German submarine U-1232 was a Type IX U-boat of Nazi Germany's Kriegsmarine during World War II.
German Type IXC/40 submarines were slightly larger than the original Type IXCs. U-1232 had a displacement of when at the surface and while submerged. The U-boat had a total length of , a pressure hull length of , a beam of , a height of , and a draught of . The submarine was powered by two MAN M 9 V 40/46 supercharged four-stroke, nine-cylinder diesel engines producing a total of for use while surfaced, two Siemens-Schuckert 2 GU 345/34 double-acting electric motors producing a total of for use while submerged. She had two shafts and two propellers. The boat was capable of operating at depths of up to .
The submarine had a maximum surface speed of and a maximum submerged speed of . When submerged, the boat could operate for at ; when surfaced, she could travel at . U-1232 was fitted with six torpedo tubes (four fitted at the bow and two at the stern), 22 torpedoes, one SK C/32 naval gun, 180 rounds, and a Flak M42 as well as two twin C/30 anti-aircraft guns. The boat had a complement of forty-eight.
She made one offensive patrol, from November 1944 until February 1945, to North America. On 14 January 1945, the boat torpedoed and sank three ships within 13 minutes near Halifax Harbour off the Atlantic coast of Canada. During this action she was damaged so severely that she was forced to return to base.
In May 1945 the British military captured U-1232 at Wesermünde, Germany. On 4 March 1946 the boat sank at after she foundered whilst being towed to the scuttling grounds.