Hazrat Sobaan (RZ) has narrated the Holy Prophet (Peace Be Upon Him –
) as saying “Fasting of one month is equal to the fasting of ten months. Then this is equivalent to a year i.e. the month of Ramadan and after that (in Shawwal) fast of six days.
(Darmey Shareef page 274 No. 737 Tarteeb Shareef page 845)