Both organisations are coy on the likelihood of a four-year deal being extended, insisting decisions are some way off and would form part of ongoing dialogue anyway.
However, speaking to a number of senior Aon executives over the past three weeks, it has become clear the warm words with which United embraced only the fourth shirt sponsor in their history a couple of years ago are being backed up by action from a commercial department unmatched in the footballing world.
United's huge commercial army, so well represented on their present tour of the United States, are about to become the first club to post an annual turnover of £100million, excluding media and matchday revenues.
A fifth of that comes from Aon, the US-based risk management giant that, from 2010, agreed to pay £80million over four years to replace AIG as the name on United's shirts.
It has not taken long for the positive effects of being associated with arguably the world's most famous sporting institution to become clear.
"What we hoped for from the sponsorship is delivering - 100%," said Aon's chief marketing officer Phil Clement.
"In the same way as it was difficult for people in Los Angeles to understand Hollywood, so it must be hard for people who wake up and see Old Trafford just across the street to feel just what an incredible global phenomenon Manchester United is.
"If you go to Hong Kong, it is bigger than the Beatles. Traffic stops just because United are staying at a certain hotel.
"We have a 42-man executive team covering biggest business units around the world. In Korea or Mexico or Ecuador or Brazil, where soccer is so popular, each one of them said 'don't tell anyone but I am definitely getting the most out of this'."
But what does United do for Aon? How can a football club that employs 600 people and posted an annual turnover of less than £300million in October 2010 do so much for an organisation that employs one hundred times more staff and whose revenues are counted in the billions?
"We had some very ambitious goals for the company and its awareness and we were scouring the world looking at different ways we might be able to accomplish then because the brand was punching under its weight," explained Clement.
"We did not set out to do a sports marketing sponsorship but once we evaluated the opportunity with Manchester United, we found it was the best way to achieve our business objectives."
The rationale was simple. For a 'firm' whose spread was so vast, marketing, as with United's wider approach to a growing number of partnerships, had to be territory-specific.
What appeals to one part of Asia may have no impact in a different area, still less so in Africa, the Americas or Europe. It is cumbersome and expensive, with no guarantee of success.
"In half a century from now, when pictures of the day Manchester United became England's most successful team are published, our name will be on the shirt. It is the same with Wayne Rooney's bicycle kick against Manchester City," Clement continued.
"For the rest of their lives, kids who are aged between seven and 13 now will see Aon as a big, important company.
"The partnership has unified the firm. We have a common message and a common platform right around the world which creates a pretty strong bond between the firm and a prospective client."
Aon chief executive Greg Case added: "Sport has an unbelievably powerful voice. The interest in Manchester United is off the chart.
"But it is not just about doing business, you have to back it up with economic sustainability.
"We have a motto: Country, clients and colleagues.
"You have to service your clients but if you do not help your colleagues, your work in that country will not be sustainable.
"We have 60,000 colleagues. They have to be central for us. Manchester United has helped us reach out to them in a unified way."