
 ## Contributions
 
-See [`CONTRIBUTING.md`](https://github.com/Cantera/cantera/blob/master/CONTRIBUTING.md) on how to contribute.
+See [`CONTRIBUTING.md`](https://github.com/Cantera/cantera/blob/main/CONTRIBUTING.md) on how to contribute.
diff --git a/.github/workflows/main.yml b/.github/workflows/main.yml
index d729854af..ea74357e7 100644
--- a/.github/workflows/main.yml
+++ b/.github/workflows/main.yml
@@ -5,14 +5,14 @@ on:
     # Build on tags that look like releases
     tags:
       - v*
-    # Build when master or testing is pushed to
+    # Build when main or testing is pushed to
     branches:
-      - master
+      - main
       - testing
   pull_request:
-    # Build when a pull request targets master
+    # Build when a pull request targets main
     branches:
-      - master
+      - main
 
 jobs:
   ubuntu-multiple-pythons:
@@ -138,13 +138,13 @@ jobs:
       # machine that has previously logged in to cantera.org and trusts
       # that it logged in to the right machine
       - name: Set up SSH key and host for deploy
-        if: github.event_name == 'push' && github.repository_owner == 'Cantera' && github.ref == 'master'
+        if: github.event_name == 'push' && github.repository_owner == 'Cantera' && github.ref == 'main'
         uses: shimataro/ssh-key-action@v2
         with:
           key: ${{ secrets.CTDEPLOY_KEY }}
           known_hosts: ${{ secrets.CTDEPLOY_HOST }}
       - name: Upload the docs
-        if: github.event_name == 'push' && github.repository_owner == 'Cantera' && github.ref == 'master'
+        if: github.event_name == 'push' && github.repository_owner == 'Cantera' && github.ref == 'main'
         env:
           RSYNC_USER: "ctdeploy"
           RSYNC_SERVER: "cantera.org"
diff --git a/CONTRIBUTING.md b/CONTRIBUTING.md
index e8b1913bd..6bc0c6768 100644
--- a/CONTRIBUTING.md
+++ b/CONTRIBUTING.md
@@ -7,7 +7,7 @@
   future development
 * Fork the `Cantera/cantera` repository on Github
 * Clone your new repository or add it as a remote to an existing repository
-* Check out the existing `master` branch, then start a new feature branch for
+* Check out the existing `main` branch, then start a new feature branch for
   your work
 * When making changes, write code that is consistent with the surrounding code
   (see the [style guidelines](#style-guidelines) below)
@@ -26,8 +26,8 @@
   * Use Git's history-rewriting features (i.e., `git rebase -i`; see
     https://help.github.com/articles/about-git-rebase/) to organize your commits
     and squash "fixup" commits and reversions.
-  * Do not merge your branch with `master`. If needed, you should rebase your branch
-    onto the most recent `HEAD` commit of `master`.
+  * Do not merge your branch with `main`. If needed, you should rebase your branch
+    onto the most recent `HEAD` commit of `main`.
   * Periodically run the test suite (`scons test`) to make sure that your
     changes are not causing any test failures.
 * Push the changes on your new feature branch to your forked copy of the
@@ -40,7 +40,7 @@
   http://matplotlib.org/devel/gitwash/development_workflow.html and
   https://docs.scipy.org/doc/numpy-1.15.0/dev/gitwash/development_workflow.html
 * Cantera is licensed under a [BSD
-  license](https://github.com/Cantera/cantera/blob/master/License.txt) which
+  license](https://github.com/Cantera/cantera/blob/main/License.txt) which
   allows others to freely modify the code, and if your Pull Request is accepted,
   then that code will be release under this license as well. The copyright for
   Cantera is held collectively by the contributors. If you have made a
diff --git a/README.rst b/README.rst
index aca1f2aca..e49151165 100644
--- a/README.rst
+++ b/README.rst
@@ -158,8 +158,8 @@ development of Cantera through NumFOCUS.
 .. |doi| image:: https://zenodo.org/badge/DOI/10.5281/zenodo.170284.svg
    :target: https://doi.org/10.5281/zenodo.1174508
 
-.. |codecov| image:: https://img.shields.io/codecov/c/github/Cantera/cantera/master.svg
-   :target: https://codecov.io/gh/Cantera/cantera?branch=master
+.. |codecov| image:: https://img.shields.io/codecov/c/github/Cantera/cantera/main.svg
+   :target: https://codecov.io/gh/Cantera/cantera?branch=main
 
 .. |release| image:: https://img.shields.io/github/release/cantera/cantera.svg
    :target: https://github.com/Cantera/cantera/releases