The 21-year-old joins Alan Reynolds’ side having spent the 2019 season with Bohemians.
Dundee-born Allardice spent five years at Dundee United before moving to the League of Ireland in 2019.
The signing of Allardice adds to that of Sam Bone and Graham Cummins in the previous days as Alan Reynolds begins to shape his squad ahead of the 2020 campaign which begins away to St Patrick’s Athletic on February 14th.
Speaking to WaterfordFC.ie after signing, Allardice said:
“I spoke to Rennie a few weeks back. He set out his plan and targets for the season and I was delighted to be able to sign the contract.
“It’s nice when a gaffer has faith in you and he’s literally just told me to pick up where I left off last season. I want to play as much as I can, and I can’t wait to jump into pre-season in the coming weeks.
“The RSC is up there with one of the best around. The playing surface is fantastic and then you have a look at the facilities available and it’s a no-brainer.
“Waterford is a big club. So many players will say, when the fans are behind the team it’s a tough place to go.
“I had some good memories with Bohs, but I’m hoping for better ones this year in a blue shirt. Looking at the calibre of players Alan is bringing in, we’re going to have a strong side. I think we can all look forward to a good season. I’m here to be part of a winning side and I’m going to do everything I can do to make sure that happens.”
Speaking to WaterfordFC.ie after confirming the signing, manager Alan Reynolds said:
“It’s great to get Scott signed up for 2020. He did well last season in Bohs and played plenty of football so we think he’ll fit the bill.
“He’s a big, strong midfielder and he’s exactly the kind of player we’ll need this season.
“We’ve added Sam and Graham in the last few days too and there’ll be more to come soon.”