Is it haram to betray a trust?

Haram Money & business Quran · 2

Short answer

Yes. The Quran commands returning trusts to their owners (4:58) and forbids betraying them (8:27). This includes money left with you, secrets, and the duties of a job. Delaying payment of a debt when you are able to pay is also a form of injustice.

Evidence

Quran

۞ إِنَّ ٱللَّهَ يَأْمُرُكُمْ أَن تُؤَدُّوا۟ ٱلْأَمَٰنَٰتِ إِلَىٰٓ أَهْلِهَا وَإِذَا حَكَمْتُم بَيْنَ ٱلنَّاسِ أَن تَحْكُمُوا۟ بِٱلْعَدْلِ ۚ إِنَّ ٱللَّهَ نِعِمَّا يَعِظُكُم بِهِۦٓ ۗ إِنَّ ٱللَّهَ كَانَ سَمِيعًۢا بَصِيرًۭا ﴿٥٨﴾

Lo! Allah commandeth you that ye restore deposits to their owners, and, if ye judge between mankind, that ye judge justly. Lo! comely is this which Allah admonisheth you. Lo! Allah is ever Hearer, Seer.

يَٰٓأَيُّهَا ٱلَّذِينَ ءَامَنُوا۟ لَا تَخُونُوا۟ ٱللَّهَ وَٱلرَّسُولَ وَتَخُونُوٓا۟ أَمَٰنَٰتِكُمْ وَأَنتُمْ تَعْلَمُونَ ﴿٢٧﴾

O ye who believe! Betray not Allah and His messenger, nor knowingly betray your trusts.

This is general information, not a fatwa. For your own situation, ask a qualified scholar.