diff --git a/.github/workflows/ci-build.yaml b/.github/workflows/ci-build.yaml
index 688bbe3f84c7..259489720fbc 100644
--- a/.github/workflows/ci-build.yaml
+++ b/.github/workflows/ci-build.yaml
@@ -225,15 +225,15 @@ jobs:
             profile: minimal
             useApi: true
           - test: test-executor
-            install_k3s_version: v1.28.11+k3s1
+            install_k3s_version: v1.28.13+k3s1
             profile: minimal
             useApi: false
           - test: test-corefunctional
-            install_k3s_version: v1.28.11+k3s1
+            install_k3s_version: v1.28.13+k3s1
             profile: minimal
             useApi: false
           - test: test-functional
-            install_k3s_version: v1.28.11+k3s1
+            install_k3s_version: v1.28.13+k3s1
             profile: minimal
             useApi: false
     steps:
@@ -260,7 +260,7 @@ jobs:
       - name: Install and start K3S
         run: |
           if ! echo "${{ matrix.install_k3s_version }}" | egrep '^v[0-9]+\.[0-9]+\.[0-9]+\+k3s1$'; then
-            export INSTALL_K3S_VERSION=v1.30.2+k3s1
+            export INSTALL_K3S_VERSION=v1.31.0+k3s1
           else
             export INSTALL_K3S_VERSION=${{ matrix.install_k3s_version }}
           fi
diff --git a/docs/releases.md b/docs/releases.md
index 4ebd5cd06ead..125ba9557e74 100644
--- a/docs/releases.md
+++ b/docs/releases.md
@@ -40,10 +40,11 @@ Otherwise, we typically release every two weeks:
 
 ## Kubernetes Compatibility Matrix
 
-| Argo Workflows \ Kubernetes | 1.28 | 1.29 | 1.30 |
-|-----------------------------|------|------|------|
-| **3.5**                     | `✓`  | `✓`  | `✓`  |
-| **3.4**                     | `?`  | `?`  | `?`  |
+| Argo Workflows \ Kubernetes | 1.28 | 1.29 | 1.30 | 1.31 |
+|-----------------------------|------|------|------|------|
+| **main**                    | `✓`  | `✓`  | `✓`  | `✓`  |
+| **3.5**                     | `✓`  | `✓`  | `✓`  | `?`  |
+| **3.4**                     | `?`  | `?`  | `?`  | `?`  |
 
 * `✓` Fully supported versions.
 * `?` Due to breaking changes might not work. Also, we haven't thoroughly tested against this version.
@@ -57,4 +58,4 @@ Note that Kubernetes [is backward compatible with clients](https://github.com/ku
 The caveats with newer k8s versions are possible changes to experimental APIs and unused new features.
 Argo uses stable Kubernetes APIs such as Pods and ConfigMaps; see the Controller and Server RBAC of your [installation](installation.md) for a full list.
 
-The `main` branch is currently [tested on Kubernetes 1.28](https://github.com/argoproj/argo-workflows/blob/main/.github/workflows/ci-build.yaml#L218) and [1.30](https://github.com/argoproj/argo-workflows/blob/main/.github/workflows/ci-build.yaml#L250).
+The `main` branch is currently [tested on Kubernetes 1.28](https://github.com/argoproj/argo-workflows/blob/main/.github/workflows/ci-build.yaml#L228) and [1.31](https://github.com/argoproj/argo-workflows/blob/main/.github/workflows/ci-build.yaml#L263).