Reference: http://mufti.af.org.sa/ar/content/الكذب-من-غير-قصد-هل-هو-حرام؟
Question: Is lying without intending [to lie] prohibited?
Response: The basic rule with regard to lying is that it is not permitted, and it is a trait of the hypocrites. [But] there are certain circumstances where it is permissible to lie – as legislated in the hadeeth[1] – and they are three:
1) A husband [lying] to his wife, and the wife [lying] to her husband;
2) Reconciling between the [quarrelling] people;
3) In war – with the enemies.
Other than that, the basic rule with regard to lying is that it is not permitted.
Footnote:
[1] Asmaa. bint Yazeed said: “The Messenger of Allaah ﷺ said:
«Lying is not permitted except in three cases: [when] a man speaks to his wife to make her happy; lying at times of war; and lying in order to reconcile between people.»’ – transmitted by Muslim, no.4717, and at-Tirmidhee, no.1862 – who said it is a hasan hadeeth.
