Chessy
Rook vs Bishop
Rook versus a lone bishop, with no pawns on the board, is a draw when the side with the bishop defends accurately — a full rook's worth of extra material still isn't enough to force a win here.
Learning to hold — or break — this fortress matters in real games. Study the position and test your understanding with Chessy.
Play free against the Chessy engine →Why the extra exchange isn't enough
A rook is worth more than a bishop, but a lone bishop plus king is a surprisingly resilient defensive unit. The defending king simply heads for a corner that matches its bishop's own color and shelters there; the bishop covers the checks a rook can throw at the king, and there's no way for the attacker to dislodge that shelter without stalemating or losing material back.
The defensive fortress
The key defensive idea is to keep the king near the corner square that matches the bishop's color (for a light-squared bishop, that's a light corner) and use the bishop to block checks along the diagonal leading into that corner. As long as the king and bishop cooperate, the rook can shuffle around and win nothing — this is why moves like Ra4 followed by centralizing with Kd2 make no real progress against solid defense.
When the defender can still go wrong
The danger for the defending side is getting the king trapped in the wrong-colored corner, or letting the bishop get pinned or driven away from the king entirely — in those specific situations the rook can sometimes force a win. Correct defense means the king actively seeks its own-color corner the moment the rook endgame arises, rather than drifting toward the center or the wrong side of the board.
Frequently asked questions
Is rook vs bishop always a draw?
With no pawns and accurate defense, yes. The defending king simply reaches the corner matching its bishop's color, where the bishop can block checks and the rook can't make progress.
How does the bishop side hold the draw?
By keeping the king near a corner of the same color as its bishop and using the bishop to interfere with checks along that diagonal, denying the rook any way to force the king out.
Can the rook ever win this endgame?
Only if the defending king is caught away from its own-color corner or the bishop gets separated from the king — with correct play from the start, the defender should never allow this.
Why is a bishop harder to beat here than expected?
A bishop, unlike a knight, can control long diagonals and interfere with checks from a distance, which is exactly what's needed to build a fortress in the right corner.