Four.
Four. But they filled five.
Only four
Olympic Class Ocean liners can stay afloat with the first 3 or 6 separate compartmentsflooded but only to the top of the bulkhead.
Titanic's master builder, Thomas Andrews, had taken courses in naval architecture and ensured that Titanic could stay afloat with up to four compartments flooded.
wwell titanic had 16 water tight compartments if it cut 2 and 5 filled up it could stay afloat and be rescued and toed back to southhampton shipyard to be mended but the iceberg cut in 5 compartments so the titanic was doomed
4. When it struck the iceberg, 6 filled.
titanic sank because she hit the iceberg on her starboard side causing 5 compartments to flood. titanic could stay afloat with 4 compartments but not 5
RMS Titanic's first five compartments filled with water following a brush-by collision with an iceberg. The ship probably could have floated with as many as four compartments flooded, but with the loss of the fifth, the ship's head (or bow) was pulled down to a point where the rising water was able to spill over the tops of the following bulkheads one after the other, dooming the ship.
Five. It could stay afloat with the first four flooded, but the fifth one was her death sentence.
5 compartments were ruptered by the iceberg, which is one more that the Titanic could stand
An iceberg struck the starboard side of the Titanic on April 14th, around midnight. The iceberg flooded 5 watertight compartments, while she could only stay afloat with 4 flooded.
She had eight in all, and could have remained afloat with three of them flooded. But the gash punched in her side was 300ft long and opened up FIVE of them to the sea, meaning that her sinking was inevitable.