diff --git a/internal/completion/objectstorage.go b/internal/completion/objectstorage.go
index ab52985b9..71ba98730 100644
--- a/internal/completion/objectstorage.go
+++ b/internal/completion/objectstorage.go
@@ -8,7 +8,7 @@ import (
 	"github.com/spf13/cobra"
 )
 
-// ObjectStorage implements argument completion for gateways, by uuid or name.
+// ObjectStorage implements argument completion for managed object storages, by uuid or name.
 type ObjectStorage struct{}
 
 // make sure ObjectStorage implements the interface
@@ -25,5 +25,5 @@ func (s ObjectStorage) CompleteArgument(ctx context.Context, svc service.AllServ
 		vals = append(vals, objsto.UUID, objsto.Name)
 	}
 
-	return MatchStringPrefix(vals, toComplete, true), cobra.ShellCompDirectiveNoFileComp
+	return MatchStringPrefix(vals, toComplete, false), cobra.ShellCompDirectiveNoFileComp
 }
diff --git a/internal/completion/objectstorage_test.go b/internal/completion/objectstorage_test.go
new file mode 100644
index 000000000..c7a71dc7b
--- /dev/null
+++ b/internal/completion/objectstorage_test.go
@@ -0,0 +1,35 @@
+package completion_test
+
+import (
+	"context"
+	"fmt"
+	"testing"
+
+	"github.com/UpCloudLtd/upcloud-cli/v3/internal/completion"
+	smock "github.com/UpCloudLtd/upcloud-cli/v3/internal/mock"
+	"github.com/UpCloudLtd/upcloud-go-api/v8/upcloud"
+	"github.com/spf13/cobra"
+	"github.com/stretchr/testify/assert"
+	"github.com/stretchr/testify/mock"
+)
+
+func TestObjectStorage_CompleteArgument(t *testing.T) {
+	mService := new(smock.Service)
+	mService.On("GetManagedObjectStorages", mock.Anything, mock.Anything).Return([]upcloud.ManagedObjectStorage{
+		{UUID: "objsto-uuid-1", Name: "MockBucket"},
+		{UUID: "objsto-uuid-2", Name: "another-bucket"},
+	}, nil)
+
+	vals, directive := completion.ObjectStorage{}.CompleteArgument(context.TODO(), mService, "MOCK")
+	assert.Equal(t, []string{"MockBucket"}, vals)
+	assert.Equal(t, cobra.ShellCompDirectiveNoFileComp, directive)
+}
+
+func TestObjectStorage_CompleteArgumentServiceFail(t *testing.T) {
+	mService := new(smock.Service)
+	mService.On("GetManagedObjectStorages", mock.Anything, mock.Anything).Return(nil, fmt.Errorf("MOCKFAIL"))
+
+	vals, directive := completion.ObjectStorage{}.CompleteArgument(context.TODO(), mService, "mock")
+	assert.Nil(t, vals)
+	assert.Equal(t, cobra.ShellCompDirectiveNoFileComp, directive)
+}