diff --git a/var/spack/repos/builtin/packages/pika-algorithms/package.py b/var/spack/repos/builtin/packages/pika-algorithms/package.py
index 2356537a5f7..3387dfdb273 100644
--- a/var/spack/repos/builtin/packages/pika-algorithms/package.py
+++ b/var/spack/repos/builtin/packages/pika-algorithms/package.py
@@ -25,7 +25,7 @@ class PikaAlgorithms(CMakePackage):
     generator("ninja")
 
     map_cxxstd = lambda cxxstd: "2a" if cxxstd == "20" else cxxstd
-    cxxstds = ("17", "20")
+    cxxstds = ("17", "20", "23")
     variant(
         "cxxstd",
         default="17",
@@ -39,6 +39,7 @@ class PikaAlgorithms(CMakePackage):
 
     conflicts("%gcc@:8")
     conflicts("%clang@:8")
+    conflicts("cxxstd=23", when="^cmake@:3.20.2")
 
     # Other dependencies
     depends_on("boost@1.71:")
diff --git a/var/spack/repos/builtin/packages/pika/package.py b/var/spack/repos/builtin/packages/pika/package.py
index 7321aefc612..35a0436bcef 100644
--- a/var/spack/repos/builtin/packages/pika/package.py
+++ b/var/spack/repos/builtin/packages/pika/package.py
@@ -41,7 +41,7 @@ class Pika(CMakePackage, CudaPackage, ROCmPackage):
     generator("ninja")
 
     map_cxxstd = lambda cxxstd: "2a" if cxxstd == "20" else cxxstd
-    cxxstds = ("17", "20")
+    cxxstds = ("17", "20", "23")
     variant(
         "cxxstd",
         default="17",
@@ -88,6 +88,7 @@ class Pika(CMakePackage, CudaPackage, ROCmPackage):
     conflicts("%gcc@:8", when="@0.2:")
     conflicts("%clang@:8", when="@0.2:")
     conflicts("+stdexec", when="cxxstd=17")
+    conflicts("cxxstd=23", when="^cmake@:3.20.2")
 
     # Other dependencies
     depends_on("boost@1.71:")