21 May 1941
The boat was forced to dive by gunfire from HMS Verbena behind convoy HX-126 and in the next 4 hours heavily attacked with about 125 depth charges by her and HMS Burnham until the corvette ran out of depth charges and the sonar contact was lost. The boat had been badly damaged in the attack and was forced to return to base.

30 May 1941
The inbound boat, already heavily damaged after a previous depth charge attack and carrying 3 survivors from the Bismarck, was attacked by the British submarine HMS Sealion in the Bay of Biscay about 45 miles southwest of Belle-Ile. U-74 was unable to dive due to chlorine gas from the damaged batteries, but the alert deck watch managed to evade the spread of six torpedoes and the boat safely arrived at port.

1 May 1942
At 14.05 hours, the boat was attacked by the Hudson T9387 (233 Sqn RAF/B, pilot PO Vivian E. Camacho, RCAF) from Gibraltar with a stick of four 250lb depth charges about 30 miles east-southeast of Almeria, Spain. Two were seen to explode ahead of the swirl about 13 seconds after U-74 crash-dived and escaped without damage. (Sources: ADM 199/1782)

1 May 1942
At 22.22 hours, a U-boat was unsuccessfully attacked by HMS Unbroken with her last two torpedoes about 30 miles southeast of Almeria, Spain. HMS Georgetown, HMS Vidette and HMS Westcott on A/S patrol east of Gibraltar were subsequently sent to this position but found nothing. This must have been U-74 which was unaware of the torpedo attack and en route to assist the crippled U-573. (Sources: ADM 199/662)

2 May 1942

The sinking of U-74: At 07.40 hours on 2 May, U-74 was seen the last time by the Italian submarine Mocenigo (C.C. Paolo Monechi) which exchanged recognition signals with her in position 37°03N/00°15E. The U-boat sent a last radio message at 10.52 hours and was not heard of again. At this time, U-74 and U-375 were searching for U-573 which had been seriously damaged by an air attack the day before, but then managed to reach the Spanish port of Cartagena under own power around noon. At 14.12 hours, U-375 was bombed by the Catalina AJ162 (202 Sqn RAF/C, pilot FltLt R.Y. Powell) about 55 miles east of Cartagena and its sighting report brought HMS Wishart (D 67) (Cdr H.G. Scott, RN) and HMS Wrestler (D 35) (Lt R.W.B. Lacon, DSC, RN) to the scene. At 16.52 hours, HMS Wishart obtained a firm sonar contact in position 37°16N/00°01E and both destroyers carried out eight attacks until losing contact at 18.49 hours. HMS Wishart dropped 39 depth charges in four attacks while HMS Wrestler used its Hedgehog mortar twice and carried out two attacks with a full pattern of 14 depth charges each. Explosions were heard after both Hedgehog attacks and air bubbles were seen for about two minutes after the sixth attack. The destroyers continued to search the area until HMS Wishart had carried out two depth charge attacks on a firm contact located about seven miles from the original attacks at 22.30 hours. Shortly afterwards a large patch of thin oil was spotted to windward of the attacks. The last two attacks were carried out on U-375 which escaped undamaged, but the heavy depth charge attacks of the destroyers during the afternoon must have fatally damaged U-74 which sank with all hands about 50 miles east-southeast of Cartagena, Spain.

5 recorded attacks on this boat.