While the actor - now a global star - has returned to his home town on numerous occasions in the past, he'll be honoured this time round with the Freedom of the Borough.
Liam is expected to make his arrival by limo, along with his proud mum, ahead of the official ceremony in the Council Chamber.
"This is a significant civic occasion, but we have been at pains to keep the formalities to a minimum - in keeping with Liam's relaxed style and recognising that this is, above all, a gathering of friends," Ballymena Mayor PJ McAvoy said.
"It will also be a real Ballymena-style celebration, with some of our fantastic local talent providing the music, Ballymena students providing their own cinematic tribute to Liam's life and work, and local produce providing guests with a literal 'taste of the region'."
We look forward to honouring an outstanding individual who has proved to be both an exceptional talent and a superb global ambassador for Ballymena.
Ballymena Mayor PJ McAvoy
Around 200 guests will attend the celebrations and Liam is expected to address the gathering, from the very stage on which he started his acting career as a member of the Slemish Players.
But will he be making the most of the 'freedom' his new accolade will afford him? Probably not.
"In years gone by, Freemen of the Borough earned tax benefits and could drive their sheep unimpeded through the town," Mr McAvoy explained.
"I'm afraid Liam won't reap those rewards on Monday, but he will certainly gain an insight into the esteem in which he is held in Ballymena."
The Freedom of Ballymena has previously been awarded to only three other people - Ian Paisley, Syd Millar and Sandy Spence.