According to Wikipedia:
5222 TCP XMPP client connection (RFC 6120) Official 5223 TCP XMPP client connection over SSL Unofficial 5269 TCP XMPP server connection (RFC 6120) Official 5298 TCP UDP XMPP JEP-0174: Link-Local Messaging / Official XEP-0174: Serverless Messaging 8010 TCP XMPP File transfers Unofficial
The port numbers are defined in RFC 6120 ยง 14.7.