Chess Openings Lab
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Nimzo-Indian Defense: St. Petersburg Variation

The St. Petersburg Variation of the Nimzo-Indian is 4.e3 b6, where Black prepares ...Bb7 or ...Ba6 to fight for the light squares. White chooses Ne2, Bd3 or Be2, and Black aims to control e4 and pressure the c4 pawn.

Moves
1.d4 Nf6 2.c4 e6 3.Nc3 Bb4 4.e3 b6
ECO
E43, E44
Engine
+0.30 · a slight edge for White (Stockfish 17.1, depth 20)
Played
375 games in our lichess sample
White scores
50.0%

Key ideas for both sides

White

  • Play 5.Ne2, the engine's top choice, so a trade on c3 can be met by a knight recapture.
  • After Ne2, play a3 to force ...Bxc3+ and recapture with the e2 knight, keeping the pawns intact.
  • With 5.Bd3 and Nf3, castle and aim for e4, backed by the d3 bishop.
  • Consider Na4 against a bishop on b4, as in the second engine line, to dodge the trade.

Black

  • Develop with ...Bb7 to control e4 and support a later knight jump to e4.
  • Look at ...Ba6 against Ne2 or Bd3 to hit the c4 pawn and the f1 bishop.
  • Strike with ...c5 and ...d5 once White's pieces are committed and the king is castled.
  • Trade with ...Bxc3+ when it damages White's structure, and keep the bishop if White can recapture with a piece.

Plans and pawn structure

Black's ...b6 aims at the light squares, especially e4. The b7 bishop and the f6 knight control e4, and ...Ne4 can become a strong outpost. White wants to keep the pawns healthy with Ne2 and later a3, or develop with Bd3 and Nf3 and push e4. After ...c5 and ...d5, the center opens and the c4 pawn becomes a target. If White wins the bishop pair, a later f3 and e4 can break through.

What the engine plays from here

Stockfish 17.1 at depth 20 rates the position +0.30: a slight edge for White. Its three top choices for White:

  1. +0.30 5.Ne2 Bb7 6.a3 Bxc3+ 7.Nxc3 d5
  2. +0.25 5.Bd3 Bb7 6.Nf3 O-O 7.O-O c5
  3. +0.13 5.Be2 Bb7 6.Nf3 Bxc3+ 7.bxc3 O-O

Pawns, from White's side.

How it scores on lichess

375 rated lichess games reached this position; White scored 50.0%.

1200–159936.3%
1600–199944.9%
2000 and up58.3%

Light: White wins. Grey: draws. Dark: Black wins. About the sample.

Where it goes next

  • St. Petersburg Variation, Romanishin-Psakhis Variation5.Ne2 · rare
  • Normal Variation, Schlechter Defense5.Bd3 · rare

How to play against it

White, play 5.Ne2 and a3 to win the bishop pair without doubled pawns. With 5.Bd3, castle and prepare e4 while watching ...Ba6. Avoid slow moves; Black wants time for ...Bb7, ...Ne4 and ...f5 to grab the e4 square. If Black trades on c3, recapture with the knight.

Other lines with this name

The lichess opening list also files these lines under the same name, though they reach a different position: 1.d4 Nf6 2.c4 e6 3.Nc3 Bb4 4.e3 b6 5.Bd3 Bb7 6.Nf3; 1.d4 Nf6 2.c4 e6 3.Nc3 Bb4 4.e3 b6 5.Bd3 Bb7 6.Nf3 O-O; 1.d4 Nf6 2.c4 e6 3.Nc3 Bb4 4.e3 b6 5.Bd3 Bb7 6.Nf3 O-O 7.O-O.

Questions

What are the moves of the Nimzo-Indian Defense: St. Petersburg Variation?

The Nimzo-Indian Defense: St. Petersburg Variation starts 1.d4 Nf6 2.c4 e6 3.Nc3 Bb4 4.e3 b6. Its ECO code is E43, E44.

Is the Nimzo-Indian Defense: St. Petersburg Variation good for Black?

Stockfish 17.1 rates the position +0.30 at depth 20, which is a slight edge for White. In 375 lichess games from our sample, White scored 50.0%. A good practical choice for Black players who like quiet light-square play, and White needs a plan to fight for e4.

What is the main idea of the Nimzo-Indian Defense: St. Petersburg Variation?

Black plays ...b6 and ...Bb7 to control the e4 square and pressure c4. White chooses between Ne2 and Bd3, often trying to keep a healthy pawn structure.

What should White play next?

The engine's first choice is Ne2, with Bd3 and Be2 close behind. 5.Ne2 lets White recapture on c3 with a knight and keeps the pawns intact.

Updated October 2026. Sources and method.