|When you play this, it’s worthper Treasure card you have in play (counting this).|
Bank is a Treasure card from Prosperity. It gives a variable amount of , depending on how many other Treasures you've played before it. It counts Treasures that don't themselves give , like Potion or Horn of Plenty. It works best with large hands; in 5-card hands and without +Buy, it's rarely better than a Gold.
 Official FAQ
- When you play Bank, it is worth per Treasure you have in play, counting itself.
- If you play two copies of Bank in a row, the second one will be worth more than the first one.
- Playing more Treasures after Bank will not change how much you got from it.
 Other Rules clarifications
- Example Turn: You play 2 Coppers followed by a Venture. The Venture finds and Plays a Bank which will be worth . You play another Venture which finds another Bank, which is worth giving you a total of to spend.
 Strategy Article
Original article on the forums by Davio, with comments by others.
Bank is a lovely card, but it can also be a trap for many new players. While it's true that in practice it's often better than Gold in that it needs only 2 other Treasures to give you the same , it's also a bit random. If you ever end up drawing your Bank dead it gives you just where Gold would still have given . But a hand with just 1 Treasure is often a dead hand anyway so the Bank vs. Gold wouldn't have that much of a difference.
The thing with Bank is that it's often overkill on its own, it needs its biggest friend: +Buy. If you have a hand with 5 Banks you have 1+2+3+4+5 = Colony or Province. And remember that Bank only gives you more than Gold if it's the 4th or higher Treasure played. This means Bank needs hands with lots of Treasures.yet you can still only buy 1
 So what cards can Bank look to as a partner in crime?
Wharf is awesome and Council Room and Margrave are quite good as they give you not only the needed +Buy, but also a good draw. Drawing cards equals more Treasure cards equals higher worth Banks. Wharf is the best there is. Council Room gives you 4 cards and your opponent 1, while Margrave gives you 1 less card, but your opponent has to drop 2 cards. All in all Margrave may be slightly better because of the attack.
Using rspeer's Dominiate simulator (Geronimoo's doesn't work on my PC with Java 7), it seems Margrave wins about 60% vs. Council Room if we let the sim just buy that card on every. Wharf beats both, it beats Council Room with about 65% and Margrave with about 60%.
Other terminal drawers can be good, but then you have to get the +Buy from somewhere else.
You could use cantrips for your +Buy like Market and Worker's Village coupled with non-terminal drawers like Laboratory and Stables. Coupling a +Buy with other terminal drawers is risky business and you need quite a bit of luck to really be able to make use of it.
Tactician also works extremely well, as it both gives huge hands and gives +Buy.
It potentiates the effects of multiple Storytellers since money cards expended by Storytellers still count towards the total "in-game" money card tally for Bank.
 Trash for Benefit and Cost Advantages
Bank is a trash-for-benefit cards get a little extra out of it over Gold.card. That means most
- You can Upgrade Bank into a Province or Remake two Banks into two Provinces! Or Develop it into a Province and a Gold.
- You can Remodel (or Expand/Farmland) it into a Platinum or Apprentice it for 7 cards.
- Salvager it and you get + .
- When it gets Saboteured you could grab a Duchy and when it gets Swindled there are often no other cards around so you get it back.
- Bank is even funnier with Governor, because you could grab a Province on your opponent's turn.
- And to boot it even can't be Smuggled!
- With Haggler you could buy Bank and a card like Goons or Grand Market.
- It can't be stolen with Noble Brigand since that chooses only Silver or Gold.
 When Not to Choose Bank over Gold
If your hands are going to be cluttered with terminals and you will hardly ever reach the "4th Treasure" mark, stick with Gold. This can happen very easily. If every hand has exactly one terminal (like Big Money-Monument), your other cards need to be Treasures for Bank to make it worth your while over Gold and even then it's hardly more effective than Gold.
For example: A hand of Monument () + 3x Copper can buy a Province with both a Gold ( ) and a Bank ( ), so there's really no difference here. Often you will see a hand of Monument + 2x Copper and in this case both Gold and Bank get you to so again there's no real difference.
Using Bank instead of Gold in decks without +Buy is an effort in futility.
 When Not to Choose Bank
This is pretty easy: Engines that depend on action cards for their money have no business with Bank as they have no business with Treasure cards in general. A long King's Court-Grand Market chain doesn't want it and double Tactician decks also don't need it. Just like any Treasure can throw a wrench in money from actions based engines, so can Bank.
And obviously your classic rushes don't need Bank and you'll probably never even be able to afford it anyway.
- +Buy terminal drawers
- Engines with +Buy but without Copper-trashing, especially Wharf or Apothecary engines
- Trash for benefit
- Big Money (no advantage over Gold)
- Rush strategies
- Engines which rely on Actions for coin
- Lack of +Buy
- Attacks, especially cursers.
- Spoils and Counterfeit both take Treasures out of play before Bank can count them.
 English versions
|When you play this, it’s worthper Treasure card you have in play (counting this).||Digital version mistakenly putsymbols on the top banner instead of symbols.||Prosperity 1st Edition||October 2010|
|When you play this, it’s worthper Treasure card you have in play (counting this).||Prosperity 2nd Edition||February 2017|
 Other language versions
 Secret History. I wanted something else really simple and classic-seeming. It had been a good fit for Alchemy, since it counts Potions even if you don't end up spending them. Alchemy was years off though, years I say, and Prosperity needed a card now. Then when Alchemy got bumped up, I didn't steal this card back, because it required a little more of the Prosperity rules than I was comfortable with putting out ahead of Prosperity.