Jacob Holland-Wilkinson Lewis Coulton, Joe Rodwell-Grant and Oliver Lombard will join the professional ranks when the first-team squad returns for training in July.
The quartet, all aged 18, have agreed one-year contracts with an option of a second year.
Strikers Holland-Wilkinson and Rodwell-Grant together with left-back Coulton all made the bench for the first-team during the season just finished.
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Holland-Wilkinson was an unused substitute seven times, Rodwell-Grant and Coulton both on the bench twice.
Goalkeeper Lombard was a regular in the Under-18s side.
Earlier in the season, Holland-Wilkinson had a loan spell with Lancaster City, while Rodwell-Grant had loan stays with Chorley and Bamber Bridge.
Last week, Holland-Wilkinson was named PNE's scholar of the year.
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