diff --git a/nixos/modules/config/swap.nix b/nixos/modules/config/swap.nix
index d0fc0d4a3ea..adb4e229421 100644
--- a/nixos/modules/config/swap.nix
+++ b/nixos/modules/config/swap.nix
@@ -185,6 +185,8 @@ in
           { description = "Initialisation of swap device ${sw.device}";
             wantedBy = [ "${realDevice'}.swap" ];
             before = [ "${realDevice'}.swap" ];
+            # If swap is encrypted, depending on rngd resolves a possible entropy starvation during boot
+            after = mkIf (config.security.rngd.enable && sw.randomEncryption.enable) [ "rngd.service" ];
             path = [ pkgs.utillinux ] ++ optional sw.randomEncryption.enable pkgs.cryptsetup;
 
             script =
diff --git a/nixos/modules/security/rngd.nix b/nixos/modules/security/rngd.nix
index d9d6d9c9f25..5566c53897d 100644
--- a/nixos/modules/security/rngd.nix
+++ b/nixos/modules/security/rngd.nix
@@ -39,12 +39,15 @@ in
 
       description = "Hardware RNG Entropy Gatherer Daemon";
 
+      # rngd may have to start early to avoid entropy starvation during boot with encrypted swap
+      unitConfig.DefaultDependencies = false;
       serviceConfig = {
         ExecStart = "${pkgs.rng-tools}/sbin/rngd -f"
           + optionalString cfg.debug " -d";
+        # PrivateTmp would introduce a circular dependency if /tmp is on tmpfs and swap is encrypted,
+        # thus depending on rngd before swap, while swap depends on rngd to avoid entropy starvation.
         NoNewPrivileges = true;
         PrivateNetwork = true;
-        PrivateTmp = true;
         ProtectSystem = "full";
         ProtectHome = true;
       };