diff --git a/Dockerfile b/Dockerfile
index 49983e8d4d919aa08cf571b922ed25b60461202e..d0c91e9fe4682eb4e65a699dbddf47ea0e81358d 100644
--- a/Dockerfile
+++ b/Dockerfile
@@ -9,7 +9,7 @@ ENV TAIKO_SKIP_CHROMIUM_DOWNLOAD=true
 ENV TAIKO_BROWSER_PATH=/usr/bin/chromium-browser
 ENV TAIKO_BROWSER_ARGS=--no-sandbox,--start-maximized,--disable-dev-shm-usage,--ignore-certificate-errors
 
-ADD https://github.com/fluxcd/flux2/releases/download/v0.17.2/flux_0.17.2_linux_amd64.tar.gz /tmp/
+ADD https://github.com/fluxcd/flux2/releases/download/v0.18.3/flux_0.18.3_linux_amd64.tar.gz /tmp/
 # Download kubectl until it's packaged in alpine > 3.14
 ADD https://dl.k8s.io/release/v1.21.0/bin/linux/amd64/kubectl /usr/local/bin/
 COPY ./test/pytest/le-staging-bundle.pem /usr/local/share/ca-certificates/le-staging-bundle.pem
diff --git a/docs/installation/install_oas.rst b/docs/installation/install_oas.rst
index e1ba28876864091acf84091310e02f6d922e1ca9..4ce865809a105f621117437641b83054b21c447c 100644
--- a/docs/installation/install_oas.rst
+++ b/docs/installation/install_oas.rst
@@ -53,7 +53,7 @@ Prerequisites
 -------------
 
 - ``kubectl`` (`installation instructions <https://kubernetes.io/docs/tasks/tools/#kubectl>`__)
-- ``flux version 0.17.2`` `Download flux_0.17.2_linux_amd64.tar.gz <https://github.com/fluxcd/flux2/releases/download/v0.17.2/flux_0.17.2_linux_amd64.tar.gz>`_
+- ``flux version 0.18.3`` `Download flux_0.18.3_linux_amd64.tar.gz <https://github.com/fluxcd/flux2/releases/download/v0.18.3/flux_0.18.3_linux_amd64.tar.gz>`_
 
 Copy the file ``install/.flux.env.example`` to your cluster dir
 ``clusters/oas.example.org/.flux.env``. This file contains the last bit of
diff --git a/install/flux-version-check.sh b/install/flux-version-check.sh
index e88e635e78ba893b2495060744bb64b72dc88e55..779c14507f9c399a6ad7c5cc30e574649145c371 100644
--- a/install/flux-version-check.sh
+++ b/install/flux-version-check.sh
@@ -1,4 +1,6 @@
-if [ "$(flux --version)" != "flux version 0.17.2" ]; then
-    echo "The OpenAppStack installation only works with Flux version 0.17.2"
-    exit 1;
+#!/usr/bin/env bash
+
+if [ "$(flux --version)" != "flux version 0.18.3" ]; then
+  echo "The OpenAppStack installation only works with Flux version 0.18.3"
+  exit 1
 fi