Sahih Muslim , Book 32, Hadith 55 (In-Book) ⓘ

It has been narrated on the authority of Abu Huraira that the Messenger of Allah said: If you come to a township (which has surrendered without a formal war) and stay therein, you have a share (that will be in the form of an award) in (the properties obtained from) it. If a township disobeys Allah and His Messenger (and actually fights against the Muslims) one-fifth of the booty seized therefrom is for Allah and His Apostle and the rest is for you.

حَدَّثَنَا أَحْمَدُ بْنُ حَنْبَلٍ، وَمُحَمَّدُ بْنُ رَافِعٍ، قَالاَ حَدَّثَنَا عَبْدُ الرَّزَّاقِ، أَخْبَرَنَا مَعْمَرٌ، عَنْ هَمَّامِ بْنِ مُنَبِّهٍ، قَالَ هَذَا مَا حَدَّثَنَا أَبُو هُرَيْرَةَ، عَنْ رَسُولِ اللَّهِ صلى الله عليه وسلم فَذَكَرَ أَحَادِيثَ مِنْهَا وَقَالَ قَالَ رَسُولُ اللَّهِ صلى الله عليه وسلم ‏ "‏ أَيُّمَا قَرْيَةٍ أَتَيْتُمُوهَا وَأَقَمْتُمْ فِيهَا فَسَهْمُكُمْ فِيهَا وَأَيُّمَا قَرْيَةٍ عَصَتِ اللَّهَ وَرَسُولَهُ فَإِنَّ خُمُسَهَا لِلَّهِ وَلِرَسُولِهِ ثُمَّ هِيَ لَكُمْ ‏" ‏ ‏.‏