Any orders from the core fleet placed before noon will be delivered in the following morning, while orders placed after midday will be delivered before 5pm the next day.
Hewden is so confident it can deliver, it will give customers a £100 credit if it fails to meet the guarantee.
The hirer said it had analysed over 100,000 hire transactions to identify its 30 most popular plant and access product lines. This consists of excavators, telehandlers, dumpers, rollers, scissor lifts and telescopic booms.
Hewden CEO Kevin Parkes said: “I am very aware that, at times, we have been guilty of over promising and under delivering, and this needs to change.
“I am also very confident that we have the scale of assets, depots and delivery vehicles to meet the core fleet guarantee.
“We have invested heavily in these 30 product lines to ensure there are over 5,000 items covered by our core fleet guarantee throughout the UK.
Hewden ramped up its delivery capability after it invested in a new tracking system that gives full visibility of its asset base by the minute, and switched to a hub and spoke depot structure, giving nationwide coverage.
Looking ahead, the company plans to roll its Core Fleet concept out to other items of equipment.
Parkes added: “In the first month the guarantee went live we delivered 1,980 items of equipment from the Core Fleet and were late on only 15 occasions, a success rate of over 99%.”