The road starts at M5junction 6, where it also links with the A449 and A4538. This first part of the road is non primary, as it parallels the M5. Several roundabouts along this section give access to the Worcester suburb of Warndon and the B4638. Beyond the B4638 junction the road becomes dual-carriageway, and at the next roundabout we start a multiplex with the A44 (with the A4440 number dominant) and gain its primary status. The A4440 turns left at the next roundabout to lose its multiplex with the A44. We now run along the original line of the A44 and that road actually reappears at the following roundabout, where we turn right, as a disembodied spur to M5J7.
Ambulances approaching Worcestershire Royal Hospital from the north do so via the A4538 and B4638 despite being longer. This is due to the fact the roundabouts on the A4440 add too much time to the ambulances' journey.
From this point the road was constructed as a single carriageway, with some three lane sections, despite it being very busy forming a Southern Bypass for Worcester. This has now been improved to dual carriageway as far as the River Severn. In 2019 work commenced to dual the section across the Severn, which involved the construction of a second bridge at Carrington.
The first roundabout is with unclassified roads to access Norton village and the St Peter's housing estate, followed by another roundabout for the A38. The River Severn is crossed immediately after the A38 junction; during periods of heavy rain the fields either side of the road can be flooded. Most of the flood water comes down the River Severn and River Teme from the catchment areas in Wales. Presently there are just two lanes across the bridge and the high embankment that is well above the flood plain. A parallel bridge is being constructed on the southern side to increase road capacity. The next roundabout is for the A449 to Malvern, followed by another roundabout for an unclassified road Rushwick. Our final roundabout (they like roundabouts on this road) is with the A4103 to Hereford and is where we rejoin the A44 which heads west into Wales.
The road was built in several sections during the late 1980s and early 1990s. The first section between the A449 and the A38 was classified as A422, despite not being connected to that road at the time.