Expenditure in Poland - Forex Card doesn't have Złoty

Assuming that card works like a standard Visa/Mastercard, it will work fine. Whenever I have used my (GBP) Mastercard in Poland, the card machine has asked if I want to pay in Z?oty or convert to GBP (and siliar in other countries with other currencies)

Note that the conversion rate is usually much worse than the Visa/Mastercard rate, so it's generally better to pay in the local currency and let your card issuer do the conversion - but check their terms first to make sure they don't charge a commission.

It is not a bad option these days to use your regular debit card (at ATMs) or credit card. Check with your bank about the foreign currency charges. Indian banks generally give your a good currency conversion rate but they do charge 2-3.5% foreign currency fee plus 18% (of the fee) GST. In my experience, credit card fees tend to be higher. Call your bank and find out that day's Forex rate and the foreign currency fees applicable to your card(s).

I generally do try to get a Forex card and some cash as a fallback. Since you are not able to get zloty, carrying Euros/GBP as backup should be fine.

Hope you enjoy your trip!

POST SUCCESSFUL TRIP UPDATE: I had carried an HDFC Regalia Forex Plus card. You can load money in US Dollars to it and swipe it anywhere, in any currency. The conversion charges will only be applied when loading money, not while using it. ATM withdrawal costs $4 per transaction. My previous card (the one in my original question content) charged $2 per withdrawal but it would cost me double conversion charges. As I mentioned in the description, it had 23 currencies but it didn't support Zloty, so I would be charged twice, once for loading money, depending on the currency I load, and then for conversion from that currency to Zloty. It could be any other country who's currency is not supported by this card. The ATM withdrawal charges are irrespective of the amount you withdraw.

I had a successful trip, and didn't need to withdraw any cash, any time. My Forex contactless card was accepted everywhere. I mean literally everywhere, including the machines inside trams, trains, restaurants, even small stores. I haven't even seen the Polish currency! :) I used the same card in UK and Germany, and most of the times didn't need any cash. In my entire trip, I withdrew money only twice. Once in Derby to pay my Airbnb, and once in Itzehoe (Germany), to pay my taxi driver.

So anyone who stumbles across this post, don't worry about cash or not in Poland, UK or Germany. It's safe to withdraw a sufficient amount once and store it somewhere as a back up. Contactless works in most of the places.

Most businesses that take cards in Poland will allow you to pay in Euros. Withdrawing cash from ATM's is also possible with Euro cards. The conversion rate may or may not be the best, but you can do that.

Use card in ATM MACHINE to withdraw your cash in your location, or dispense your money with card in any super market which can accept your card or e-money