The Blues defender is said to be keen on signing the left-back for a third time, as he gets stuck into a summer overhaul at Pompey.
Toffolo moved to the Terriers from Lincoln in 2020 and the 25-year-old made 31 appearances in the Championship last season.
The former Norwich man has a year remaining on his existing agreement and would command a fee, with Cowley also needing to convince the marauding talent to step down a division.
According to BBC Radio Solent’s, Andy Moon, it’s a deal the new Pompey head coach is looking to pursue, however.
Cowley has made it clear he needs to undertake major surgery on his Blues side this summer and a major overhaul is required.
The News revealed yesterday the 42-year-old is looking at bringing in as many as eight new faces this summer.
Pompey have been linked with Swindon midfielder Scott Twine and Cowley has indicated he’s keen on bringing Spurs midfielder Harvey White back to Fratton Park.
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