Allardyce, who replaced Avram Grant in June, expects Parker to line-up for his side in their Championship opener at home to Cardiff on Sunday.
However, the former Bolton boss admits the player will leave should the right offer come in and as such his plans for the new campaign do not include the 30-year-old.
"At the end of the day, Scott's position is delicate because at any one time, someone will hit the numbers that we would value him at," Allardyce told the Sun.
"If that's the case and it's the Premier League - a place where he wants to be - he will be gone. It would be wrong of me to plan with Scott."