diff --git a/pkgs/os-specific/linux/kernel/linux-rt-6.6.nix b/pkgs/os-specific/linux/kernel/linux-rt-6.6.nix
new file mode 100644
index 000000000000..b586dc392a6c
--- /dev/null
+++ b/pkgs/os-specific/linux/kernel/linux-rt-6.6.nix
@@ -0,0 +1,45 @@
+{ lib, buildLinux, fetchurl
+, kernelPatches ? [ ]
+, structuredExtraConfig ? {}
+, extraMeta ? {}
+, argsOverride ? {}
+, ... } @ args:
+
+let
+  version = "6.6.15-rt22"; # updated by ./update-rt.sh
+  branch = lib.versions.majorMinor version;
+  kversion = builtins.elemAt (lib.splitString "-" version) 0;
+in buildLinux (args // {
+  inherit version;
+
+  # modDirVersion needs a patch number, change X.Y-rtZ to X.Y.0-rtZ.
+  modDirVersion = if (builtins.match "[^.]*[.][^.]*-.*" version) == null then version
+    else lib.replaceStrings ["-"] [".0-"] version;
+
+  src = fetchurl {
+    url = "mirror://kernel/linux/kernel/v6.x/linux-${kversion}.tar.xz";
+    sha256 = "1ajzby6isqji1xlp660m4qj2i2xs003vsjp1jspziwl7hrzhqadb";
+  };
+
+  kernelPatches = let rt-patch = {
+    name = "rt";
+    patch = fetchurl {
+      url = "mirror://kernel/linux/kernel/projects/rt/${branch}/older/patch-${version}.patch.xz";
+      sha256 = "0dr4lb6f95vj8vzhlvy353dk6k694f1s6qfxr10m48hzyyqyaxdy";
+    };
+  }; in [ rt-patch ] ++ kernelPatches;
+
+  structuredExtraConfig = with lib.kernel; {
+    PREEMPT_RT = yes;
+    # Fix error: unused option: PREEMPT_RT.
+    EXPERT = yes; # PREEMPT_RT depends on it (in kernel/Kconfig.preempt)
+    # Fix error: option not set correctly: PREEMPT_VOLUNTARY (wanted 'y', got 'n').
+    PREEMPT_VOLUNTARY = lib.mkForce no; # PREEMPT_RT deselects it.
+    # Fix error: unused option: RT_GROUP_SCHED.
+    RT_GROUP_SCHED = lib.mkForce (option no); # Removed by sched-disable-rt-group-sched-on-rt.patch.
+  } // structuredExtraConfig;
+
+  extraMeta = extraMeta // {
+    inherit branch;
+  };
+} // argsOverride)
diff --git a/pkgs/top-level/linux-kernels.nix b/pkgs/top-level/linux-kernels.nix
index 62caa91bd496..31cce49051a9 100644
--- a/pkgs/top-level/linux-kernels.nix
+++ b/pkgs/top-level/linux-kernels.nix
@@ -185,6 +185,14 @@ in {
       ];
     };
 
+    linux_rt_6_6 = callPackage ../os-specific/linux/kernel/linux-rt-6.6.nix {
+      kernelPatches = [
+        kernelPatches.bridge_stp_helper
+        kernelPatches.request_key_helper
+        kernelPatches.export-rt-sched-migrate
+      ];
+    };
+
     linux_6_7 = callPackage ../os-specific/linux/kernel/mainline.nix {
       branch = "6.7";
       kernelPatches = [
@@ -613,6 +621,7 @@ in {
      linux_rt_5_10 = packagesFor kernels.linux_rt_5_10;
      linux_rt_5_15 = packagesFor kernels.linux_rt_5_15;
      linux_rt_6_1 = packagesFor kernels.linux_rt_6_1;
+     linux_rt_6_6 = packagesFor kernels.linux_rt_6_6;
      __attrsFailEvaluation = true;
   };
 
@@ -663,7 +672,7 @@ in {
     linux_latest = packages.linux_6_7;
     linux_mptcp = throw "'linux_mptcp' has been moved to https://github.com/teto/mptcp-flake";
     linux_rt_default = packages.linux_rt_5_4;
-    linux_rt_latest = packages.linux_rt_6_1;
+    linux_rt_latest = packages.linux_rt_6_6;
   } // { __attrsFailEvaluation = true; };
 
   manualConfig = callPackage ../os-specific/linux/kernel/manual-config.nix {};