Portsmouth, who were relegated to League One last season, entered administration for the second time in three years in February 2012.
Ashley Brown, chairman of the Pompey Supporters' Trust, released the following statement on the club's official website: "This is an historic day for Portsmouth Football Club and for Pompey fans everywhere.
"At last, the tough work done over the last year is over and we can start to rebuild our club.
"Pompey fans are now days away from owning and running our club and becoming the biggest community-owned football club in the country.
"We have a lot of people to thank - and much more to say - but will do that once the detail of today's (April 10) settlement are finalised.
"For now, we would like to offer heartfelt thanks to Pompey fans all over the world who have pledged money and have saved our club from liquidation.
"Now the next chapter of hard work begins to transform our club into something the community of Portsmouth can be proud of - both on and off the field. Play up Pompey."
Trevor Birch, BDO partne and joint administrator of Portsmouth, said: "I am pleased to announce that we have reached an agreement with Portpin and the Pompey Supporters' Trust (PST) which paves the way for the PST to complete its purchase of Portsmouth Football Club.
"We were appointed to secure the best deal for creditors and today's developments enable us to fulfil that obligation.
"It is gratifying that both the PST and Portpin have worked hard to reach an agreement that safeguards the club's future without the need for a court decision. This is the best possible solution for everyone involved.
"We will now work with the PST, Portpin and the Football League to conclude the deal as quickly as possible in order to enable the new owners to begin the urgent task of rebuilding the club.
"The past year has been incredibly challenging for everybody involved with the club - fans, staff and players - and I want to thank them for their support.
"They deserve credit for keeping Portsmouth Football Club alive despite what, at times, seemed like insurmountable obstacles and I'm sure their actions will inspire supporters' groups at other clubs in the future."