diff --git a/src/libfetchers/registry.cc b/src/libfetchers/registry.cc
index 81b2227de..74376adc0 100644
--- a/src/libfetchers/registry.cc
+++ b/src/libfetchers/registry.cc
@@ -114,7 +114,7 @@ static std::shared_ptr<Registry> getSystemRegistry()
 
 Path getUserRegistryPath()
 {
-    return getHome() + "/.config/nix/registry.json";
+    return getConfigDir() + "/nix/registry.json";
 }
 
 std::shared_ptr<Registry> getUserRegistry()
diff --git a/tests/config.sh b/tests/config.sh
index eaa46c395..01c78f2c3 100644
--- a/tests/config.sh
+++ b/tests/config.sh
@@ -1,15 +1,41 @@
 source common.sh
 
+# Isolate the home for this test.
+# Other tests (e.g. flake registry tests) could be writing to $HOME in parallel.
+export HOME=$TEST_ROOT/userhome
+
+# Test that using XDG_CONFIG_HOME works
+# Assert the config folder didn't exist initially.
+[ ! -e "$HOME/.config" ]
+# Without XDG_CONFIG_HOME, creates $HOME/.config
+unset XDG_CONFIG_HOME
+# Run against the nix registry to create the config dir
+# (Tip: this relies on removing non-existent entries being a no-op!)
+nix registry remove userhome-without-xdg
+# Verifies it created it
+[ -e "$HOME/.config" ]
+# Remove the directory it created
+rm -rf "$HOME/.config"
+# Run the same test, but with XDG_CONFIG_HOME
+export XDG_CONFIG_HOME=$TEST_ROOT/confighome
+# Assert the XDG_CONFIG_HOME/nix path does not exist yet.
+[ ! -e "$TEST_ROOT/confighome/nix" ]
+nix registry remove userhome-with-xdg
+# Verifies the confighome path has been created
+[ -e "$TEST_ROOT/confighome/nix" ]
+# Assert the .config folder hasn't been created.
+[ ! -e "$HOME/.config" ]
+
 # Test that files are loaded from XDG by default
-export XDG_CONFIG_HOME=/tmp/home
-export XDG_CONFIG_DIRS=/tmp/dir1:/tmp/dir2
+export XDG_CONFIG_HOME=$TEST_ROOT/confighome
+export XDG_CONFIG_DIRS=$TEST_ROOT/dir1:$TEST_ROOT/dir2
 files=$(nix-build --verbose --version | grep "User config" | cut -d ':' -f2- | xargs)
-[[ $files == "/tmp/home/nix/nix.conf:/tmp/dir1/nix/nix.conf:/tmp/dir2/nix/nix.conf" ]]
+[[ $files == "$TEST_ROOT/confighome/nix/nix.conf:$TEST_ROOT/dir1/nix/nix.conf:$TEST_ROOT/dir2/nix/nix.conf" ]]
 
 # Test that setting NIX_USER_CONF_FILES overrides all the default user config files
-export NIX_USER_CONF_FILES=/tmp/file1.conf:/tmp/file2.conf
+export NIX_USER_CONF_FILES=$TEST_ROOT/file1.conf:$TEST_ROOT/file2.conf
 files=$(nix-build --verbose --version | grep "User config" | cut -d ':' -f2- | xargs)
-[[ $files == "/tmp/file1.conf:/tmp/file2.conf" ]]
+[[ $files == "$TEST_ROOT/file1.conf:$TEST_ROOT/file2.conf" ]]
 
 # Test that it's possible to load the config from a custom location
 here=$(readlink -f "$(dirname "${BASH_SOURCE[0]}")")
@@ -24,4 +50,4 @@ exp_cores=$(nix show-config | grep '^cores' | cut -d '=' -f 2 | xargs)
 exp_features=$(nix show-config | grep '^experimental-features' | cut -d '=' -f 2 | xargs)
 [[ $prev != $exp_cores ]]
 [[ $exp_cores == "4242" ]]
-[[ $exp_features == "nix-command flakes" ]]
\ No newline at end of file
+[[ $exp_features == "nix-command flakes" ]]