diff --git a/conda_smithy/feedstock_content/build-locally.py b/conda_smithy/feedstock_content/build-locally.py
index 00eeb34b1..f3d4f62fd 100755
--- a/conda_smithy/feedstock_content/build-locally.py
+++ b/conda_smithy/feedstock_content/build-locally.py
@@ -13,6 +13,7 @@
 def setup_environment(ns):
     os.environ["CONFIG"] = ns.config
     os.environ["UPLOAD_PACKAGES"] = "False"
+    os.environ["IS_PR_BUILD"] = "True"
     if ns.debug:
         os.environ["BUILD_WITH_CONDA_DEBUG"] = "1"
         if ns.output_id:
diff --git a/conda_smithy/templates/azure-pipelines-linux.yml.tmpl b/conda_smithy/templates/azure-pipelines-linux.yml.tmpl
index 08cc3144f..13aebefad 100644
--- a/conda_smithy/templates/azure-pipelines-linux.yml.tmpl
+++ b/conda_smithy/templates/azure-pipelines-linux.yml.tmpl
@@ -33,6 +33,11 @@ jobs:
 {%- if docker.run_args is defined %}
         export CONDA_FORGE_DOCKER_RUN_ARGS="{{ docker.run_args }}"
 {%- endif %}
+        if [[ "${BUILD_REASON:-}" == "PullRequest" ]]; then
+          export IS_PR_BUILD="True"
+        else
+          export IS_PR_BUILD="False"
+        fi
         .scripts/run_docker_build.sh
     displayName: Run docker build
     env:
diff --git a/conda_smithy/templates/azure-pipelines-osx.yml.tmpl b/conda_smithy/templates/azure-pipelines-osx.yml.tmpl
index 04a92dc56..cf57d1d70 100644
--- a/conda_smithy/templates/azure-pipelines-osx.yml.tmpl
+++ b/conda_smithy/templates/azure-pipelines-osx.yml.tmpl
@@ -19,6 +19,11 @@ jobs:
 {%- if upload_on_branch %}
       export UPLOAD_ON_BRANCH="{{ upload_on_branch }}"
 {%- endif %}
+      if [[ "${BUILD_REASON:-}" == "PullRequest" ]]; then
+        export IS_PR_BUILD="True"
+      else
+        export IS_PR_BUILD="False"
+      fi
       ./.scripts/run_osx_build.sh
     displayName: Run OSX build
     env:
diff --git a/conda_smithy/templates/azure-pipelines-win.yml.tmpl b/conda_smithy/templates/azure-pipelines-win.yml.tmpl
index c0f87103d..417430c33 100644
--- a/conda_smithy/templates/azure-pipelines-win.yml.tmpl
+++ b/conda_smithy/templates/azure-pipelines-win.yml.tmpl
@@ -137,4 +137,4 @@ jobs:
 {%- for secret in secrets %}
         {{ secret }}: $({{ secret }})
 {%- endfor %}
-      condition: and(succeeded(), not(eq(variables['UPLOAD_PACKAGES'], 'False')))
+      condition: and(succeeded(), not(eq(variables['UPLOAD_PACKAGES'], 'False')), not(eq(variables['Build.Reason'], 'PullRequest')))
diff --git a/conda_smithy/templates/build_steps.sh.tmpl b/conda_smithy/templates/build_steps.sh.tmpl
index 20df267d3..ed1ad0c46 100644
--- a/conda_smithy/templates/build_steps.sh.tmpl
+++ b/conda_smithy/templates/build_steps.sh.tmpl
@@ -86,7 +86,7 @@ else
 
     ( startgroup "Uploading packages" ) 2> /dev/null
 
-    if [[ "${UPLOAD_PACKAGES}" != "False" ]]; then
+    if [[ "${UPLOAD_PACKAGES}" != "False" ]] && [[ "${IS_PR_BUILD}" == "False" ]]; then
         upload_package {% if conda_forge_output_validation %}--validate --feedstock-name="${FEEDSTOCK_NAME}" {% endif %}{% if private_upload %} --private{% endif %} "${FEEDSTOCK_ROOT}" "${RECIPE_ROOT}" "${CONFIG_FILE}"
     fi
 
diff --git a/conda_smithy/templates/circle.yml.tmpl b/conda_smithy/templates/circle.yml.tmpl
index b7f239542..82746bf91 100644
--- a/conda_smithy/templates/circle.yml.tmpl
+++ b/conda_smithy/templates/circle.yml.tmpl
@@ -22,7 +22,7 @@ jobs:
     machine: true
 {%- else %}
     macos:
-      xcode: "9.0"
+      xcode: "13.0.0"
 {%- endif %}
     environment:
       - CONFIG: "{{ data.config_name }}"
@@ -43,11 +43,21 @@ jobs:
           command: |
             export CI=circle
             export FEEDSTOCK_NAME=$(basename ${CIRCLE_PROJECT_REPONAME})
+            if [[ "${CIRCLE_PR_NUMBER:-}" == "" ]]; then
+              export IS_PR_BUILD="False"
+            else
+              export IS_PR_BUILD="True"
+            fi
             ./.scripts/run_docker_build.sh
 {%- else %}
           command: |
             export CI=circle
             export FEEDSTOCK_NAME=$(basename ${CIRCLE_PROJECT_REPONAME})
+            if [[ "${CIRCLE_PR_NUMBER:-}" == "" ]]; then
+              export IS_PR_BUILD="False"
+            else
+              export IS_PR_BUILD="True"
+            fi
             ./.scripts/run_osx_build.sh
 {%- endif %}
 {%- if idle_timeout_minutes %}
diff --git a/conda_smithy/templates/drone.yml.tmpl b/conda_smithy/templates/drone.yml.tmpl
index b96da1973..b460ffc12 100644
--- a/conda_smithy/templates/drone.yml.tmpl
+++ b/conda_smithy/templates/drone.yml.tmpl
@@ -37,6 +37,7 @@ steps:
 {%- if upload_on_branch %}
     - export UPLOAD_ON_BRANCH="{{ upload_on_branch }}"
 {%- endif %}
+    - export IS_PR_BUILD=$(if [[ "$${DRONE_PULL_REQUEST:-}" == "" ]]; then echo "False"; else echo "True"; fi)
     - sed -i '$ichown -R conda:conda "$FEEDSTOCK_ROOT"' /opt/docker/bin/entrypoint
     - /opt/docker/bin/entrypoint $FEEDSTOCK_ROOT/.scripts/build_steps.sh
     - echo "Done building"
diff --git a/conda_smithy/templates/github-actions.tmpl b/conda_smithy/templates/github-actions.tmpl
index 3022fd1a1..e3bf18461 100644
--- a/conda_smithy/templates/github-actions.tmpl
+++ b/conda_smithy/templates/github-actions.tmpl
@@ -94,6 +94,11 @@ jobs:
         docker run --rm --privileged multiarch/qemu-user-static:register --reset --credential yes
         export FEEDSTOCK_NAME="$(basename $GITHUB_REPOSITORY)"
         export GIT_BRANCH="$(basename $GITHUB_REF)"
+        if [[ "${GITHUB_EVENT_NAME}" == "pull_request" ]]; then
+          export IS_PR_BUILD="True"
+        else
+          export IS_PR_BUILD="False"
+        fi
         echo "::endgroup::"
         ./.scripts/run_docker_build.sh
 
@@ -113,6 +118,11 @@ jobs:
       run: |
         export FEEDSTOCK_NAME="$(basename $GITHUB_REPOSITORY)"
         export GIT_BRANCH="$(basename $GITHUB_REF)"
+        if [[ "${GITHUB_EVENT_NAME}" == "pull_request" ]]; then
+          export IS_PR_BUILD="True"
+        else
+          export IS_PR_BUILD="False"
+        fi
         ./.scripts/run_osx_build.sh
 
 {%- for choco_pkg in choco %}
@@ -155,12 +165,19 @@ jobs:
         {%- endif %}
         set "FEEDSTOCK_NAME=%GITHUB_REPOSITORY:*/=%"
         set "GIT_BRANCH=%GITHUB_REF:refs/heads/=%"
+        if /i "%GITHUB_EVENT_NAME%" == "pull_request" (
+          set "IS_PR_BUILD=True"
+        ) else (
+          set "IS_PR_BUILD=False"
+        )
         {%- if conda_forge_output_validation %}
         validate_recipe_outputs "%FEEDSTOCK_NAME%"
         if errorlevel 1 exit 1
         {%- endif %}
         if /i "%UPLOAD_PACKAGES%" == "true" (
-          upload_package {% if conda_forge_output_validation %}--validate --feedstock-name="%FEEDSTOCK_NAME%"{% endif %}{% if private_upload %} --private{% endif %} .\ ".\{{ recipe_dir }}" .ci_support\%CONFIG%.yaml
+          if /i "%IS_PR_BUILD%" == "false" (
+            upload_package {% if conda_forge_output_validation %}--validate --feedstock-name="%FEEDSTOCK_NAME%"{% endif %}{% if private_upload %} --private{% endif %} .\ ".\{{ recipe_dir }}" .ci_support\%CONFIG%.yaml
+          )
         )
       env:
         PYTHONUNBUFFERED: 1
diff --git a/conda_smithy/templates/run_docker_build.sh.tmpl b/conda_smithy/templates/run_docker_build.sh.tmpl
index f861eb56a..6d12ead8d 100644
--- a/conda_smithy/templates/run_docker_build.sh.tmpl
+++ b/conda_smithy/templates/run_docker_build.sh.tmpl
@@ -75,12 +75,14 @@ fi
 ( startgroup "Start Docker" ) 2> /dev/null
 
 export UPLOAD_PACKAGES="${UPLOAD_PACKAGES:-True}"
+export IS_PR_BUILD="${IS_PR_BUILD:-False}"
 {{ docker.executable }} run ${DOCKER_RUN_ARGS} \
            -v "${RECIPE_ROOT}":/home/conda/recipe_root:rw,z,delegated \
            -v "${FEEDSTOCK_ROOT}":/home/conda/feedstock_root:rw,z,delegated \
            -e CONFIG \
            -e HOST_USER_ID \
            -e UPLOAD_PACKAGES \
+           -e IS_PR_BUILD \
            -e GIT_BRANCH \
            -e UPLOAD_ON_BRANCH \
            -e CI \
diff --git a/conda_smithy/templates/run_osx_build.sh.tmpl b/conda_smithy/templates/run_osx_build.sh.tmpl
index af4527767..dfe4ae369 100644
--- a/conda_smithy/templates/run_osx_build.sh.tmpl
+++ b/conda_smithy/templates/run_osx_build.sh.tmpl
@@ -81,7 +81,7 @@ exit 1
 {%- else %}
 ( startgroup "Uploading packages" ) 2> /dev/null
 
-if [[ "${UPLOAD_PACKAGES}" != "False" ]]; then
+if [[ "${UPLOAD_PACKAGES}" != "False" ]] && [[ "${IS_PR_BUILD}" == "False" ]]; then
   upload_package {% if conda_forge_output_validation %}--validate --feedstock-name="${FEEDSTOCK_NAME}"{% endif %}{% if private_upload %} --private{% endif %} ./ ./{{ recipe_dir }} ./.ci_support/${CONFIG}.yaml
 fi
 
diff --git a/conda_smithy/templates/travis.yml.tmpl b/conda_smithy/templates/travis.yml.tmpl
index 1b982b1ca..c24943f97 100644
--- a/conda_smithy/templates/travis.yml.tmpl
+++ b/conda_smithy/templates/travis.yml.tmpl
@@ -55,9 +55,10 @@ script:
 {%- if upload_on_branch %}
   - export UPLOAD_ON_BRANCH="{{ upload_on_branch }}"
 {%- endif %}
+  - if [[ "${TRAVIS_PULL_REQUEST:-}" == "false" ]]; then export IS_PR_BUILD="False"; else export IS_PR_BUILD="True"; fi
 {% if 'osx' in platformset %}
   - if [[ ${PLATFORM} =~ .*osx.* ]]; then {%- if idle_timeout_minutes %} travis_wait {{ idle_timeout_minutes }}{% endif %} ./.scripts/run_osx_build.sh; fi
 {%- endif %}
 {% if 'linux' in platformset %}
   - if [[ ${PLATFORM} =~ .*linux.* ]]; then {%- if idle_timeout_minutes %} travis_wait {{ idle_timeout_minutes }}{% endif %} ./.scripts/run_docker_build.sh; fi
-{%- endif %}
\ No newline at end of file
+{%- endif %}
diff --git a/news/is_pr_build.rst b/news/is_pr_build.rst
new file mode 100644
index 000000000..fb6a1e72f
--- /dev/null
+++ b/news/is_pr_build.rst
@@ -0,0 +1,23 @@
+**Added:**
+
+* Added explicit check to not upload packages on PR builds.
+
+**Changed:**
+
+* Updated CircleCI xcode version to 13.0.0 to prevent failures.
+
+**Deprecated:**
+
+* <news item>
+
+**Removed:**
+
+* <news item>
+
+**Fixed:**
+
+* <news item>
+
+**Security:**
+
+* <news item>