Waiting Period of the Lost Husband's Wife

A woman whose husband is missing and whose whereabouts is unknown to her must wait for four years and then observe the ‘Iddah (of a widow) for four months and ten days. After that, she is allowed to marry

‘Umar ibn al-Khattāb (may Allah be pleased with him) said: “A woman whose husband is missing and whose whereabouts is unknown to her must wait for four years and then observe the ‘Iddah (of a widow) for four months and ten days. After that, she is allowed to marry.”