Abu Ayub reported,

The Messenger of Allah ﷺ said, "Whoever fasts Ramadan and follows it with six days of Shawwal, it is as if he has fasted the entire year."

Azami 4429

Sahih

عن أبي أيوب الأنصاري

أن رسول الله ﷺ قال: من صام رمضان وأتبعه ستا من شوال، كان كصيام الدهر.

الأعظمي 4429صحيح
Contents
Reference
Commentary
Ayat
Collection
Jami al-Kamil
Book
Fasting
Chapter
Voluntary fasting and encouragement to do it
Section
Virtue of fasting six days of Shawwal following Ramadan
Numbering
Jami al-Kamil 4429 (2nd edition)
Azami 4429