Abstract <p>With increasing pressures on freshwater resources worldwide, efforts are being made to identify new ways to meet water needs. Of the various ways of using water in a mosque, ablution (purification ritual) is generally considered the greatest. Being low in contamination as compared to other greywater sources, ablution greywater possesses a high potential for reuse. This review article is intended to gather different ablution water treatment options in one place and their removal efficiencies in terms of TSS, TDS, turbidity, fecal coliforms, total coliforms, and <i>E. coli</i>. After being treated, the water can also be reused for various purposes. Mosque cleaning, landscape irrigation, toilet flushing, mosque residential quarters, and ablution are some of the applications for which treated ablution water can be used. Despite many advantages of reusing ablution water, public acceptance and financial problems are some of the challenges that hinder the successful implementation of the reuse scheme. To overcome the obstacles, the government needs to financially support it through subsidies and rebates and promote public awareness regarding ablution greywater treatment and reuse.</p> Graphical Abstract <p></p>