23 May 1940
For the second day in a row, the outbound boat encountered an enemy submarine in the North Sea. This time a torpedo track was seen passing the bow at a distance of about 50 metres.

29 May 1940
16.30 hours, Celtic Sea, southwest of Lands End: an unidentified aircraft dropped 2 depth charges, causing minor damage. (Sources: Ritschel)

31 May 1940
After a successful attack on convoy HGF-31 in the English Channel west of Guernsey, the boat was attacked for 4 hours with 34 depth charges. On going to periscope depth at 22.00 hours, an armed trawler attacked again, dropping 7 depth charges which caused moderate damage. (Sources: Ritschel)

4 Jun 1940
20.14 hours, south of Lands End: an unidentified aircraft dropped one bomb. No damage. (Sources: Ritschel)

23 Jun 1940
04.08 hours, off the Shetland Isles: an unidentified aircraft dropped 3 bombs on the inbound boat, damaging the periscope. (Sources: Ritschel)

3 Sep 1940
While searching for a convoy west of Ireland, an escort launched a series of depth charges over 5 runs, causing moderate damage and flooding that the crew were able to control. (Sources: Ritschel)

19 Oct 1940
Despite being shelled by an armed freighter, U-101 completed the launch of torpedoes in a final attack on convoy SC-7 north of Ireland. The shells missed, landing astern as U-101 was turning away and zig-zagging. (Sources: Ritschel)

29 Jan 1941
04.16 hours, North Atlantic west of Ireland: gunfire from a destroyer forced U-101 to dive as she was attempting to attack convoy SC-19. The 3 depth charges subsequently launched caused no damage. (Sources: Ritschel)

23 Apr 1941
The boat encountered a British submarine in the North Atlantic, which fired two torpedoes, but both missed.

24 Aug 1941
09.53 hours, near Rockall: an unidentified aircraft dropped 2 depth charges. No damage from this attack, but U-101 was subsequently forced to dive to evade aircraft operating in the area on five other occasions over the 24th-25th of August. (Sources: Ritschel)

28 Aug 1941
03.03 hours, Atlantic, west of Ireland: the boat was forced to dive by a destroyer while operating against convoy OS-4, and was attacked for 3 hours by several escorts with 30 depth charges. The attacks were accurate, but the only serious damage was a disabled periscope. (Sources: Ritschel)

13 Oct 1941
10.45 hours, Bay of Biscay: the outbound boat was attacked by a twin-engined aircraft which dropped 3 depth charges, causing minor damage. The attack also apparently caused an oil leak, because three more depth charges were dropped on the submerged boat at 16.42 hours. (Sources: Ritschel)

12 recorded attacks on this boat.