Currently you can use Spotify Free on Amazon Fire stick or Google Home but on Amazon Echo you are able to only use it with Premium.
Please, allow it on Amazon Echo, i dont bother about ads and I really want to use Spotify Free with my Echo device
Updated on 2019-12-04
We are pleased to confirm that this has now launched in the U.S., Australia and New Zealand. You'll find more info on this here.
If we have any info on this for other markets in the future, we'll come back with an update.