Conditions for NS plans are on ns.nl, I suspect they will be on their website for a GVB plan too. Unfortunately you will indeed have to do some calculations with them. NS has a tool for it but besides being somewhat limited that only includes NS plans and thus can't help you completely here.

On a side note: make sure to have NS remove the part of their flex subscription for bus, tram and metro from your card if you haven't yet. Otherwise your GVB subscription on the same card will be ignored and you will pay too much for your travel with GVB.

Thank you very much! How do I make sure the side note you wrote?

Hi YuliHZ and welcome to the NS Community.

You can contact my colleagues of the NS Customer service to have your BTM product removed. BTM stands for bus, tram and metro. Once this is done, you'll start travelling on balance again in buses, trams and metros. However, a subscription of another public transport company, such as GVB, can then be placed on the same OV-chipcard as where your NS Flex is on.

Thanks! is their an email I can contact customer service? thanks!

I'm afraid not, you can contact us by phone, Chat, Facebook or X (Twitter).
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