21 May 1941
The boat was fired on by HMS Verbena astern of convoy HX 126 and forced to dive, and over the next four hours subjected to a barrage of some 125 depth charges from HMS Verbena and HMS Burnham until the corvette ran out of depth charges and the sonar contact was lost. Severe damage forced U-74 to return to base.

30 May 1941
Bay of Biscay, approx. 45 miles (72km) SW of Belle-Ile, inbound: U-74 was returning to base on the surface due to chlorine gas from severe damage from depth charging with three survivors from the Bismarck on board when she was attacked by British submarine HMS Sealion. Quick reaction by the deck watch allowed the boat to evade the spread of six torpedoes and make port without further damage.

1 May 1942
14.05 hrs, approx. 30 miles (48km) ESE of Almeria, Spain: Hudson T9387 (233 Sqn RAF/B, pilot PO Vivian E. Camacho, RCAF) on patrol from Gibraltar dropped four 250lb depth charges on U-74. Two were seen to explode ahead of the swirl about 13 seconds after U-74 dived. No damage. (Sources: ADM 199/1782)

1 May 1942
22.22 hrs, approx. 30 miles (48km) SE of Almeria, Spain: HMS Unbroken launched three torpedoes at a U-boat, without success. 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 en route to assist the crippled U-573. (Sources: ADM 199/662)

2 May 1942

The sinking of U-74: At 07.40 hrs on 2 May, U-74 was seen the for 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 hrs and was not heard of again. At this time, U-74 and U-375 were searching for U-573 which had been seriously damaged in an air attack the day before, but managed to reach the Spanish port of Cartagena under own power around noon. At 14.12 hrs U-375 was bombed by Catalina AJ162 (RAF Sqn 202/C, pilot Flt Lt R.Y. Powell) about 55 miles (89km) E 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 hrs 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 hrs. HMS Wishart dropped 39 depth charges in four attacks, while HMS Wrestler used her 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 at 22.30 hrs on a firm contact located about seven miles from the original attacks. Shortly afterwards a large patch of thin oil was spotted to windward of the attacks. The target of the last two attacks was U-375, which escaped undamaged, but the destroyer's heavy depth charge attacks during the afternoon must have fatally damaged U-74, which sank with all hands about 50 miles (80km) ESE of Cartagena, Spain.

5 recorded attacks on this boat.