Is zakat due on the deferred mahr?

The deferred dowry (Mahr Mu'akhkhar) is a debt owed by the husband, and its zakat depends on two situations:

1. If it is possible to demand it and the husband is wealthy and does not object: Zakat is due on it every year, because it is like complete ownership in her hand. 2. If the husband is poor, or it cannot be demanded for fear of angering the husband, or if custom dictates that it is not due except upon separation (divorce or death): No zakat is due on it unless it is received. When it is received, she pays zakat for one year, even if many years have passed.

Shaykh al-Islam Ibn Taymiyyah was asked about this and replied that the more plausible opinion is not to obligate zakat on it until a year has passed after its receipt, or to obligate a single zakat upon receipt. Both opinions have been stated within the Hanbali madhhab.