diff --git a/home-manager/default.nix b/home-manager/default.nix
index 1c5ab5d81..47281bc64 100644
--- a/home-manager/default.nix
+++ b/home-manager/default.nix
@@ -16,7 +16,6 @@ let
 
 in runCommand "home-manager" {
   preferLocalBuild = true;
-  allowSubstitutes = false;
   meta = with lib; {
     description = "A user environment configurator";
     maintainers = [ maintainers.rycee ];
diff --git a/home-manager/install.nix b/home-manager/install.nix
index e707c5733..3cefc7876 100644
--- a/home-manager/install.nix
+++ b/home-manager/install.nix
@@ -3,7 +3,6 @@
 runCommand "home-manager-install" {
   propagatedBuildInputs = [ home-manager ];
   preferLocalBuild = true;
-  allowSubstitutes = false;
   shellHookOnly = true;
   shellHook = ''
     confFile="''${XDG_CONFIG_HOME:-$HOME/.config}/nixpkgs/home.nix"
diff --git a/modules/home-environment.nix b/modules/home-environment.nix
index 5305a1bf6..4d4c5a72f 100644
--- a/modules/home-environment.nix
+++ b/modules/home-environment.nix
@@ -652,7 +652,6 @@ in
           "home-manager-generation"
           {
             preferLocalBuild = true;
-            allowSubstitutes = false;
           }
           ''
             mkdir -p $out
diff --git a/modules/programs/fish.nix b/modules/programs/fish.nix
index 0387df799..e39a141ce 100644
--- a/modules/programs/fish.nix
+++ b/modules/programs/fish.nix
@@ -310,7 +310,6 @@ in {
             nativeBuildInputs = [ pkgs.python2 ];
             buildInputs = [ cfg.package ];
             preferLocalBuild = true;
-            allowSubstitutes = false;
           } ''
             mkdir -p $out
             if [ -d $src/share/man ]; then
diff --git a/tests/modules/programs/firefox/profile-settings.nix b/tests/modules/programs/firefox/profile-settings.nix
index 605ff6692..fde4be563 100644
--- a/tests/modules/programs/firefox/profile-settings.nix
+++ b/tests/modules/programs/firefox/profile-settings.nix
@@ -32,7 +32,6 @@ with lib;
         firefox-unwrapped = pkgs.runCommand "firefox-0" {
           meta.description = "I pretend to be Firefox";
           preferLocalBuild = true;
-          allowSubstitutes = false;
           passthru.gtk3 = null;
         } ''
           mkdir -p "$out/bin"
diff --git a/tests/modules/programs/firefox/state-version-19_09.nix b/tests/modules/programs/firefox/state-version-19_09.nix
index 82fa039ca..7f3387e19 100644
--- a/tests/modules/programs/firefox/state-version-19_09.nix
+++ b/tests/modules/programs/firefox/state-version-19_09.nix
@@ -13,7 +13,6 @@ with lib;
         firefox-unwrapped = pkgs.runCommand "firefox-0" {
           meta.description = "I pretend to be Firefox";
           preferLocalBuild = true;
-          allowSubstitutes = false;
           passthru.gtk3 = null;
         } ''
           mkdir -p "$out/bin"