diff --git a/src/libstore/build/substitution-goal.cc b/src/libstore/build/substitution-goal.cc
index d16e530a4..ac18de304 100644
--- a/src/libstore/build/substitution-goal.cc
+++ b/src/libstore/build/substitution-goal.cc
@@ -268,16 +268,18 @@ Goal::Co PathSubstitutionGoal::tryToRun(
     try {
         promise.get_future().get();
     } catch (std::exception & e) {
-        printError(e.what());
-
         /* Cause the parent build to fail unless --fallback is given,
            or the substitute has disappeared. The latter case behaves
            the same as the substitute never having existed in the
            first place. */
         try {
             throw;
-        } catch (SubstituteGone &) {
+        } catch (SubstituteGone & sg) {
+            /* Missing NARs are expected when they've been garbage collected.
+               This is not a failure, so log as a warning instead of an error. */
+            logWarning({.msg = sg.info().msg});
         } catch (...) {
+            printError(e.what());
             substituterFailed = true;
         }
 
diff --git a/tests/functional/binary-cache.sh b/tests/functional/binary-cache.sh
index 2c102df07..d801ac6aa 100755
--- a/tests/functional/binary-cache.sh
+++ b/tests/functional/binary-cache.sh
@@ -111,7 +111,13 @@ clearStore
 
 mv "$cacheDir/nar" "$cacheDir/nar2"
 
-nix-build --substituters "file://$cacheDir" --no-require-sigs dependencies.nix -o "$TEST_ROOT/result"
+nix-build --substituters "file://$cacheDir" --no-require-sigs dependencies.nix -o "$TEST_ROOT/result" 2>&1 | tee "$TEST_ROOT/log"
+
+# Verify that missing NARs produce warnings, not errors
+# The build should succeed despite the warnings
+grepQuiet "does not exist in binary cache" "$TEST_ROOT/log"
+# Ensure the message is not at error level by checking that the command succeeded
+[ -e "$TEST_ROOT/result" ]
 
 mv "$cacheDir/nar2" "$cacheDir/nar"