Pratt, 24, began his career in Rochdale's youth system, and has a wealth of non-league football experience after playing for teams such as FC United, Clitheroe, Chorley, Colne, Chadderton and Padiham.
After a short loan spell at Mossley earlier in his career, he returned for a second spell at Seel Park in 2020.
He has scored seven goals in all competitions this season for the Lilywhites including a goal against his new club in a 2-1 victory over Hyde in the FA Trophy Third Qualifying Round.
Speaking on Hyde United's website, manager Nick Spooner said this about his new signing: "Harry is a player that I’ve been aware of in recent weeks.
"He has good technical ability and will bring us a more physical option in the final third."
Pratt will be in contention to face Gainsborough Trinity on Saturday.
Photo credits: Mossley AFC
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