What is the ruling on swallowing saliva after it reaches the lips?
If saliva reaches the lips, then the person swallows it unintentionally, such as if he licks his lips and the like unintentionally, there is no blame on him. Similarly, if it dries up, then he closes his lips, its traces disappear when it dries up, and there is nothing left that could cause one to break the fast at all, whether deliberately or by mistake. If you deliberately swallow this saliva after it reaches the lips, then there is a difference of scholarly opinion as to whether that breaks the fast. For more details, please see the long answer.
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