Gdansk - cash?

I didn't go to Gdansk, but in Warsaw, Wroclaw, and Krakow, credit card and tap phone to pay was widespread. Only a few (some of them ambitious) restaurants required cash. Railroad tickets were easily put on a credit card. However, EVERY credit card transaction presented a stealthy, disingenuous attempt to get you to consent to Dynamic Currency Conversion.

If you don't know what that is, find out. Because you need the confidence to make the choice between:
1-"Safe guaranteed currency transaction with us"
2-"Unknown exchange rate by [alleged] predatory credit card company"

Of course, you WANT to choose #2, otherwise known as (but not named as ... ) "Pay In Zloty, Local Currency." #1 costs 3% to 4% MORE!

Tap & pay. You might want to have a little PLN on hand. As above, you'll be given a choice for DCC or PLN; always choose to pay in the local currency.

I was in Gdansk in August and used cash only for tips (food tour guide, restaurants, hotel staff) and post cards. Everything else, including transit and the meal at restaurants was tap to pay with my phone.

I got 100 PLN (about $25) in cash at an ATM, which lasted my 6.5 days.

We spent about 10 days total in Poland last summer (mostly in Gdańsk and Kraków) and never withdrew a single złoty from an ATM. Credit cards or Google Wallet everywhere, for everything. Poland has a very modern commercial system, and cash use is similar to the UK: infrequent.

By the way, the World War II Museum in Gdańsk is unbelievable. A should-not-miss IMO. You'll love Poland.

Great, thank you everyone.

I was in Gdansk and Warsaw last May (Riga prior to that) and didn't have any cash for all locations other than some Euros for a flea market in Riga. Everywhere I went in Poland I simply used my card just as I do at home. Other than the flea market in Riga I haven't used cash anywhere in Europe for the last few years with the exception of a €1 coin for supermarket trolleys or coat lockers.