The 18 year old midfielder, who made his Charlton debut when he was 16 and made 27 first team appearances so far this season for the League One side, was at Melwood yesterday for a medical.
Shelvey should agree terms today and will formally complete a £1.7m move at the end of May.
"Charlton have given Premier League side Liverpool permission to speak to 18-year-old midfielder Jonjo Shelvey about a transfer," confirmed a statement from the Addicks.
The deal looks likely to be the first of several both ways, with the two clubs in talks to arrange a strategic partnership.