Minehut
Minehut is, in my opinion, the best free hosting service out there for Minecraft servers. Their support members are top quality, they allow you to advertise for free, and you can get paid plans for free just by voting every day. I'm currently a moderator on their platforms, and they treat us with respect, and go out of their way to make sure that we have a great experience. The admins here are amazing and professional, and I couldn't ask for a better management team.