Hadith 19
أَخْبَرَنَا إِسْحَاقُ بْنُ إِبْرَاهِيمَ، قَالَ أَنْبَأَنَا إِسْمَاعِيلُ، عَنْ عَبْدِ الْعَزِيزِ بْنِ صُهَيْبٍ، عَنْ أَنَسِ بْنِ مَالِكٍ، قَالَ كَانَ رَسُولُ اللَّهِ صلى الله عليه وسلم إِذَا دَخَلَ الْخَلاَءَ قَالَ " اللَّهُمَّ إِنِّي أَعُوذُ بِكَ مِنَ الْخُبُثِ وَالْخَبَائِثِ " .
It was narrated that Anas bin Malik said:
"The Messenger of Allah (ﷺ) entered Al-Khala' (the toilet) and said: 'Allahumma inni a'uthu bika min al-khubuthi wal-khaba'ith (O Allah, I seek refuge with You from male and female devils)."[1] [1] See Ma'alam As-Sunan by Al-Khattabi. And Al-Khala' is the area one relieves oneself in. It refers to outside or other than that, it should not be understood to mean toilet only.
Reference : Sunan an-Nasa'i 19
In-book reference : Book 1, Hadith 19