diff --git a/.github/workflows/archery.yml b/.github/workflows/archery.yml
index b7321a7f65d..0bc88faea55 100644
--- a/.github/workflows/archery.yml
+++ b/.github/workflows/archery.yml
@@ -49,7 +49,9 @@ jobs:
           fetch-depth: 0
       - name: Git Fixup
         shell: bash
-        run: git branch master origin/master || true
+        run: |
+          DEFAULT_BRANCH=${{ github.event.repository.default_branch }}
+          git branch $DEFAULT_BRANCH origin/$DEFAULT_BRANCH || true
       - name: Setup Python
         uses: actions/setup-python@v1
         with:
diff --git a/.github/workflows/comment_bot.yml b/.github/workflows/comment_bot.yml
index 3d89c532267..989becb979e 100644
--- a/.github/workflows/comment_bot.yml
+++ b/.github/workflows/comment_bot.yml
@@ -57,16 +57,17 @@ jobs:
     runs-on: ubuntu-latest
     steps:
       - uses: actions/checkout@v2
-      - uses: r-lib/actions/pr-fetch@master
+      - uses: r-lib/actions/pr-fetch@v2
         with:
           repo-token: ${{ secrets.GITHUB_TOKEN }}
       - name: See what is different
         run: |
           set -ex
+          DEFAULT_BRANCH=${{ github.event.repository.default_branch }}
           git remote add upstream https://github.com/apache/arrow
           git fetch upstream
           changed() {
-            git diff --name-only HEAD..upstream/master | grep -e "$1" >/dev/null 2>&1
+            git diff --name-only HEAD..upstream/$DEFAULT_BRANCH | grep -e "$1" >/dev/null 2>&1
           }
           if changed '^r/.*\.R$'; then
             echo "R_DOCS=true" >> $GITHUB_ENV
@@ -115,7 +116,7 @@ jobs:
               --clang_format_binary=clang-format-${CLANG_TOOLS} \
               --exclude_glob=cpp/build-support/lint_exclusions.txt \
               --source_dir=r/src --quiet --fix
-      - uses: r-lib/actions/setup-r@v1
+      - uses: r-lib/actions/setup-r@v2
         if: env.R_DOCS == 'true' || env.R_CODE == 'true' || endsWith(github.event.comment.body, 'everything')
       - name: Update R docs
         if: env.R_DOCS == 'true' || endsWith(github.event.comment.body, 'everything')
@@ -131,7 +132,7 @@ jobs:
         if: env.R_CODE == 'true' || endsWith(github.event.comment.body, 'everything')
         shell: Rscript {0}
         run: |
-          changed_files <- system("git diff --name-only HEAD..upstream/master 2>&1", intern = TRUE)
+          changed_files <- system("git diff --name-only HEAD..upstream/${{ github.event.repository.default_branch }} 2>&1", intern = TRUE)
           # only grab the .R files under r/
           changed_files <- grep('^r/.*\\.R$', changed_files, value = TRUE)
           # remove latin1 which is unstylable due to encoding and codegen.R which is unique
@@ -145,7 +146,7 @@ jobs:
           git config user.name "$(git log -1 --pretty=format:%an)"
           git config user.email "$(git log -1 --pretty=format:%ae)"
           git commit -a -m 'Autoformat/render all the things [automated commit]' || echo "No changes to commit"
-      - uses: r-lib/actions/pr-push@master
+      - uses: r-lib/actions/pr-push@v2
         with:
           repo-token: ${{ secrets.GITHUB_TOKEN }}
 
@@ -155,18 +156,18 @@ jobs:
     runs-on: ubuntu-latest
     steps:
       - uses: actions/checkout@v2
-      - uses: r-lib/actions/pr-fetch@master
+      - uses: r-lib/actions/pr-fetch@v2
         with:
           repo-token: ${{ secrets.GITHUB_TOKEN }}
-      - name: Rebase on ${{ github.repository }} master
+      - name: Rebase on ${{ github.repository }} default branch
         run: |
           set -ex
           git config user.name "$(git log -1 --pretty=format:%an)"
           git config user.email "$(git log -1 --pretty=format:%ae)"
           git remote add upstream https://github.com/${{ github.repository }}
-          git fetch --unshallow upstream master
-          git rebase upstream/master
-      - uses: r-lib/actions/pr-push@master
+          git fetch --unshallow upstream ${{ github.event.repository.default_branch }}
+          git rebase upstream/${{ github.event.repository.default_branch }}
+      - uses: r-lib/actions/pr-push@v2
         with:
           repo-token: ${{ secrets.GITHUB_TOKEN }}
           args: "--force"
diff --git a/.github/workflows/dev_pr.yml b/.github/workflows/dev_pr.yml
index 86a5c98f8a6..8a9487b4edc 100644
--- a/.github/workflows/dev_pr.yml
+++ b/.github/workflows/dev_pr.yml
@@ -22,6 +22,7 @@ on:
   # push:
   #   branches:
   #     - master
+  #     - main
   pull_request_target:
     types:
       - opened
diff --git a/.github/workflows/r.yml b/.github/workflows/r.yml
index c60e3fa4142..37bdea8f6ab 100644
--- a/.github/workflows/r.yml
+++ b/.github/workflows/r.yml
@@ -200,12 +200,12 @@ jobs:
           restore-keys: r-${{ matrix.config.rtools }}-ccache-mingw-
       # We use the makepkg-mingw setup that is included in rtools40 even when
       # we use the rtools35 compilers, so we always install R 4.0/Rtools40
-      - uses: r-lib/actions/setup-r@master
+      - uses: r-lib/actions/setup-r@v2
         with:
           r-version: "4.1"
           rtools-version: 40
           Ncpus: 2
-      - uses: r-lib/actions/setup-r@master
+      - uses: r-lib/actions/setup-r@v2
         if: ${{ matrix.config.rtools == 35 }}
         with:
           rtools-version: 35
@@ -303,13 +303,13 @@ jobs:
           path: ccache
           key: r-${{ matrix.rtools }}-ccache-mingw-${{ hashFiles('cpp/**') }}
           restore-keys: r-${{ matrix.rtools }}-ccache-mingw-
-      - uses: r-lib/actions/setup-r@master
+      - uses: r-lib/actions/setup-r@v2
         if: ${{ matrix.rtools == 40 }}
         with:
           r-version: "4.1"
           rtools-version: 40
           Ncpus: 2
-      - uses: r-lib/actions/setup-r@master
+      - uses: r-lib/actions/setup-r@v2
         if: ${{ matrix.rtools == 35 }}
         with:
           rtools-version: 35
@@ -327,7 +327,7 @@ jobs:
       - name: Install cpp11 (on R 3.6)
       # Since we force installation of binary packages below, dependency versions
       # are frozen for old versions of R. We need newer cpp11 than is available as
-      # "binary" (though it doesn't matter because the cpp11 R package is just a 
+      # "binary" (though it doesn't matter because the cpp11 R package is just a
       # vehicle for the header-only C++ code.
         if: ${{ matrix.rtools == 35 }}
         shell: Rscript {0}
diff --git a/ci/detect-changes.py b/ci/detect-changes.py
index 14e71ed48ce..7669639ecd3 100644
--- a/ci/detect-changes.py
+++ b/ci/detect-changes.py
@@ -135,7 +135,7 @@ def list_github_actions_affected_files():
     """
     # GitHub Actions checkout `refs/remotes/pull/$PR/merge` where `HEAD` points
     # to the merge commit while `HEAD^` points to the commit before. Hence,
-    # `..HEAD^` points to all commit between master and the PR.
+    # `..HEAD^` points to all commit between the default branch and the PR.
     return list_affected_files("HEAD^..")
 
 
@@ -228,9 +228,9 @@ def run_from_travis():
     perr("Environment variables (excerpt):")
     dump_env_vars('TRAVIS_', '(BRANCH|COMMIT|PULL)')
     if (os.environ['TRAVIS_REPO_SLUG'] == 'apache/arrow' and
-            os.environ['TRAVIS_BRANCH'] == 'master' and
+            os.environ['TRAVIS_BRANCH'] in ['master', 'main'] and
             os.environ['TRAVIS_EVENT_TYPE'] != 'pull_request'):
-        # Never skip anything on master builds in the official repository
+        # Never skip anything on default-branch builds in the official repo
         affected = dict.fromkeys(ALL_TOPICS, True)
     else:
         desc = get_travis_commit_description()
diff --git a/ci/scripts/install_kartothek.sh b/ci/scripts/install_kartothek.sh
index 4d88943b6a9..b715f5cf849 100755
--- a/ci/scripts/install_kartothek.sh
+++ b/ci/scripts/install_kartothek.sh
@@ -28,9 +28,7 @@ karthothek=$1
 target=$2
 
 git clone --recurse-submodules https://github.com/JDASoftwareGroup/kartothek "${target}"
-if [ "${kartothek}" = "master" ]; then
-  git -C "${target}" checkout master;
-elif [ "${kartothek}" = "latest" ]; then
+if [ "${kartothek}" = "latest" ]; then
   git -C "${target}" checkout $(git describe --tags);
 else
   git -C "${target}" checkout ${kartothek};
diff --git a/ci/scripts/install_turbodbc.sh b/ci/scripts/install_turbodbc.sh
index 3e644a3e27a..e9ac26c2cc8 100755
--- a/ci/scripts/install_turbodbc.sh
+++ b/ci/scripts/install_turbodbc.sh
@@ -28,9 +28,7 @@ turbodbc=$1
 target=$2
 
 git clone --recurse-submodules https://github.com/blue-yonder/turbodbc "${target}"
-if [ "${turbodbc}" = "master" ]; then
-  git -C "${target}" checkout master;
-elif [ "${turbodbc}" = "latest" ]; then
+if [ "${turbodbc}" = "latest" ]; then
   git -C "${target}" checkout $(git describe --tags);
 else
   git -C "${target}" checkout ${turbodbc};
diff --git a/ci/scripts/python_benchmark.sh b/ci/scripts/python_benchmark.sh
index 3a35298dc04..8c4ebfc89cb 100755
--- a/ci/scripts/python_benchmark.sh
+++ b/ci/scripts/python_benchmark.sh
@@ -32,7 +32,8 @@ export PYARROW_WITH_GANDIVA=0
 
 pushd $ARROW_PYTHON_DIR
 # Workaround for https://github.com/airspeed-velocity/asv/issues/631
-git fetch --depth=100 origin master:master
+DEFAULT_BRANCH=$(git rev-parse --abbrev-ref origin/HEAD | sed s@origin/@@)
+git fetch --depth=100 origin $DEFAULT_BRANCH:$DEFAULT_BRANCH
 # Generate machine information (mandatory)
 asv machine --yes
 # Run benchmarks on the changeset being tested