Personal
You may be looking for a non-profit hosting provider with a sustainable economic model, that has more chances of being up and running 20 years from now. Or you rather need a server that offers anonymous access via the Tor network? Here are some recommended options:
Chalec
Chalec.org is a non-commercial provider from France. You can sign up for their service directly from within your app.
XMPP.social
XMPP.social is one of several domains you can register for free with Hookipa.net. Their servers are located in Germany.
Disroot
Disroot is a non-commercial project based in the Netherlands and founded in 2015. It is run by a group of volunteers and offers various online services. You can learn more about them on their website here.
XMPP.is
XMPP.is is a privacy focused provider with servers located in Iceland. They offer sign ups and direct access via the Tor network.
Queer Spark
Queer Spark Queer Spark is a site dedicated to helping people of all walks of life connect with each other and build communities without the abuse that results from profit driven services and technologies.
Note that it is a constant work-in-progress and not the most reliable option if someone is looking for a server for something mission critical.
Others?
This is obviously not an exhaustive list and if you have a really good recommendation please contact us here: chat@joinjabber.org (web chat) (xmpp)
If you are the server operator of one of these services and disagree with being listed here, please contact us: servers@joinjabber.org (web chat) (xmpp) .