Check out this thread:

This way: https://support.soundiiz.com/hc/en-us/articles/360018717099-Export-Sonos-playlists-and-transfer-them-with-Soundiiz

Yes, it is possible to copy a Sonos playlist to Spotify. Here are the steps you can follow:

1. Open the Sonos app on your device and select the playlist you want to copy.
2. Click on the three dots (...) icon next to the playlist name and select "Export Playlist."
3. Choose the location on your device where you want to save the exported playlist file.
4. Once the export is complete, open your Spotify account on a web browser or the desktop app.
5. Click on "File" and select "Import Playlists" from the drop-down menu.
6. Choose the exported Sonos playlist file from your device and click "Open."
7. The playlist will be imported into your Spotify account, and you can access it from the "Playlist" section of your Spotify app.

Additionally, if you are having trouble exporting or transferring your Sonos playlist to Spotify, you may want to consider using a third-party tool like Musconvtool. I hope this suggestion helps you to easily transfer your Sonos playlist to Spotify using Musconvtool.

I appreciate this is an old post but after spending about an hour yesterday searching for the same (including stumbling on this post which is why I’m adding this) I found SonoSaver.

Yes, it’s shareware but every other solution out there seemed like a workaround within an app that disguises itself as free yet requires you upgrade to the paid option to export your playlists anyway. Whereas SonoSaver was specifically built for saving the playlists. 

You have anything to do with this App you're promoting that has very limited functionality unless you pay for the full version?

As it happens, I recently found this post a few days back and tried it but the import into Soundiiz fails each time.

Hahaha, I approve of your cynicism! I would be the same. I have absolutely nothing to do with SonoSaver. For context, this is a rundown of my playlist export journey:

• Searched online for Sonos playlist export options. Full disclosure: my focus is mixed and mainly M3U playlists, not Spotify only.
• I found this very thread. Tried the above with MediaMonkey. Failed. It also asked for Plus membership for full access. Was I prepared to spend money for something that showed no evidence of working? No.
• Kept searching. Found a post on reddit by the SonoSaver developer where he said after being unable to find an app that exported playlists, he decided to build his own.
• I went to his website, had a read and decided I may as well try it.
• I downloaded SonoSaver, installed it, saw it was limited to 20 tracks unless you paid the €6 shareware license. I gave it a try. Within 4 clicks I had proof of concept playlists. Given I’d wasted a couple of hours searching for options, I was giddy with excitement.
• I went straight back to his website and sent him €10 because I was so happy to have found something that did what I wanted. It’s not bloated with other features. Its purpose is exporting playlists. And I was already prepared to spend around £10 for an app because rebuilding all my playlists would have been a crazy long task.
• Within 12 hours, he’d emailed me back with the unlock key. 4 clicks later, I had a folder packed with full playlists that I’d built up over the years. I am a happy customer.

My suggestions is download the free version and if it does what what you want, you’ve found your answer. If it doesn’t give you the type of playlists you’re after, then it’s not the one you’re looking for. What I like about SonoSaver is he’s not pretending there are additional features behind a paywall. If you get a 20-song playlist out of it, you’ll be able to get a 500+ playlist out of it too.

So why my original post? At the end of the email with the unlock key, the developer asked “In case you found out about it by a forum, it would be great if you could post some positive comment about SonoSaver. Unfortunately, people hardly find out about my app. Your help is highly appreciated!”

So I did!

Even as I wrote my first post I knew it would come across as fake promotion as it was my first and only post. But I assure you I lack the basic skills to create an functioning application. 

You can  easily copy Sonos playlist to Spotify by using our musconv tool.

Hi all,

Using this and other threads I successfully transferred 2 large Sonos playlists to Spotify. I’m sure there are easier ways to do this, but I just wanted to share what I did, and hopefully that could help someone else

1. Buy SonoSaver thru Microsoft Store (costs like $5)
2. In SonoSaver I selected option 3 Export to Files, marked my 2 Sonos playlists and exported (all default values)
3. I signed up for a 1 month subscription of Musconv.com and installed
4. I imported the csv files to Excel, opened another Excel and imported the template for musconv (from here www.musconv.com/playlists/playlist.csv)
5. I adjusted my exportfiles to contain only the columns and content that the examplefile showed
6. In MusConv i selected CSV as source, imported my playlists, selected Spotify as destination (logged on) and adjusted a few songs where there was no match (due to swedish characters), removed a few duplicates and started the transfer.

I must say that MusConv was a great piece of software, and I’ll definitly look into this more in the future, but for now I cancelled my subscription.

Hope this helps someone