diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index cb9b58a4..e9bc655e 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -28,7 +28,7 @@ jobs:
     strategy:
       matrix:
         os: [ubuntu-latest]
-        scala: [2.13.12]
+        scala: [2.13.15]
         java: [graalvm@21]
     runs-on: ${{ matrix.os }}
     steps:
@@ -144,12 +144,12 @@ jobs:
             ~/Library/Caches/Coursier/v1
           key: ${{ runner.os }}-sbt-cache-v2-${{ hashFiles('**/*.sbt') }}-${{ hashFiles('project/build.properties') }}
 
-      - name: Download target directories (2.13.12)
+      - name: Download target directories (2.13.15)
         uses: actions/download-artifact@v3
         with:
-          name: target-${{ matrix.os }}-${{ matrix.java }}-2.13.12
+          name: target-${{ matrix.os }}-${{ matrix.java }}-2.13.15
 
-      - name: Inflate target directories (2.13.12)
+      - name: Inflate target directories (2.13.15)
         run: |
           tar xf targets.tar
           rm targets.tar
diff --git a/build.sbt b/build.sbt
index 48422380..38ac1fbe 100644
--- a/build.sbt
+++ b/build.sbt
@@ -9,7 +9,7 @@ ThisBuild / developers := List(
 )
 ThisBuild / versionScheme := Some("early-semver")
 ThisBuild / homepage := Some(url("https://github.com/ocadotechnology/sttp-oauth2"))
-val Scala213 = "2.13.12"
+val Scala213 = "2.13.15"
 ThisBuild / scalaVersion := Scala213
 ThisBuild / githubWorkflowJavaVersions := Seq(JavaSpec.graalvm("21"))
 ThisBuild / githubWorkflowBuild ++= Seq(