Click on the person icon in the top right, log in, then click again and select Upgrade. Follow the steps to apply for upgrade credit.  If your play:5 is gen 1, it’s 30% credit towards one item, including sets.  A play:5 gen 2 is 15%, IIRC.  play:3 is 15%.  So you would get 30-15% off the set, with another 15% to purchase something else.

I believe it’s one voucher per item and that a ‘set’ counts as one item - so whatever discount voucher you have.

You can check the voucher availability in your online Sonos Account and even add the item to your shopping basket and see what discount you have available to apply, prior to purchase.

Note: the use of discount vouchers apparently are ’not in conjunction with any other offer’ that maybe available at the time (a product in a Sonos Sale for example) and is for new items only, not refurbished.

At least that’s my own understanding of how the vouchers can be used.

Love the “Set” discount option, traded one old Sonos for 30% off an Arc, Sub and two Ones.

Sure beat needing to use four discounts.

https://www.sonos.com/en-us/shop/surround-set-arc-sub-one-sl

Bridge, not sure it used to give you something towards a Boost but you’d need to contact Sonos to be sure what the current deal is. 

https://www.sonos.com/en-us/upgrade

https://www.sonos.com/en-us/legal/upgrade-terms