The last-minute decision to add the two schools leaves out two other Big East members, Boston College and Syracuse, that had gone through a formal process to get invitations.
ACC presidents are believed to have voted 7-2 in favor of asking Miami and Virginia Tech to join.
"We are very close to reaching a definitive conclusion to this process," ACC Commissioner John Swofford stated. "We expect to have an announcement in the near future."
The ACC had originally considered adding Miami, Boston College and Syracuse to allow it to split into two divisions and hold a football championship game, which would earn it more money.
Although National Collegiate Athletic Association rules require conferences have at least 12 members in order to hold a conference championship football game, an 11-school ACC could ask for that rule to be amended.
Several other scenarios were reportedly considered, including taking all four of the Big East members to form a 13-team ACC, but proponents couldn't get the seven votes necessary for passage.
Duke and North Carolina reportedly were opposed to almost all additions, while Virginia's administration was pressured by the state's government not to vote for anything that would leave Virginia Tech in a smaller and weaker Big East.
If Miami and Virginia Tech were to join the ACC, it would leave the Big East with just six schools that play Division I-A football, possibly costing it a berth in the lucrative Bowl Championship Series.
Virginia Tech is one of five Big East schools, joining Connecticut, Pittsburgh, Rutgers and West Virginia, that filed a lawsuit seeking 'hundreds of millions of dollars' in damages and an injunction to keep the ACC from expanding.
