Sunan an-Nasa'i 839
سنن النسائي#839SahihIt was narrated from that the Prophet (ﷺ) said:"Prayer in congregation is twenty-five levels better than a prayer offered on one's own
Scholarly Authentication
We show the most cautious grade (weakest-wins) as the overall label. Individual scholars graded it as follows:
Abu GhuddahSahih Isnaad
Al-AlbaniSahih Isnaad
Zubair Ali ZaiIsnaad Sahih
In-book reference: 10:63