how many cards in spades needed for valid cut

A valid cut in Spades only needs one spade card played on a trick when you are no longer able to follow the lead suit. That’s what “cutting” or “trumping” means: playing a spade to win the trick with a trump card.

How it works

• If you still have cards in the suit that was led, you usually must follow suit.
• If you do not have that suit, you may “cut” by playing any spade.
• The first spade played in a game is often called “breaking spades,” which allows spades to be led later.

Deal size in Spades

In the standard game, each player gets 13 cards from a 52-card deck. In cutthroat versions, the deal can vary, such as 17 cards each for 3 players or 10 cards each for 5 players.

TL;DR

For a valid cut , you only need one spade played when you can’t follow suit; there is no minimum number of spades in your hand beyond having at least one spade available.