ENOfficial
Abu Mas'ud reported God’s messenger as saying, “When someone spends on his family seeking his reward for it from God, it counts to him as sadaqa.” (Bukhari and Muslim.)
Source: sunnah.com
Other translations
Arabic
وَعَنْ أَبِي مَسْعُودٍ قَالَ: قَالَ رَسُولُ اللَّهِ صَلَّى اللَّهُ عَلَيْهِ وَسلم: «إِذا أَنْفَقَ الْمُسْلِمُ نَفَقَةً عَلَى أَهْلِهِ وَهُوَ يَحْتَسِبُهَا كَانَت لَهُ صَدَقَة»
sunnah.com