The British squad had previously conducted a livery launch to demonstrate its revised paint scheme and new sponsor portfolio, continuing with a blue and black scheme into 2023.
This was painted onto last year's FW44, a car that managed eight points in the hands of Alex Albon, Nicholas Latifi and Nyck de Vries.
Ahead of its Silverstone run, the FW45 has been given its first public outing and features a number of notable differences over its predecessor as the Grove team hopes to haul itself off the bottom of the constructors' championship order.
This features a revised nose and front wing assembly, with the new nose design extending down to the first element and appears to be similar in form to the geometry used by the likes of Haas and AlphaTauri last season.
The team has also redeveloped its sidepod package, notably featuring an extended undercut below the cooling inlets while also featuring an upper channel at the aft section.
Thus it appears to be a mix of philosophies, borrowing design cues from both Red Bull and Ferrari as the Williams team strives for greater aerodynamic performance.
A more prominent tunnel appears at the rear of the engine cover around the tailpipe to allow for extra cooling at the back, also providing a distinct path for air to be corralled to the back of the car.
"It's philosophically an evolution," said head of vehicle performance Dave Robson at the earlier livery launch.
"Obviously the regulation changes around the floor dominate some of it, and then I think the other thing that you'll find that is most obvious is a bit of an update to the sidepod package, which is an evolution of what we did for the Silverstone upgrade package [in 2022].
"But we were a bit constrained then by the radiator layout and not wanting to completely change that. So, we've had an opportunity to work on that and lay things out a little bit differently. But they're probably the main visible things.
"But, philosophically, it's an evolution."
Williams was at its best in 2022 when it came to high-speed circuit layouts, which hindered its performance at circuits that required more downforce.
Robson added that this was an area of focus for the team, as it struggled to contend with circuits like Monaco and Hungary.
"The low-speed, high-downforce corners were certainly important to us in terms of how we spec the car out," he said.
"I think a lot of that is about its characteristics and how the drivers can utilise the downforce it does have. We've done a lot of work on that."
Returning driver Albon will shake the car down first, with rookie driver Logan Sargeant set to take up the reins later on.