The former Manchester United goalkeeper was an ever-present in League One for the Addicks last season.
Amos, who is out of contract, has been in talks with Nigel Adkins over a new deal.
However, it has been reported by the South London Press that the 31-year-old is interesting League One rivals Ipswich
That could open the door for MacGillivray, who last month was linked with a switch to The Valley.
The Scot claimed The News/Sports Mail’s Player of the Season in recognition of his excellent displays last season.
Boss Danny Cowley, though, opted not to activate a club option to retain the former Shrewsbury man for an addition 12 months.
That has rendered MacGillivray a free agent, with his contract expiring at the end of this month after three seasons at Fratton Park.
It certainly appears there will be major changes in the goalkeeping department for Charlton this summer, with goalkeeping coach Andy Marshall reportedly on his way.
Marshall is apparently heading to Championship side Birmingham, thereby reuniting him with ex-boss Lee Bowyer.
Should Amos also depart, they will leave Australian Ashley Maynard-Brewer as the main keeping option.
The 21-year-old made four appearances for the Addicks last season, although solely in cup competitions.
Pompey are still seeking a replacement for MacGillivray, although Alex Bass is pushing for the number one spot next season.
The Blues also released Duncan Turnbull and Taylor Seymour following their disappointing eighth-placed finish in League One.
In addition, goalkeeping coach John Keeley was not retained, with the long-serving member of Fratton Park’s staff later moving to Ipswich.
Cowley has previously admitting he is second to recruit two new keepers during the transfer window.
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